research paper of millets

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• Published: 27 April 2018

Millets: a solution to agrarian and nutritional challenges

• Ashwani Kumar   ORCID: orcid.org/0000-0001-6315-5710 1 , 2 ,
• Vidisha Tomer 2 ,
• Amarjeet Kaur 1 ,
• Vikas Kumar 2 &
• Kritika Gupta 2  

Agriculture & Food Security volume  7 , Article number:  31 ( 2018 ) Cite this article

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World is facing agrarian as well as nutritional challenges. Agricultural lands with irrigation facilities have been exploited to maximum, and hence we need to focus on dry lands to further increase grain production. Owing to low fertility, utilization of dry lands to produce sufficient quality grains is a big challenge. Millets as climate change compliant crops score highly over other grains like wheat and rice in terms of marginal growing conditions and high nutritional value. These nutri-cereals abode vitamins, minerals, essential fatty acids, phyto-chemicals and antioxidants that can help to eradicate the plethora of nutritional deficiency diseases. Millets cultivation can keep dry lands productive and ensure future food and nutritional security.

Progress in scientific knowledge and technological innovations have led mankind into yet another stage of modern civilization. Application of novel research strategies into fundamental and translational research has brought an all-round development. In agriculture, strategized technological innovations, viz. development and selection of high yielding variety, use of synthetic fertilizers and pesticides, mechanization and irrigation facilities, have resulted in sufficient availability of food. Estimated global cereal production was 2605 million tons in 2016 and was forecasted to be 2597 million tons in 2017 [ 1 ]. Several short-sighted measures have enhanced productivity but have undermined sustainability and are eroding the very capacity of resource base leading to nutrient deficient saline soil and lowering water beds. In addition, changing climatic conditions have further hastened the vulnerability of farmers towards declining crop production. Dry lands constitute 40% of the global land surface and are home for about 1/3rd of the global population. These low fertile soils are predicted to elevate up to 50–56% in 2100 AD, and 78% of dry land expansion is expected to occur in developing countries [ 2 , 3 , 4 ]. According to the report of World Bank, hunger is a challenge for 815 million people worldwide [ 5 ]. The spate of farmer’s suicides in an agriculture-based country like India has reached to an average of 52 deaths/day, and reports of farmers selling their blood to earn a livelihood in drought-hit region of the country depict the severity of the agrarian crisis [ 6 ].

Sustainable crop substitutes are needed to meet the world hunger (cereal demand) and to improve income of farmers. Role of millets cannot be ignored for achieving sustainable means for nutritional security (Fig.  1 ). International crops research institute for the semi-arid tropics (ICRISAT) is focusing on increasing the productivity of millets and has included finger millet ( Eleucine corcana ) as sixth mandatory crop [ 3 , 4 ]. Millets abode vital nutrients and the protein content of millets grains are considered to be equal or superior in comparison to wheat ( Triticum aestivum ), rice ( Oryza sativa ), maize ( Zea mays ) and sorghum ( Sorghum bicolor ) grains [ 7 ]. The role of millets in designing the modern foods like multigrain and gluten-free cereal products is well known [ 8 ]. Due to the richness of millets in polyphenols and other biological active compounds, they are also considered to impart role in lowering rate of fat absorption, slow release of sugars (low glycaemic index) and thus reducing risk of heart disease, diabetes and high blood pressure. Due to increased awareness regarding the health promoting profile of millets, inclination towards their consumption has been observed. Present review envisages the agrarian requirements, nutritional information and health benefits imparted by these grains. Review also explores the millet-based products made traditionally along with the latest researches conducted worldwide.

Benefits of millets in a nutshell

Agrarian importance of millets

The demand of food will increase proportionately with growth in world population. At present about 50% of world's total calorie intake is derived directly from cereals [ 9 ]. Rice, wheat and maize have emerged as the major staple cereals with a lesser extent of sorghum and millets. Sharma [ 10 ] reported that an increase in the areas of crops with intense water requirements like rice, sugarcane ( Saccharum officinarum ) and cotton ( Gossypium ) has resulted in the increase in 0.009% in the distance between the ground level and ground water table and this loss is approximately equivalent to a loss of 7191 L of ground water per hectare. There is a lesser possibility of increasing the production of major staple cereals as the world is already facing the challenges of increase in dry lands and deepening of ground water level [ 3 , 10 ]. According to the report of the National Rainfed Area Authority (NRAA) even after realizing the full irrigation potential, about half of the net sown area will continue to remain rainfed [ 11 ]. This alarms the need of shifting to the alternative of current cereal staples.

Millets cultivation can be a solution to this problem as these can grow on shallow, low fertile soils with a pH of soil ranging from acidic 4.5 to basic soils with pH of 8.0 [ 12 ]. Millets can be a good alternative to wheat especially on acidic soils. Rice is very sensitive to saline soils and has poor growth and yield on a soil having salinity higher than 3dS/m [ 13 ]. On the other hand, millets like pearl millet ( Pennisetum glaucum ) and finger millet can grow up to a soil salinity of 11–12 dS/m. Millets have a low water requirement both in terms of the growing period and overall water requirement during growth. The rainfall requirement of certain millets like pearl millet and proso millet ( Panicum miliaceum ) is as low as 20 cm, which is several folds lower than the rice, which requires an average rainfall of 120–140 cm [ 13 ]. Most of the millets mature in 60–90 days after sowing which makes them a water saving crop. Barnyard millet ( Echinochloa frumentacea ) has the least maturation time of 45–70 days among millets, which is half to the rice maturation (120–140 days) time [ 14 ]. Millets fall under the group of C4 cereals. C4 cereals take more carbon dioxide from the atmosphere and convert it to oxygen, have high efficiency of water use, require low input and hence are more environment friendly. Thus, millets can help to phase out climatic uncertainties, reducing atmospheric carbon dioxide, and can contribute in mitigating the climate change. The major millets and their growing conditions in comparison to the staple cereals, i.e. rice and wheat, are tabulated in Table  1 .

Scientific interventions in terms of the use of molecular biomarkers, sequence information, creation of mapping populations and mutant have led to the development and release of high yielding varieties of millets throughout the world [ 22 , 29 ]. Newly developed hybrids are resistant to diseases and has increased per hectare production as compared to their parent varieties [ 29 , 30 ]. Millets have abundant natural diversity, and the release of new hybrids increases this variation by several folds. For example, pearl millet has approximately 140 species or subspecies belonging to the genus Pennisetum [ 31 ] and further maintenance of the gene bank accessions has increased this number to 65,400. The primary global collection of pearl millet is at ICRISAT with 33% of the world’s gene bank accessions. The largest gene accessions for finger millet, i.e. approximately 27% of the world’s total 35,400 accessions, are maintained by Bureau for Plant Genetic Resources, India. Chinese Institute of Crop Germplasm Resources (ICGR) maintains world’s 56% of the accessions of foxtail millet ( Setaria italica ), while National Institute of Agrobiological Sciences in Japan maintains the largest proso millet accessions collection with 33% of the world’s approximately 17,600 genebank accessions [ 32 ]. In addition to the improvement in varieties, the advancements in the post-harvest operations of millets have eased their processing. In past, due to the lack of suitable machinery, traditional methods like pounding, winnowing, etc., were used for the decortication of millet grains. These methods were labour intensive, and hence, the production of edible millets was limited [ 33 ]. Millet-specific threshers, decorticator, destoners and polishers have been designed by intervention of government agencies as well as private companies. These recent developments in post-harvest operations of millets have eased their processing and have paved way for utilization of millets in the development of food products. The cultivation of millets can provide an overall solution to the existing agrarian challenges and can prove a milestone in achieving United Nations commitment to end malnutrition in all its forms by 2030 [ 34 ].

Nutritional importance

World is in the clinch of several health disorders and chronical diseases. As per 2016 Global Nutrition report, 44% population of 129 countries (countries with available data) experience very serious levels of undernutrition, adult overweight and obesity [ 35 ]. A nutrient imbalanced diet is responsible for most of these diseases. According to the estimates of United Nations Food and Agriculture Organization, about 795 million people (10.9% of world population in 2015) were reported undernourished. While on the other hand more than 1.9 billion (39% of world’s population) adults ≥ 18 years of age were overweight and further 13% were reported to be obese [ 36 , 37 ]. The average body mass index (BMI) of the world’s population was reported to be 24 kg/m 2 in 2014 which is above the WHO standards for optimum health (21 to 23 kg/m 2 ) [ 38 ]. Obesity-related complications like cardiovascular diseases and diabetes have already been declared as epidemic by the world health organization. India is the home of world’s largest undernourished population. About 194.6 million people, i.e. 15.2% of total population of India, are undernourished. According to the 2017 Global Hunger Index report, India ranked 100th among 119 countries. The score of India is even poorer than Nepal, Sri Lanka and Bangladesh [ 39 ]. Protein energy malnutrition (PEM) was reported to result in 4,69,000 deaths with 84,000 deaths from the deficiency of other vital nutrients such as iron, iodine and vitamin A [ 40 ]. Obesity is also a major health concern in India with the prevalence rate of 11% in men and 15% in women. Status of malnutrition in world and India is presented in Table  2 . Millets secure sixth position in terms of world agricultural production of cereal grains and are still a staple food in many regions of world. These are rich source of many vital nutrients and hence, promise an additional advantage for combating nutrient deficiencies in the third world countries.

Macronutrients

Millets are nutritionally similar or superior to major cereal grains. The additional benefits of the millets like gluten-free proteins, high fibre content, low glycaemic index and richness in bioactive compounds made them a suitable health food [ 27 ]. The average carbohydrates content of millets varies from 56.88 to 72.97 g/100 g. Least carbohydrate content has been reported in barnyard millet [ 8 , 46 ]. The protein content of all the millets is comparable to each other with an average protein content of 10 to 11%, except finger millet, which has been reported to contain protein in the range of 4.76 to 11.70 g/100 g in different studies [ 47 , 48 , 49 ]. Finger millet protein is rich in essential amino acids like methionine, valine and lysine, and of the total amino acids present, 44.7% are essential amino acids [ 50 ]. This content is higher than the required 33.9% essential amino acids in FAO reference protein [ 51 ]. The mean value of protein reported from different studies depicts that proso millet has the highest protein content among millets (Table  3 ). The protein present in proso millet is comparable to wheat, but the amount of essential amino acids like leucine, isoleucine and thiamine is much higher in proso millet. The lipid content of millets as a group is comparable to that of wheat and rice (2.0% in wheat and 2.7% in rice) and ranges from 1.43 to 6 g/100 g. Among millets, the least lipid content has been reported in finger millet while the highest lipid content has been reported in pearl millet [ 46 , 49 , 52 ]. Millets are richest source of fibres, i.e. crude fibre as well as dietary fibre. Barnyard millet is the richest source of crude fibre with an average content of 12.8 g/100 g [ 8 ]. The highest dietary fibre content, i.e. 38% and 37%, has been reported to be in little millet ( Panicum sumatrense ) and kodo millet ( Paspalum scrobiculatum ), respectively. This content is 785% higher than rice and wheat; this make millets low glycaemic foods and hence a good choice for diabetic patients. In vitro studies of the soluble polysaccharides of finger millet (arabinose and xylose mainly) have proved them to be potent prebiotics and also possess wound dressing potential [ 53 , 54 ]. This resistant starch contributes towards dietary fibre, which acts as a prebiotic and hence enhances the health benefits of the millets [ 55 ]. Resistant starch also helps in the production of desirable metabolites such as short-chain fatty acids in the colon, especially butyrate, which helps to stabilize colonic cell proliferation as a preventive mechanism for colon cancer [ 56 ]. Table  3 gives the mean and standard deviation of the macronutrient content of millets as reported by various researchers.

Micronutrients

The minerals and vitamins are known as micronutrients as they are required in very small quantities. Minerals play an important role in the building of bones, clotting of blood, sending and receiving signals, keeping normal heart beat, cell energy production, transportation of oxygen, metabolize and synthesize fats and proteins, act as co-enzymes, provide immunity to the body and help nervous system work properly [ 60 ]. The mineral content in millets ranges from 1.7 to 4.3 g/100 g, which is several folds higher than the staple cereals like wheat (1.5%) and rice (0.6%). Calcium and iron deficiency is highly prevalent in India [ 61 ], and a large chunk of adult population is suffering from osteoporosis. Calcium content of finger millet is about eight times higher than wheat and being the richest source of calcium (348 mg/100 g) it has the ability to prevent osteoporosis. Barnyard millet and pearl millet are the rich source of iron, and their consumption can meet the iron requirement of pregnant women suffering from anaemia. The iron content of barnyard millet is 17.47 mg/100 g which is only 10 mg lower than the required daily value. Foxtail millet contains highest content of zinc (4.1 mg/100 g) among all millets and is also a good source of iron (2.7 mg/100 g) [ 57 ]. These nutrients, i.e. zinc and iron, play an important role in enhancing the immunity. Millets are also good source of β-carotene and B-vitamins especially riboflavin, niacin and folic acid. The thiamine and niacin content of millets is comparable to that of rice and wheat. The highest thiamine content in millets, i.e. 0.60 mg/100 g, is found in foxtail millet. Riboflavin content of the millets is several folds higher than the staple cereals, and barnyard millet (4.20 mg/100 g) has the highest content of riboflavin followed by foxtail millet (1.65 mg/100 g) and pearl millet (1.48 mg/100 g). The detail of micronutrient content of millets has been discussed in Table  4 . The incorporation of millets in the diet can help to eradicate nutritional deficiencies. Platel [ 62 ] has proposed for the use of millet flour as a vehicle for iron and zinc fortification in India.

Phenolic compounds

Phenolic compounds form a very large group of compounds containing the phenol functional group as a fundamental component. Conveniently, these may be classified into phenolic acids, flavonoids and tannins. Phenolic acids are further sub-classified as hydroxybenzoic acids, hydroxycinnamic acids, hydroxyphenylacetic acids and hydroxyphenylpropanoic acids. Chandrasekara and Shahidi [ 63 ] determined and characterized the free, hydrolyzed (esterified and etherified) and bound phenolic compounds in millets by HPLC–DAD-ESI-MS n . The highest amounts of hydroxybenzoic acid derivatives (62.2 μg/g) and flavonoids (1896 μg/g) were found in the soluble fraction of finger millet. Little millet (173 μg/g) and foxtail millet (171 μg/g) had the highest amount of hydroxycinnamic acid and their derivate in soluble form. The highest contribution to the total phenol content is in the form of the insoluble bound phenolics attached to the cell wall. Flavonoids are more prevalent in free form. Major phenols identified and quantified by different researchers are given in Table  5 . Millets phenols are reported to have antioxidant, anti-mutagenic, anti-oestrogenic, anti-inflammatory, antiviral effects and platelet aggregation inhibitory activity [ 64 ]. Total antioxidant capacity of finger, little, foxtail and proso millets is higher due to their high total carotenoid and tocopherol content which varied from 78 to 366 and 1.3 to 4.0 mg/100 g, respectively, in different millet varieties [ 65 ]. The beneficial effect of phenolics in diabetes is due to partial inhibition of amylase and α-glucosidase during enzymatic hydrolysis of complex carbohydrates and delays the absorption of glucose, which ultimately controls the postprandial blood glucose levels.

Other health benefits

Sireesha et al. [ 66 ] has demonstrated the anti-hyperglycaemic and anti-lipidemic activities of the aqueous extract of foxtail millet ( Setaria italica ) in streptozotocin-induced diabetic rats. In the study, they reported the dose of 300 mg of Setaria italica seed aqueous extract per kilo gram (kg) body weight produced a significant fall (70%) in blood glucose in diabetic rats after 6 h of administration of the extract. They also found lower levels of triglycerides, total LDL (low-density lipoproteins) and VLDL (very low-density lipoproteins) cholesterol and an increase in the levels of HDL (high-density lipoproteins) cholesterol in diabetic treated rats compared to those in diabetic untreated rats which demonstrates the hypolipidemic effect of aqueous extract. Choi et al. [ 67 ] studied the effect of dietary protein of Korean foxtail millet and found its importance in increasing insulin sensitivity and cholesterol metabolism. A remarkable reduction in insulin concentration of the rats fed with foxtail millet was demonstrated by this experiment. Lee et al. [ 68 ] investigated the effect of millet consumption on lipid levels and C-reactive protein concentration; it was found that hyperlipidemic rats fed with foxtail millet had decreased levels of triglycerides, which was in contrast to its previous researches [ 67 ]. Levels of C reactive protein, which is an indicator of inflammation, were also found to decrease in foxtail millet fed rats. Aqueous and ethanolic extracts of kodo millet have been reported to produce a dose-dependent fall in fasting blood glucose [ 69 ]. Further millets are gluten free and might have anti-carcinogenic properties [ 65 ]. The health benefits of millets in a nutshell are given in Table  6 .

Effects of processing on millets

Processing of millets decreases the anti-nutritional factors in millets and improves the bio-accessibility of nutrients. Many processing methods have been used traditionally like roasting/popping, soaking, germination and fermentation [ 80 ]. All these methods have been reported to have a significant impact on the nutritional value of the grain. Malting of millets improves access to nutrients and has been reported to increase the bio-accessibility of iron by 300% and of manganese by 17% [ 81 ]. The anti-nutritional factors decreased significantly with an increase in germination time due to hydrolytic activity of the enzyme phytase that increases during germination. The phytate content of millets can be reduced by germination as during the germination the hydrolysis of phytate phosphorus into inositol monophosphate takes place which contributes to the decrease in phytic acid. The tannins are also leached during soaking and germination of grains, and hence it results in the reduction in tannins [ 82 , 83 ]. Boiling and pressure cooking also result in reduction in tannins. Fermentation is known to reduce the anti-nutritional factors and hence improves the protein digestibility. Irradiation has also shown inhibitory effect against anti-nutrients, and it enhances the protein digestibility [ 84 ]. Extrusion cooking or high temperature short time (HTST) processing has been reported to reduce anti-nutrients like phytates, tannins and increase bioavailability of minerals [ 52 ].

Millet-based contemporary foods

Nutritional quality and drought-resistant properties of millets have drawn attention of various research agencies all over the world and have increased focus to improve the millet varieties and to enhance their use in processed food products. A schematic diagram for the preparation of composite foods from millets is shown in Fig.  2 . Some of the research work carried on the utilization of millet crops is discussed in this section.

Schematic diagram for developing millet-based composite foods

Shadang and Jaganathan [ 85 ] formulated the bakery products like biscuits, cakes and cookies using foxtail millet, finger millet, proso millet and pearl millet added with wheat flour. For biscuit and cake, the ratios of 10:90, 20:80 and 30:70 were selected, whereas for cookies, the flours were used in the ratios of 15:85, 20:80 and 25:75, respectively. The sensory evaluation of their products revealed that the combinations of all the three levels were well acceptable for the three products. Rai et al. [ 86 ] utilized alternate flours/meals based on rice ( Oryza sativa ), maize ( Zea mays ), sorghum ( Sorghum vulgare ) and pearl millet ( Pennisetum glaucum ) for the preparation of gluten-free cookies. Their study revealed that the combination of pearl millet and sorghum flour had the maximum sensory scores followed by the cookies prepared from rice and sorghum, maize and pearl millet, rice and pearl millet and control cookies. Best pasting properties were obtained from blends of maize and pearl millet followed by pearl millet and sorghum flour. However, maximum yield was obtained in control (wheat) cookies, i.e. 186.8%, while cookies prepared from rice and maize had the highest spread ratio. The cookies prepared from blend of pearl millet and sorghum was nutritionally rich and had higher fat, protein, ash and calorific values.

Surekha et al. [ 87 ] prepared the barnyard millet flour-based cookies with three different variations, viz. plain, pulse and vegetable. Their research findings indicated that among the three treatments, pulse cookies (90% barnyard millet flour + 10% soybean and green gram flour) had the highest (85%) overall acceptability followed by vegetable cookies (90% barnyard millet flour + 10% dehydrated carrots) with 80% overall acceptability with the least acceptability of 73.33% plain barnyard millet varieties. These cookies had a significant increase in macronutrient and micronutrient composition as compared to simple wheat flour-based cookies.

Ballolli et al. [ 88 ] prepared bread using varying concentrations of wheat flour and foxtail millet. It was found that wheat flour can be successfully replaced with foxtail millet flour up to 50% without significant effect on flavour and overall acceptability. However, the scores for colour, texture and appearance were reduced as compared to controlled sample. Addition of foxtail millet also resulted in a slight increase in the total protein and mineral content in comparison to the control bread.

Anju and Sarita [ 89 ] prepared biscuits using foxtail and barnyard millet. In the recipe, refined wheat flour was replaced to 45% with millet flour and all other ingredients like hydrogenated fat, eggs, baking powder and curd were same as the standard process for the biscuit making. The sensory evaluation of millet-based biscuits revealed a good overall acceptability and had a higher content of crude fibre, total ash and total dietary fibre as compared to refined wheat flour biscuits. Biscuits from foxtail millet flour had the lowest glycaemic index (GI) of 50.8 compared to 68 for biscuits from barnyard millet flour and refined wheat flour.

Pearl millet flour-based sweet, salty and cheese biscuits were prepared and reported by Sehgal and Kwatra [ 90 ]. Different blends containing pearl millet flour (40–80%), refined wheat flour (10–50%) and green gram flour (10%) were prepared. The sweet and salty biscuits prepared from refined wheat flour, blanched pearl millet and green gram were nutritionally sound as compared to biscuits prepared from wheat flour alone but had higher anti-nutrient (polyphenol and phytic acid) content.

Saha et al. [ 91 ] prepared biscuits from composite flour containing finger millet and wheat flour in the ratio of 60:40 and 70:30 ( w / w ). The hardness of biscuit dough was more in blend of 60:40 than 70:30 levels. An increase in adhesiveness and resistance of biscuit dough was found with the increasing levels of wheat flour. But the blend of 70:30 showed more breaking strength and expansion of biscuit after baking in comparison to blend of 60:40.

Snack foods

Dhumal et al. [ 92 ] developed potato and barnyard millet-based oil free, microwave puffed ready-to-eat fasting foods. Barnyard millet flour and potato mash, i.e. 50:50, 55:45 and 60:40, were prepared in three proportions and was steamed for 10, 15 and 20 min. Appropriate cold extrudates were obtained from mixture of barnyard millet flour and potato mash (55:45) after steaming the dough rolled in 50 mm thickness in kitchen pressure cooker (1 kg/cm 2 pressure) for 15 min. The cold extrudates prepared after steaming for 10 min were very white while that prepared after steaming for 20 min were brown in colour.

A Barnyard millet-based ready-to-eat snack food was prepared by Jaybhaye and Srivastav [ 80 ], in which barnyard millet, potato mash and tapioca powder was used in the proportion of 60:37:3. The dough was formed into thin rectangular-shaped, steam-cooked cold extrudate samples and was puffed with HTST puffing process at optimum temperature and time (238 °C/39.35 s). The puffed product had a moisture content of 9% and an expansion ratio of 2.05. After puffing, the product was oven-toasted at 116.26 °C for 20–23 min.

Multigrain flour

Kamaraddi and Shanthakumar [ 93 ] prepared multigrain flour by incorporating various millet flours. They concluded that the substitution of wheat flour with 10–20% of millet flour was possible. They optimized 10% substitution of finger, foxtail and little millet. The proso millet can be replaced to a level of 15% and barnyard millet up to 20%. The further increase in millet content resulted in a lower gluten content, sedimentation value, loaf volume of dough and decreased content of proteins in some flours as compared to wheat flour. The addition of millet also changed the colour of crumb from creamish white to dull brown. An increase in protein, ash and fat content was observed on addition of some millet flours.

Traditional millet-based products

Millets has been used for the purpose of food and feed from ancient times and has been a staple food particularly in diets of African and Asian people. These are consumed as flat bread, porridge, roasted and alcoholic and non-alcoholic beverages (Fig.  2 ). Millet porridge is a traditional food in Indian, Russian, German and Chinese cuisines. Millets are also used to replace commonly used cereals in local dishes like idli , puttu , adai, dosa, etc. Other traditional products like baddis, halwa, burfi, papad with added millet are also reported [ 68 , 94 , 95 ].

Non-alcoholic products

Appalu is made from a mixture of pearl millet flour and Bengal gram flour. Spices like sesame seeds, carom seeds, chilli powder and salt are added and kneaded into dough. Then, the dough is divided into small balls and flattened into round shape. These are then fried and served hot.

Samaipayasam

The word samai means little millet while payasam means kheer. For preparation of samaipayasam , roasted groundnuts, fennel and jaggery are ground into a fine powder separately. Little millet is added to boiling water by constantly stirring. After the flour is stirred in, jaggery solution is added and the mixture is cooked for a few minutes on low flame. This dish is served hot. This recipe is also made with other millets instead of little millet [ 96 ].

Korramurukulu

This crispy savoury Indian snack is prepared from a mixture of foxtail millet flour, Bengal gram flour. To this, small amount of spices like cumin seeds, chilli powder, sesame seeds and salt are added and formed into stiff dough with the help of water. The dough is placed in the hand extruder and murukus extruded are deep-fried until these turn brown [ 97 ].

Alcoholic beverages

It is a finger millet-based ( Eleucine coracana ) fermented beverage mostly prepared in the Lug valley of Kullu; Bhangal, Luharti of Kangra district, Balh valley, Barot valley of district Mandi and regions of Sirmour, Himachal Pradesh, India [ 98 , 99 ]. A mixture (inocula) of roasted barley and local herbs known as ‘ dhaeli ’ is used to carry out fermentation. The millet flour is kneaded with water to make dough and left in a container for 7–8 days for natural fermentation. The fermented flour is half baked into rotis , cut to pieces and cooled. Then, the roti pieces and powdered dhaeli with sufficient amount of water and jaggery are put into smoke-treated earthen pots and allowed to ferment for 10 days by covering the pot. After the completion of fermentation, liquid is filtered and stored in specially designed earthen pots, sealed air tight from the top. The product has been reported to have 5–10% of alcohol [ 99 ].

Madua is among the most popular finger-millet-based beverage prepared in Arunachal Pradesh. The millet is roasted for 30 min followed by cooling and cooking until soft. The softened grains are mixed with starter culture and allowed to ferment in a perforated basket covered with Ekam leaves for 4–7 days. After completion of fermentation, hot water is poured from top and collected in a container. The collected liquid is known as madua . A good quality madua is golden yellow in colour, sweet in taste and has good alcoholic flavour. Themsing , rakshi , mingri and lohpani are other finger millet-based alcoholic beverages produced and consumed in Arunachal Pradesh, India [ 100 ].

Oshikundu is a traditional cereal-based sour–sweet beverage of Namibia. It exits in both alcoholic and non-alcoholic form. It is brewed from pearl millet ( Pennisetum glaucum ) meal locally known as mahangu , malted sorghum ( Sorghum bicolor ), bran and water. Brewing of oshikundu is a household practice by rural women for their daily household consumption and for sale in the open markets in some towns of northern Namibia. The production process involves the addition of boiled water to mahangu meal, and the mixture is left to cool to room temperature with occasional stirring. Malted sorghum meal and bran are then added to the mixture. The step of bran addition is optional depending on the availability and preference of using bran in brewing. After the preparation of mixture, some amount of previously fermented oshikundu is added. The final mixture is then diluted with water depending on the amount of starting material used and desired volume of the final product. The mixture is then left to ferment at room temperature for an average one and half hour after which oshikundu is ready to drink. The alcohol is produced by the yeast fermentation of malt sorghum. It is a perishable beverage with a shelf life of less than 6 hours and is drunk on the same day [ 101 ].

Koozh is another fermented beverage made with millet flour and rice and consumed mainly by ethnic communities in Tamil Nadu, India [ 102 ]. It is mainly prepared using finger millet ( Eleucine corcana ); however, use of pearl millet has been reported in other places. The preparatory steps of koozh involve two fermentation stages. The process starts with grinding of the millet to flour, mixing with subsequent water to make slurry and left this to ferment overnight. On the second day, broken rice (20% by weight of millet) is cooked in excess water, into which the overnight fermented millet slurry is mixed and cooked to make a thick porridge called noyee . The fermentation of this porridge for 24 h results in kali , a semi-solid porridge to which the required amount of potable water was added (1:6 w/v) and hand-mixed with salt to prepare koozh.

Acceptability of millet-based products

The effect of addition of millets on the sensory acceptability of food products is scanty. Some researchers have reported the increased acceptability of the products on addition of millets, and literature on the decreased acceptability is also available. Florence et al. [ 103 ] reported high sensory acceptability in pearl millet-based cookies. Okpala et al. [ 104 ] reported a sensory acceptability of 7.1 on a scale of 9.0 points for 100% sorghum-based cookies. The acceptability was increased to 7.2 when a blend of cocoyam flour, fermented sorghum flour and germinated pigeon pea flour was used in the ratio of 66.6:16.7:16.7, respectively. In a study based on extruded products prepared from sorghum flour, corn flour, whey protein isolate and defatted soy flour, decreased acceptability was reported with increased content of sorghum [ 105 ]. The use of millets as a blend with other cereals, pulses or legume has been reported to have an increase in overall acceptability of the product [ 104 , 105 , 106 ]. In addition to sensory aspects, the presence of anti-nutritional factors like phytic acid, tannins and phenols limits the use of millets as food [ 105 ]. High content of phytic acid was reported in the biscuits prepared using pearl millet [ 104 ]. Similar results have been reported by Mbithi-Mwikya et al. [ 50 ] in composite mix developed from unprocessed finger millet, kidney beans, peanuts and mango puree. The products were reported to be unfit for the infant consumption due to the presence of phytic acid, trypsin inhibitor and tannins content. However, the processing methods like roasting, malting, germination and soaking have been reported to reduce the anti-nutritional content [ 82 , 105 ].

Conclusions

Millets can easily thrive in extreme conditions like drought, and some wild varieties can even prevail in flooded areas and swampy grounds. These have low glycaemic index, abode gluten-free protein and are rich in minerals (calcium, iron, copper, magnesium, etc.), B-vitamins and antioxidants. These extraordinary traits make them nutritious and climate change compliant crops. These can not only serve as an income crop for farmers but also improve the health of the community as a whole. Existing limitations, i.e. the presence of anti-nutritional factors and low sensory acceptability of millet-based products, can be overcome by the scientific interventions. The anti-nutritional factors can be inactivated by processing methods like cooking, roasting, germination and fermentation. The sensory acceptability of millet-based products can be enhanced by mixing millet flours with other flours of high acceptability and preparing composite foods. The use of millets in commercial/packaged food will encourage farmers to grow millets and will open new opportunities and revitalize the farmers. The inclusion of millet-based foods in international, national and state-level feeding programs will help to overcome the existing nutrient deficiencies of protein, calcium and iron in developing countries.

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Kumar, A., Tomer, V., Kaur, A. et al. Millets: a solution to agrarian and nutritional challenges. Agric & Food Secur 7 , 31 (2018). https://doi.org/10.1186/s40066-018-0183-3

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Nutritional and functional roles of millets-A review

Affiliations.

• 1 Environment-Omics-Disease Research Center, China Medical University Hospital, China Medical University, Taichung, Taiwan.
• 2 Graduate Institute of Clinical Medical Sciences, China Medical University, Taichung, Taiwan.
• 3 Faculty of Science, Department of Health Sciences, University of Mauritius, Réduit, Mauritius.
• 4 Science Faculty, Department of Biology, Selcuk University, Konya, Turkey.
• 5 Department of Environmental Sciences, Bharathiar University, Coimbatore, India.
• PMID: 31353706
• DOI: 10.1111/jfbc.12859

The available cultivable plant-based food resources in developing tropical countries are inadequate to supply proteins for both human and animals. Such limition of available plant food sources are due to shrinking of agricultural land, rapid urbanization, climate change, and tough competition between food and feed industries for existing food and feed crops. However, the cheapest food materials are those that are derived from plant sources which although they occur in abundance in nature, are still underutilized. At this juncture, identification, evaluation, and introduction of underexploited millet crops, including crops of tribal utility which are generally rich in protein is one of the long-term viable solutions for a sustainable supply of food and feed materials. In view of the above, the present review endeavors to highlight the nutritional and functional potential of underexploited millet crops. PRACTICAL APPLICATIONS: Millets are an important food crop at a global level with a significant economic impact on developing countries. Millets have advantageous characteristics as they are drought and pest-resistance grains. Millets are considered as high-energy yielding nourishing foods which help in addressing malnutrition. Millet-based foods are considered as potential prebiotic and probiotics with prospective health benefits. Grains of these millet species are widely consumed as a source of traditional medicines and important food to preserve health.

Keywords: millets; nutraceuticals; pharmacological activity; staple food; underutilized crops.

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Original research article, assessing millets and sorghum consumption behavior in urban india: a large-scale survey.

• 1 Smart Food Initiative, International Crops Research Institute for the Semi-Arid Tropics, Hyderabad, India
• 2 Organization for Advanced and Integrated Research, Kobe University, Kobe, Japan
• 3 Development Strategy and Governance Division, International Food Policy Research Institute, Lilongwe, Malawi
• 4 United Nations International Children's Emergency Fund, Lilongwe, Malawi
• 5 Marketing Leadership Institute, SR Global Media and Research Pvt. Ltd, Hyderabad, India
• 6 Thought Folks Digital, Hyderabad, India
• 7 Innovation Systems for the Dry Land, International Crops Research Institute for the Semi-Arid Tropics, Hyderabad, India

There is growing attention by governments and industry in regard to the role played by millets (including sorghum) to help build resilience for farmers and cope with climate change, malnutrition, diabetes, and some other major issues. To understand public knowledge and practices of consuming millets in urban areas, a survey was conducted with 15,522 individuals from seven major cities of India using a structured questionnaire, and after data cleaning 15,139 observations were subjected to analysis using descriptive and inferential statistics. It was found that the largest group among early adopters of millets were people with health problems (28%), it being the single largest reason for consuming millets, followed by those wanting to lose weight (15%) and those selecting millets for its taste (14%). There was a significant gap between people who were health conscious (91%) and those who were sure millets were healthy (40%). The major reason the respondents did not eat more millets was that it was not eaten at home (40%), followed by reactions such as not liking the taste (22%). Reaching the urban consumers through social media is recommended, given that it is their main source of information. There was no statistically significant relationship between state-wise per capita production and frequency of consumption of millets in the urban areas ( p = 0.236). In conclusion, three key actions are recommended to enhance the consumption of millets: developing delicious products to satisfy the taste, providing knowledge on nutritional and health facts on millets, and improving accessibility of millets in urban markets.

Introduction

The recent paper from The Lancet Commissions ( Willett et al., 2021 ) recognizes the need for identifying healthy and environmentally sustainable diets and enhanced usage of underused plant species, such as quinoa, millets, sorghum, or teff grains, due to their climate resilience and dense nutritional content. It also clearly captured that among 14,000 edible plants, only three crops, namely, rice, maize, and wheat, contribute 60% of caloric intake. On the other hand, the SDGs 2030 have its ambitious goal of eliminating all forms of malnutrition by 2030. To achieve this, interventions are required to replace the major portion of the diet currently occupied by rice, wheat, and maize with highly nutritious grains, such as millets.

In India and other Asian and African countries, millets commonly include sorghum, pearl millet, and a range of small millets ( Vetriventhan et al., 2020 ). The term “millets” in this paper refers to all of these crops. India is the leading producer and consumer of different types of millets, such as finger millet, pearl millet, kodo millet, foxtail millet, barnyard millet, proso millet, and little millet ( www.smartfood.org 1 , 2 ). India is the sixth largest producer of sorghum globally ( www.smartfood.org ). Traditionally, many kinds of foods and beverages were made from these grains in different regions, which played an important role as a staple food in the local food culture. However, their presence in the Indian food basket has been declining over the years largely due to government policies favoring the production and consumption of fine cereals, such as rice and wheat ( Kane-Potaka and Kumar, 2019 ), as well as rising incomes and urbanization. Between 1960 and 2015 in India, wheat production more than trebled, and rice production increased by ~800%; on the contrary, millet production was stagnant at low levels ( Kane-Potaka and Kumar, 2019 ). Between 1962 and 2010, India's per capita consumption of millets fell drastically from 32.9 to 4.2 kg, while that of wheat almost doubled from 27 to 52 kg ( www.indiaspend.com ) 3 . Another study reported in particular on pearl millet that per capita consumption trend declined between 1972/1973 and 2004/2005 in both rural and urban regions of India from 11.4 to 4.7 and from 4.1 to 1.4 kg per year, respectively ( Basavaraj et al., 2010 ). A similar declining trend in per capita consumption was reported for sorghum in both rural and urban India from 19.1 to 5.2 and from 8.5 to 2.7 kg per year, respectively, representing 68 and 70% reduction ( Parthasarathy Rao et al., 2010 ).

Millets are often referred to as smart food ( www.smartfood.org ), which is “good for the individual” (nutritious and healthy), “good for the planet” (environmentally sustainable), and “good for the farmer” (resilient). Millets are recognized for their resilience, ability to survive under high temperatures and in degraded soils, and minimum requirements of water, pesticides, and fertilizers ( Saleh et al., 2013 ). Their farming methods leave a lower carbon footprint than the major staples that are grown with greater use of fertilizers and pesticides. Millets complement commonly used legumes in India, such as pigeon pea and chickpea, for amino acid content to form complete protein with improved digestibility upon cooking ( Anitha et al., 2019a ). Apart from protein, depending on the variety and species, millets are also rich in minerals, such as iron, zinc, and calcium, which deliver health benefits to all age groups and genders.

The high nutritional content of millets compares well with other foods with similar nutritional value; it is especially high compared with polished rice, maize, and refined wheat flour, the post-green revolution major staples ( Longvah et al., 2017 ). Innovative millet processing technologies that provide safe, easy-to-handle, ready-to-cook, and ready-to-eat products and meals at a commercial scale are mainly available in urban areas ( Ushakumari et al., 2004 ), where rice and refined wheat flour dominate and are much more accessible and affordable. The consumption of refined grains, namely, refined white rice, is shown to be associated with non-communicable diseases, such as type II diabetes mellitus ( Radhika et al., 2009 ) and obesity. This has led to an increasing emphasis globally on consuming whole grains ( Edge et al., 2005 ), underlining the importance of mainstreaming nutritious smart food crops and promoting them as a staple. This is one of the major objectives of the Smart Food initiative ( Singh and Raghuvanshi, 2012 ; Kane-Potaka, 2018 ). Providing more nutritious and healthier traditional whole grain and multigrain substitutes for refined carbohydrates can be an important aspect of therapeutic dietary modification and diversity.

There is a growing interest in reviving millets in India ( Kane-Potaka and Kumar, 2019 ) and also globally, owing to their nutrition content and ability to grow in harsh climatic conditions due to their climate smart traits. The Government of India declared 2018 as a National Year of Millets and followed on with preparing a national Millet Mission, as well as a proposition to the Food and Agricultural Organization of the United Nations (UN) for a UN International Year of Millets. Several state governments in India also followed suit to establish state millet missions. These initiatives all recognized the need and built-in components to engage with consumers to drive demand and not only to invest in agricultural production and productivity. The demand for value added (processed) millet-based food products (being promoted as health foods) is increasing steadily in global markets ( Rooney, 2010 ). This transition phase during which perceptions of millets are changing and there is greater health consciousness ( Umanath et al., 2018 ) is the right stage to assess current knowledge, perceptions, and practices related to millets, which will lay the foundation for a plan to promote millets as a staple effectively.

Understanding current knowledge and practices is important for researchers, nutrition volunteers, community health workers, and food manufacturers in planning millet-based products, interventions, and promotional activities to improve the nutritional status and general health of the population and for companies to make nutritious foods a viable business. A limited number of studies have investigated the perceptions, awareness, and knowledge on millets. For instance, the study conducted on pearl millet, finger millet, and sorghum in Maharashtra state involved a relatively small sample of 111 participants who were all diabetic ( Nambiar and Patwardhan, 2014 ). Another study on finger millet and oats in South India recognized the widespread lack of knowledge about the nutritional benefits of finger millet and the need to promote it through a survey with 260 women ( Sreedhar and Shaji, 2017 ). To our knowledge, no formal study has focused on understanding consumers' knowledge, perceptions, and attitude on millets using a large sample survey covering various states of India. Therefore, this study aimed to assess the knowledge, perceptions, and practices of millets consumption in seven major cities of India.

A large sample survey was conducted to collect primary data on trends, attitudes, and opinions on millets consumption behavior of the target population who were urban consumers in India. The data were statistically analyzed to examine the relationship between variables ( Creswell and Creswell, 2017 ). Surveys on beliefs, reasons, and barriers in purchase and consumption are widely used to evaluate food choice behavior ( Roche et al., 2012 ; Irianto, 2015 ).

Survey Participants

Convenience sampling ( Jager et al., 2017 ) was adopted where respondents were approached in shopping malls. This provided access to large numbers of men and women in cities in a short time at locations they commonly frequent for purchasing groceries. It also accessed shopping areas where targeted individuals purchased food ingredients for use at home. Participation in the survey was voluntary and anonymous. Participants were informed upfront of the purpose of the study and the use of the data, emphasizing that the information requested would be exclusively used for statistical analysis, guaranteeing confidentiality. Informed consent was obtained before the interview. To ensure confidentiality, the collected data were managed anonymously by providing sample identity based on institutional data management policy.

The optimal size of the survey sample was identified considering both the budget and the statistical power. As a result, a total of 15,522 individuals from seven cities in seven states of South, West, North, and East India participated in the survey. Approximately 300 survey personnel were deployed to conduct the interviews. The participants were provided with an information flyer and a link to an App about millets at the end of the survey.

Questionnaire

A structured questionnaire was developed with questions about millets including Food Frequency Questions (FFQ) on millet by custom designing to understand the millet consumption patterns [Usual Dietary Intakes: NHANES Food Frequency Questionnaire (FFQ) | EGRP/DCCPS/NCI/NIH (cancer.gov)], followed by socioeconomic information of the respondents ( Supplementary Materials ). An expert panel was consulted to ensure the validity and clarity of the questions. To ensure reliable results, the questionnaire was pre-tested with 20 subjects before the survey to validate and identify problems with the content and comprehensiveness of the questions, as well as other causes of (dis)satisfaction, which were added to the options sheet used by the interviewers. Based on the satisfaction or dissatisfaction, annotations, and comments from the pre-testing, the questionnaire was improved and finalized, which helped ensure that the questions were understood by both interviewers and respondents and minimize subsequent measurement errors.

The survey was administered to visitors to shopping malls over the course of August 2017. Participants were asked the questions in person about their knowledge, perceptions, and consumption patterns, as well as the reasons for their practices and sources of information, on millets.

All the qualitative and quantitative questions were asked without prompts or options to select. The interviewees had options on the question sheet to assist with faster recording, and additional answers were written. These options were collated from pilot testing of the questions, and the options for demographics were based on common standards. A picture of three popular smart food grains, namely, finger millet, pearl millet, and sorghum, was used as a visual aid at the beginning of the survey along with a structured questionnaire. The picture included the crop and the grain with their names in English, Hindi, and the state language. The income of a participant's household was self-reported and included a variety of questions designed based on standard methods for grouping participants in poor, middle, and rich income groups ( Dalvi et al., 2020 ).

Data Analysis

Data were cleaned, organized, coded, and subjected to statistical analysis using STATA version 16 ( StataCorp, 2019 ). After data cleaning, 15,139 observations were subjected to analysis ( Table 1 ). However, the tables of results may include a smaller number of observations depending on the number of missing observations in the variables included in the specific analysis. Descriptive statistics, such as frequency, mean, median, and standard deviation, were used to present the knowledge and practices among participants. Inferential statistical tools, such as tetrachoric correlation, Z-statistics, and ordered probit regression ( Daykin and Moffatt, 2010 ), were performed to examine the influence of various factors on consumption habits and perceptions toward millets. The dataset is currently stored in Dataverse and managed by ICRISAT ( https://doi.org/10.21421/D2/JUMRM8 ).

Table 1 . Demographic information on the sampled respondents.

Among the respondents, 9,453 were women and 5,686 were men, and their average age was 41.2 years. Overall, a higher proportion of women were interviewed as they constituted the majority of grocery shoppers in the town ( Table 1 ). In particular, women constituted an even higher proportion of grocery shoppers in Ahmedabad and Delhi.

Recognition of Millets

Although not presented in the table, 89% of the participants reported that they knew millets. Among the participants who responded “yes” to consuming millets, most of them did not recognize it when shown the picture of sorghum, pearl millet, and finger millet ( Supplementary Figure 1 ). An example response from a 28-year-old female was “I have been drinking ragi malt (a milk drink made from finger millet) almost every day for the past 3 years since my first pregnancy, but I had no idea what ragi (finger millet) looked like, and today, I see it in the picture that you showed to me, and this is fabulous, and thanks to smart food for all the good work.”

Although not shown in the table, among the three crops, sorghum had the highest recognition rate (59.3%) when shown images of the crop and the grain, followed by finger millet (54.8%). There was no difference in recognition of millets between age groups, though these crops were a traditional staple. To our surprise, the youngest group, below 20 years, had similar or higher recognition of the crops, especially pearl and finger millets, than other age groups.

Recognition of all the three crops among both women and men was the highest in Mumbai, followed by Bengaluru, the lowest being in Kolkata ( Table 2 ).

Table 2 . Recognition of millets and sorghum in each city (% of respondents).

Awareness of Nutritional Value

It was identified that the awareness of millets was prevalent in the last 4 years, and that more than 23% of the respondents mentioned they had heard about or started eating millets <5 years before.

When asked whether they thought millets were healthy, less than a half (40%) of the respondents were sure that millets were healthy ( Table 3 ). On being asked what they thought was healthy about millets, the answers included: it is good for the general health of women (22%), is high in iron (20%), is high in calcium (15.5%), and is good for diabetes (12.5%). The rest of the participants (30%) thought that it was good for bone health, cancer, during pregnancy, and for babies ( Table 3 ). Most (91%) of the respondents said that they were reasonably or highly health conscious (56.6 or 34.4%, respectively; Table 3 ).

Table 3 . Health consciousness of the participants.

Sources of Information

When asked what their source of information on health and foods was, by far the most influential was social sources, the largest being social media with 50.7% of the participants opting for it, while TV shows were the sources for 38.7%, and family and friends were the sources for 36.9%. The other influential information sources were courses (33.9%), newspapers (15.3%), and books (14.8%; Figure 1 ).

Figure 1 . Participants sources of information on millets and sorghum.

Consumption

Although there was a considerable proportion of consumers eating millets frequently (49.6% consumed 1 or more times per week), there was also a reasonable proportion of people who had never or almost never consumed millets (34.9% consumed millets never or up to two times a year; Figure 2 ). The city-wise frequency of consumption of millets was linked to the recognition of these crops in each city, as shown in Table 3 . Bengaluru led in terms of consumption, while Ahmedabad and Delhi had the lowest consumption frequencies. In Bengaluru, no respondent mentioned that they never/rarely consumed millets. In fact, it was the only city where all the respondents consumed these crops at least once a month. Approximately 71.2% of the respondents in Bengaluru consumed millets at least once a week. This was followed by 57.6 and 56.1% of the respondents being frequent consumers and 26.8 and 25% never/rarely consuming millets in Chennai and Hyderabad, respectively. Mumbai and Kolkata ranked next with 52.9 and 52.3% being frequent consumers and 29.6 and 29.6% never/rarely consuming. Delhi and Ahmedabad had the lowest frequency of consumption with 41.9 and 37.7% consuming frequently and 47.1 and 55.5% never/rarely consuming millets, respectively ( Figure 2 ). This indicates that South India is a much greater consumer of millets.

Figure 2 . Frequency of consumption of millets and sorghum by participants from seven cities.

How Millets Are Eaten

The most common form in which millets were eaten at the pan India level was as ready-to-eat food, as reported by 45.6% of the respondents. Breakfast porridge, which is one of the traditional forms of consumption, stood at the top at 38.3%. Ahmedabad and Bengaluru had the largest consumption of ready-to-eat food, with up to 65.7 and 63.4% of the respondents saying that this was the most common form in which they consumed millets ( Figure 3 ).

Figure 3 . Common forms in which millets are eaten by participants of the survey in different cities of India.

Reasons for Consumption

Figure 4 presents the reasons stated for the consumption of millets. The major reason at the pan India level was the prevalence of health problems including but not limited to diabetes, heart conditions, bone health, and general health. The proportion was especially large in Ahmedabad (48.1%) and Delhi (42.5%). The only two cities where this was not the number one reason were Chennai and Hyderabad, where taste preference was the major reason for eating millets. The second major reasons for eating millets pan India were for weight loss (15.1%) and its taste (14.6%).

Figure 4 . Respondents reasons for consuming millets and sorghum in each city.

However, the reason for eating it based on taste preference was not consistent across cities and ranged widely (7–21%); it was predominant in Ahmedabad and Delhi that had lower frequency of consumption. Health and fitness were together chosen as the major reasons for eating millets by at least 58.0% of the respondents. However, few said that they ate it just because it was healthy (7.7%); this trend was consistent across all the cities, ranging from 5.1 to 12.6%. This indicates that a specific health problem is an influential driver for people to eat millets, rather than just because millets are healthy. More women tended to attribute their consumption of millets to health issues and weight loss ( Table 4 ), while men tended to consume it simply because it was served at home. Furthermore, low income respondents tended to consume millets for the taste and subsistence and not to lose weight; neither did they find millets cheap.

Table 4 . Relationship between reasons for consuming millets and sorghum and the demographic profile of the respondents: tetrachoric correlation coefficients and p -values ( n = 15,513).

The most prevalent health reasons for eating millets included weight loss (the top ranked reason especially a primary reason by women 30–50 years old); diabetes (many diabetic patients said that their doctor had recommended eating millets); blood pressure; cancer; skin diseases (this was noted particularly from Bangalore and Mumbai participants who believed that sorghum and finger millet were good for skin and hair growth, and some doctors who participated in the survey said that they ate finger millet a few times a week for better skin); eye sight problem; stronger bones; and healthy pregnancy and baby growth.

Reason for Not Consuming More

The survey further enquired why people did not consume (more) millets. Overall, the family eating custom at home was the most frequently stated reason by nearly 40% of the respondents. Only Kolkata and Chennai differed in this trend, both citing limited availability as the key reason and its high price as another. It is worth noting that only 3% of the respondents in Bengaluru cited limited availability of millets as a concern, as the state is the largest producer of millets in India. Kolkata and Chennai had smaller production of millets. Chennai was also the place where respondents had the lowest awareness of all three millets. In Bengaluru, the major reasons cited for not eating (more) millets were their taste and family dietary customs. Pan India, the second major reason for not consuming more millets was the taste, cited by 22% of the respondents. Cooking time of millets was of significance in all the cities ( Figure 5 ).

Figure 5 . Stated reasons for respondents not consuming more millets/sorghum.

Table 5 shows the tetrachoric correlation between the reasons stated for infrequent consumption of millets and the demographic profile of the respondents. Unexpectedly, women who did not frequently consume millets tended to attribute it to a dislike of the taste and family custom, while men attributed it to the limited availability, high price, and long cooking time. Both low and high income groups showed similar tendencies, whereas the middle income group exhibited a distinct set of dispositions. The latter group, when not consuming millets frequently, attributed it to unfavorable taste and family custom. Table 6 shows the Spearman's non-parametric correlation between the frequency of consumption and the reasons stated for not increasing the frequency. Those who consumed less frequently were more likely to mention family custom as the reason. In contrast, those who consumed more frequently tended to mention taste, high price, non-availability in markets, and long cooking time as reasons for not increasing the frequency of consumption.

Table 5 . Tetrachoric correlation between respondents' reasons for not consuming millets/sorghum and their demographic profile.

Table 6 . Spearman's coefficient of correlation between frequency of consumption and their reason for not consuming more millets and sorghum ( n = 13,840).

Production and Consumption

Table 7 shows the state-level production of millets, as well as their levels of consumption, in the cities studied. Karnataka was the largest producer of these crops, followed by Maharashtra, Gujarat, and Tamil Nadu, confirming the concentration of production in southern states of India. Except in Gujarat, urban consumers in Karnataka and Maharashtra consumed these crops at relatively high frequency, with “once or twice a week” being the median. Despite Gujarat being the largest producer of pearl millet, it exhibited the smallest consumption, clearly showing that its large production had little impact on urban consumption. On the other hand, consumers in Delhi consumed these crops moderately (once a month), but their production was small. In contrast to these cities, Telangana and West Bengal consumed millets frequently despite less production.

Table 7 . Production (tons) of millets and sorghum per state population in 2015–2016 and their frequency of consumption.

Table 8 examines how state-wise per capita production was related to the frequency of consumption of millets through ordered probit regression. The covariates included in the model were the age dummy, gender dummy, and income dummy. The standard errors were clustered at the site level to account for intra-site repetition in the value of production. The results showed no statistically significant relationship between state-wise per capita production and the frequency of consumption in the urban areas, where age, gender, and income factors were controlled for. Lastly, younger people and women consumed millets less frequently, whereas people with low incomes consumed millets more frequently. An investigation of the distributional effects ( Table 9 ) to ascertain the marginal effects of state-wise per capita production on different levels of consumption frequency revealed that production and consumption exhibited a U-shaped non-linear relationship, suggesting that older people consumed more millets when the consumption level is in the low range. Likewise, being a woman and having low income was associated with consuming the crops less frequently.

Table 8 . Frequency of consumption of millets and sorghum and production per state population: ordered probit regression.

Table 9 . Marginal effects of state-wise per capita production of millets and sorghum on log odds of frequency of consumption in the urban areas ( n = 13,840).

Discussion and Policy Implications

Millet campaigns and promotions implemented in the past few years may be the reasons for the higher recognition of millets among the young age group. The individual ability to recognize millets varied across states, in line with the diverse agro-ecologies and contrasting cropping patterns across India ( Tsusaka and Otsuka, 2013 ). Frequent consumers were in Bengaluru, which is not surprising given its reputation for being an advanced city for organic and health foods including millets ( Anbukkani et al., 2017 ). It may be noted that Karnataka state, of which Bengaluru is the capital, was the first Indian state to have a Millet Mission and to launch the annual national millet fair in January 2017, which promoted traditional millets to be brought back as staples and popular modern food.

Although millets can be easily incorporated into almost all popular rice- and wheat-based recipes, one of the reasons for not consuming millets regularly is the lack of knowledge on how to incorporate or cook them. Currently, a few recipes are widely used in communities to cook millets. These include finger millet balls, finger millet porridge, millet chapattis/rotis, and finger millet malt. The relationship between demographic characteristics and the attitude of farm women toward value-added products of finger millet were studied previously ( Kowsalya et al., 2017 ), wherein it was concluded that when farm women were well-trained, there was a favorable attitude toward value addition of finger millet-based products. This, along with the consumer survey results, suggests the need for training on value addition for traditional smart foods, such as millets ( Anitha et al., 2019a , b ), and that preparing millets in a culturally appropriate manner helps in improving their acceptability. The model for introducing millets in communities and schools in an acceptable manner and how they can change perceptions and influence food preferences in a positive manner have been demonstrated previously ( Diama et al., 2020 ; Wangari et al., 2020 ). Equally important is understanding the initial knowledge, practices, and individual attitude toward these traditional crops while planning and implementing any nutrition-related interventions using them. A study ( Singh and Raghuvanshi, 2012 ) on knowledge, perceptions, and practices by 111 diabetes individuals reported that 55% of the participants consumed millets because it was a habit from childhood and only 26% of them reported that they ate it because they liked it. However, 11% of the respondents reported that they had no reason to consume millets. The reason for not consuming these grains was either because they were not prepared at their homes (20%) or were not part of their food from childhood (26.6%). Some of them reported that it was advised not to consume them, and 20.6% of them reported that there was no particular reason to not consume them. This shows that if millets were not eaten from childhood, there was no incentive or trigger for consuming them, hence the importance of raising awareness and inculcating good practices from childhood in order to develop a healthy population. However, the current study clearly demonstrated that the major reason for consuming millets was the prevalence of a health issue. A small percentage of people (11.8%) said that it was consumed due to the habit of it being eaten at home; while a significant percentage of people (39.2%) said they did not eat millets because of cultural habits of it not being eaten at home. This highlights the importance of influencing attitudes and practices for millets to become a common food in the household, resulting in more consumption. The result also shows that targeting the person/people who most influence what is eaten at home can have a multiplier effect on consumption.

In summary, health- and wellness-related issues were by far the major factors influencing consumption of millets in urban areas, with 58% of the interviewees stating so. Consumers with a health issue seemed to be the lowest hanging fruit with regard to market segments that were early adopters of millets, especially women. Consumers wanting to lose weight were also early adopters, again especially among women. Similar results were observed in the previous studies on consumer motives, attitude and purchase preferences for health and organic food products, showing that the health factor was the most important motive behind their selection and purchase ( Syah and Yuliati, 2017 ; Nandi et al., 2016 ).

Furthermore, a large gap was identified between people who were health conscious (91%) and those who knew that millets were healthy (40%; Figure 6 ). While some health benefits of millets were recognized, such as its role in preventing lifestyle-related non-communicable diseases, there were several other health benefits not well-known previously. A recent systematic review and global meta-analysis of 65 studies on 11 types of millets shows that millets help manage and reduce the risk of developing type 2 diabetes ( Anitha et al., 2021a ). Another systematic review and meta-analysis of 19 studies shows that long-term consumption of millets can reduce cholesterol, triglyceride, low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), high-density lipoprotein cholesterol (HDL-C), body mass index (BMI), and hypertension, which is another piece of evidence of its potential in reducing the risk of developing cardiovascular diseases ( Anitha et al., 2021b ). Their richness in iron also helps in improving hemoglobin levels and iron status of the body ( Anitha et al., 2021c ). In particular, finger millet is rich in calcium and zinc, which are essential for growth and immunity. These nutritional and therapeutic effects of millets are vital and provide alternative ways to solve some of the global public health issues. The proportion of people aware of health benefits of millets being 40% implies a large proportion of potential consumers and a significant knowledge gap. This result is also supported by an earlier study in Tamil Nadu that people had little knowledge of millets in comparison with oats ( Sreedhar and Shaji, 2017 ). Learning the actual health and nutritional benefits would increase consumption of millets. It is recognized that reaching the mainstream market may be challenging and would require more than just awareness raising.

Figure 6 . Gap in respondents who are health conscious vs. their knowledge on millets health benefit.

However, as family customs strongly influence what people eat at home, influencing the decision makers at households would have a ripple effect on consumption and be a major way to reach male consumers. Taste was observed to be a major reason why the respondents did/did not eat more millets, indicating that health awareness alone would not significantly boost millet consumption. Together, these insights showed the need for tasty products and simple recipes made from millets. As millets are mostly eaten as traditional porridge, there seem to be abundant opportunities to grow the market through ready-to-eat and ready-to-cook convenience foods and cookies, among others.

Overall, it is recognized that the market for millets would expand with appropriate awareness campaigns targeting different segments, especially through social media channels that were found to be the major sources of information on health and food. It would also be important to introduce tasty, modern, and convenient products into markets that are more easily accessible.

The findings of this study may be useful for policymakers as well as different stakeholders, e.g., food companies, government entities, nutritionists, development organizations, and researchers, who intend to promote consumption of millets under various government programs by improving awareness and delivering marketing campaigns. Specific consumer segments should be identified based on the research evidence, while the understanding of consumer awareness and rationale for eating or not eating millets may potentially be valuable inputs to public health debate. In particular, this may be useful for the Government of India Millet Mission, individual state Millet Missions, and the potential upcoming UN International Year of Millets (2023). The information may also help design nutrition behavioral change programs in urban settings.

The shopping centers where the surveys were conducted had good footfalls, with a wide variety of visitors. Nevertheless, the data were geographically localized, and the interviewees resided mainly in major urban cities. Future studies should attempt to obtain similar data on consumption, knowledge, and attitudes at the rural and peri-urban levels to compare various consumer segments and to develop better understanding of millet utilization. Moreover, repeated studies should be conducted to track these changes over time and the influences on changed behavior.

Little has been formally studied about urban consumers' knowledge, attitudes, and practices related to millets despite growing health consciousness among people, increasing non-communicable diseases in India, and the nutritional potential of millets. The survey involving over 15,000 face-to-face interviews across seven major cities in India is arguably the largest survey on consumers about millets. A key aim of this study was to understand the motivation of consumers and how best to position millets in any campaigns while planning agriculture-based nutrition interventions to improve the market, consumption, and nutritional status. The findings imply a need to more actively promote the benefits of millets and to create awareness of various ways of cooking millets or creating millet products to satisfy taste preferences and change the perception of millets, which would in turn lead to an increase in their consumption.

Data Availability Statement

The original contributions presented in the study are included in the article/ Supplementary Materials , further inquiries can be directed to the corresponding author/s.

Ethics Statement

Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study.

Author Contributions

JK-P: conceptualization, methodology, investigation, review and editing, and resources. SA, TWT, and RB: validation, formal analysis, data curation, and writing original draft. KM, RH, and MB: methodology, validation, and first analysis. SU, PK, SN, and AJ: writing—review and editing. All authors contributed to the article and approved the submitted version.

This research was funded by Smart Food endowment fund, ICRISAT.

Conflict of Interest

KM was employed by company SR Global Media and Research Pvt. Ltd. RH was employed by Thought Folks Digital.

The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher's Note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

Acknowledgments

This work was undertaken as part of the Smart Food initiative led by ICRISAT, FARA, CORAF, FANRPAN, and APAARI and coordinated jointly in India with IIMR. The authors are grateful to a range of people for their inputs: the expert panel for reviewing the survey—Ravula Padmaja, Jerome Bossuet, and Carl Hinrichsen (ICRISAT staff/consultants) and Sridhar Iriventi (Founder and Managing Director of Go Bharathi Agro Industries); and Ismail Mohamad (ICRISAT) for generating the map.

Supplementary Material

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fsufs.2021.680777/full#supplementary-material

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Keywords: millets, sorghum, health benefit, knowledge and practice, consumer behavior

Citation: Kane-Potaka J, Anitha S, Tsusaka TW, Botha R, Budumuru M, Upadhyay S, Kumar P, Mallesh K, Hunasgi R, Jalagam AK and Nedumaran S (2021) Assessing Millets and Sorghum Consumption Behavior in Urban India: A Large-Scale Survey. Front. Sustain. Food Syst. 5:680777. doi: 10.3389/fsufs.2021.680777

Received: 15 March 2021; Accepted: 29 June 2021; Published: 13 August 2021.

Reviewed by:

Copyright © 2021 Kane-Potaka, Anitha, Tsusaka, Botha, Budumuru, Upadhyay, Kumar, Mallesh, Hunasgi, Jalagam and Nedumaran. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Seetha Anitha, s.anitha@cgiar.org ; dr.anithaseetha@gmail.com

This article is part of the Research Topic

Smart Food for Healthy, Sustainable and Resilient Food Systems

Distribution of Market Power, Endogenous Growth, and Monetary Policy

Yumeng Gu, Sanjay R. Singh

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2024-09 | March 28, 2024

We incorporate incumbent innovation in a Keynesian growth framework to generate an endogenous distribution of market power across firms. Existing firms increase markups over time through successful innovation. Entrant innovation disrupts the accumulation of market power by incumbents. Using this environment, we highlight a novel misallocation channel for monetary policy. A contractionary monetary policy shock causes an increase in markup dispersion across firms by discouraging entrant innovation relative to incumbent innovation. We characterize the circumstances when contractionary monetary policy may increase misallocation.

Article Citation

Gu, Yumeng, and Sanjay R. Singh. 2024. “Distribution of Market Power, Endogenous Growth, and Monetary Policy,” Federal Reserve Bank of San Francisco Working Paper 2024-09. Available at https://doi.org/10.24148/wp2024-09

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Abstract: Reference resolution is an important problem, one that is essential to understand and successfully handle context of different kinds. This context includes both previous turns and context that pertains to non-conversational entities, such as entities on the user's screen or those running in the background. While LLMs have been shown to be extremely powerful for a variety of tasks, their use in reference resolution, particularly for non-conversational entities, remains underutilized. This paper demonstrates how LLMs can be used to create an extremely effective system to resolve references of various types, by showing how reference resolution can be converted into a language modeling problem, despite involving forms of entities like those on screen that are not traditionally conducive to being reduced to a text-only modality. We demonstrate large improvements over an existing system with similar functionality across different types of references, with our smallest model obtaining absolute gains of over 5% for on-screen references. We also benchmark against GPT-3.5 and GPT-4, with our smallest model achieving performance comparable to that of GPT-4, and our larger models substantially outperforming it.

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Managing Diabetes Mellitus With Millets: A New Solution

Pragya agrawal.

1 Anatomy, Datta Meghe Medical College, Datta Meghe Institute of Medical Science (Deemed to be University) Wardha, Nagpur, IND

Brij Raj Singh

Ujwal gajbe, minal a kalambe.

2 Obstetrics and Gynaecology, Datta Meghe Medical College, Datta Meghe Institute of Medical Science (Deemed to be University) Wardha, Nagpur, IND

Maithili Bankar

3 Medical Education Unit, Datta Meghe Medical College, Datta Meghe Institute of Medical Science (Deemed to be University) Wardha, Nagpur, IND

Diabetes mellitus (DM) is the leading cause of morbidity and mortality, and the disease's prevalence is increasing with each passing day. DM can be prevented and controlled with modifications to the diet, especially by incorporating millet in the diet. Throughout history, eating habits have been recognized for their significant contribution to promoting health and wellness by eating foods rich in nutrients. Millet is an underutilized food crop with many benefits for health, with the most beneficial being low glycemic index, high fiber content, polyunsaturated fatty acids (PUFA), non-acid-forming potential, and gluten-free. In addition to staple food crops, such as wheat, rice, and foxtail millet, millets are still highly nutritious and beneficial and have great potential to help the world combat the food insecurity many countries face today. Millets are in the top positions of recommended dietary charts with their numerous health benefits and antioxidant properties. 

Introduction and background

In the current environment, with increasing technological access, humans have headed toward a more sedentary and stressful life, with a lack of well-balanced dietary intake and sleep. India has become a hub for diseases such as diabetes mellitus (DM), hypertension, obesity, atherosclerosis, heart diseases such as ischemic cardia, angina, and cardiac arrest, and stroke in people in much lower age groups, even in their mid-thirties and forties [ 1 , 2 ]. DM is characterized by a complex pathogenesis. Type 1 DM or insulin-dependent DM is an autoimmune disorder characterized by T-cell-mediated destruction of β-cells of Islets of Langerhans of the pancreas which results in a deficiency of insulin. Type 2 DM or non-insulin-dependent DM is caused either due to insulin resistance or β-cell dysfunction. Exhaustion of glucose transporters in the intestine and kidney is also a line of cause for DM [ 3 , 4 ]. It is a lifestyle-related disorder and can be prevented and controlled with changes in diet along with prescribed medications. Dietary interventions have played a crucial role in the treatment of DM since the golden age of the great ancient Ayurvedic practitioner Sushruta, who had testified that a person’s dietary habits, in addition to other etiological factors such as hormonal imbalance and poor dietary habits, were one of the leading causes of DM [ 5 ]. In fact, according to medical history, a diet at the level of starvation was the only treatment for this disease before the discovery of insulin [ 6 ]. Today, this carousel has changed from Allen’s starvation diet to a diet rich in carbohydrates, fats, and dietary fibers, and a high intake of millet-based dietary fiber controls glycemia, hyperinsulinemia, and lowers plasma lipids in patients with type 2 DM [ 5 ].

In addition to staple food crops, such as wheat and rice, which people have been eating for years, millet remains highly nutritious and beneficial, but it is an underutilized crop that has a multitude of benefits for health; the most beneficial are low glycemic index (GI), high fiber content, polyunsaturated fatty acids (PUFA), non-acid-forming potential, and being gluten-free [ 7 ]. Millets are nutrients rich in vitamins, minerals, proteins, essential fatty acids, energy, carbohydrates, plant chemicals, and non-glycemic polysaccharides [ 7 - 9 ]. Millet grains show huge benefits in their resistance to drought and high-yield production in areas with less water availability [ 10 ].

Incorporating millets into the diet along with regionally available staple food crops and vegetables has been the greatest area of interest because millets provide more significant health benefits due to their high fiber, minerals, vitamins, macro- and micronutrients, and phytochemicals and can help combat chronic disorders. Millets also have great potential to help the world combat the food insecurity that many countries are facing today [ 8 ]. Despite numerous benefits, millet consumption has been restricted only to conventional communities, poverty, and drought-stricken across the globe due to a lack of awareness among people. They are known as ‘orphan cereals’ due to their neglected use [ 11 ]. Incorporating millet into the diet may seem difficult initially, but in no time, it can become a no-brainer and a solution to numerous lifestyle-induced health problems [ 12 ]. This article aims to highlight the nutritional benefits of millet and its efficacy in controlling, managing, and preventing DM.

What are millets and their consumption over the years?

Millets are grains that are considered one of the first cultivated cereals in agricultural history. They are small-seeded cereal grasses or coarse grains that belong to the Poaceae family and are widely used as the main source of food in the arid regions of developing countries around the world and also serve as feed in developed countries [ 13 ]. It is a rain-fed crop that requires minimal irrigation and can be easily cultivated in drought-prone areas where annual precipitation is lower than normal. Millets are widely cultivated in semi-arid tropical regions of Asia, India, China, and Africa [ 14 ]. Of the total 8000 species of millets, only 35 species comprising 20 different genera have been domesticated to date for food and feed [ 15 ]. Millets are an important part of Indian cuisine and many varieties are consumed. Ragi or finger millet, bajra or pearl millet, jowar, and sorghum are among the most popular millets in India [ 12 ]. Foxtail millet, also known as kangani, is another variety that is particularly prevalent during spiritual fasts. Additionally, barnyard millet is a type of millet often consumed in Indian and Japanese cuisine. It is possible that one’s ancestors, specifically grandparents, incorporated a significant amount of millet into their diet. As evidenced by an age-old Kannada adage, ‘A rice consumer is similar to a bird in terms of weight; a jowar consumer exhibits the fortitude of a wolf; while a Ragi consumer tends to be in good health, free from diseases’ [ 7 ]. India is recognized as the leading producer of millets worldwide, and as a result, millets have been a fundamental aspect of Indian cuisine for generations. India’s annual millet production accounts for approximately 40.20% of the total [ 16 ]. The consumption of millets in the Indian diet saw a significant decline after the advent of the Green Revolution in 1965, during which rice and wheat gained wider acceptance among the populace compared to other locally grown crops [ 17 ]. In recent times, there has been renewed interest in millets within Indian agronomy, after a prolonged period of neglect.

Distribution of millets in India

India is known for its diverse milling with a series of eight different species such as foxtail millet, finger millet, small millet, barnyard millet, sorghum, kodo millet, proso millet, and pearl millet, which are growing in different regions [ 18 ]. These millets serve as a significant food crop in India, either as a main staple or as part of the seasonal rotation with other agricultural products such as pulses, spices, condiments, and oilseeds [ 19 ]. Pearl millet and sorghum are widely grown in the dry areas of Gujarat, Rajasthan, Haryana, and Uttar Pradesh [ 20 ]. Sorghum is a major crop in parts of central India, including Telangana, Maharashtra, and Andhra Pradesh, where it is grown as one of the main food crops [ 21 ]. In Tamil Nadu and Gujarat, finger millet is very often cultivated. Despite India's rich cereal diversity, the consumption of cereals has declined over the past decades.

Nutritional benefits of millets

Bioactive Compounds Present in Millets

Millet’s seed coat, commonly known as bran, contains a significant concentration of essential nutrients, dietary fibers, and bioactive compounds such as tannins [ 22 ]. A diet regimen that incorporates a significant amount of finger millet seed coat has been shown to confer various health benefits. These include reducing inflammation, maintaining a healthy plasma lipid profile, alleviating oxidative stress, modulating the expression level of several obesity-related genes, and increasing the beneficial bacteria population of the gastrointestinal tracts such as lactic acids and bifidobacterial in a mice-based study [ 23 ]. The seed cover contains minerals such as calcium, magnesium, iron, zinc, and phosphorus, as well as globulin, albumin, and prolamin. Millets are silos of rich bioactive compounds that support the body, as shown in Figure  1 .

The polyphenols present in the millet seed layer enrich them with antioxidant properties along with anti-aspirin properties. A large amount of phytic acid present in millets, especially finger millets (ragi), reduces carbohydrate digestibility and mitigates postprandial blood glucose levels [ 24 ]. Therefore, finger millet has a potential as a food option for diabetics. Finger millet contains twice the amount of calcium in milk and 10 times more calcium than brown rice, wheat, and corn. Consumption of finger millet during and after pregnancy and lactation can provide significant benefits to maternal and child bone health and prevent osteoporosis. Calcium provides structure and rigidity to the body and mediates vascular and muscular contractions and nerve signal transmission [ 25 - 27 ]. Therefore, a balanced calcium dietary intake is recommended because excessive calcium is linked with mortality and causes vascular events in people receiving calcium supplementation [ 28 , 29 ]. The prebiotic components inherent in millets are metabolized by indigenous bacteria in the human gut to produce beneficial short-chain fatty acids and probiotics from the colon, which have been shown to possess antidiabetic properties [ 30 ]. Foxtail millet is particularly rich in resistant starch, which has the ability to delay gastric emptying and decrease post-consumption blood glucose levels [ 31 ]. Sorghum is enriched with prolamin (kefirin), a protein that, when cooked, becomes comparatively less digestible compared to proteins present in other cereals [ 32 ]. Pearl millet (bajra) is rich in zinc, iron, dietary fibers, and omega-3 fatty acids, which provide antioxidant properties when consumed [ 14 ]. Fibers rich in millets show a positive change in glycol-lipid parameters. So, they turned out to be the best rice alternative. Millets possess a significant concentration of critical amino acids, including phenylalanine, methionine, leucine, and isoleucine. In addition to these, they contain enough concentrations of vitamin E, vitamin B, calcium, iron, proteins, minerals, riboflavin, and thiamine present in them. Kodo millets act as a barrier to hyperlipidemia due to their high lecithin content and better seed viability [ 33 ]. Gluten-free teff millet can be used as an alternative to bakery items. Proso millet is a reservoir of lecithin, B-complex vitamins, and critical amino acids that promote neural health [ 34 ].

Benefits of Millets for Various Health Ailments 

Millets provide an approximate energy yield of 320-370 kcal per 100 g of millet consumption [ 35 ]. These substances exhibit the properties of antioxidants, immune modulators, and detoxifiers. They improve gastrointestinal and cardiovascular health and prevent the occurrence of cancers, celiac diseases, diabetes, hypertension, hyperlipidemia, duodenal ulcers, Parkinson’s disease, etc. [ 8 , 36 ]. Researchers have reported that millet intake increases the amount of high-density lipoproteins in plasma and regulates cholesterol metabolism [ 12 , 37 ]. Regular millet consumption can reduce the incidence of hormone-dependent cancers, such as breast cancer, and reduce the risk of cardiovascular disease in post-menopausal women. Millets are also known to slow the process of aging in humans [ 37 ]. Millets have higher levels of essential amino acids. Pearl millet is rich in arginine, threonine, valine, isoleucine, and leucine. Finger millet contains a balanced amount of essential amino acids. It contains higher amounts of lysine, valine, and threonine as compared to other varieties of millet. Proso millet contains the essential amino acids in significantly larger quantities, except for lysine. Little millet is a rich source of sulfur-containing amino acids including cysteine and methionine. The presence of these amino acids in millets indicates the potential benefits of millets in human health [ 38 ]. The health benefits of the most popular millets found in the Indian subcontinent are listed in Table  1 .

The GI of millet

The GI is the ability of foods to change blood glucose levels. Foods with higher GIs cause rapid increases in blood sugar levels, whereas foods with lower GIs cause gradual or steady increases in blood sugar levels. Seventeen studies out of a systematic review of 19 studies have shown a general reduction not only in blood sugar levels but also in serum cholesterol and serum triglycerides in patients who consume foods lower on the side of the GI [ 12 ]. Millets show a score between 40 and 70 on the GI chart, which is less than the GI value of wheat, refined flour, rice, and maize [ 40 ]. The consumption of proso millets showed a lower GI than those produced with wheat and corn. The GI and protein composition of different varieties of millet shown in India are shown in Table ​ Table2 2 [ 41 ]. 

Food medicine for DM

DM is characterized by a disturbance in body glucose homeostasis along with a disturbance in the levels of carbohydrates, proteins, and fats in the body. Hyperglycemia not only results in DM but the onset of DM paves the way for the development of many diseases along with it. A common feature of many non-communicable diseases is mitochondrial dysfunction as an underlying pathology. Mitochondrial perturbations are upstream of insulin resistance [ 42 ]. The most common ones include atherosclerosis, diabetes retinopathy, fractures due to demineralization, muscle fatigue, and renal problems [ 43 ]. Research has shown that diabetics have higher chances of kicking the bucket due to respiratory failure and multiple organ failure than non-diabetics [ 44 ]. Today, when India has become the most populous nation in the world, at the same time nearly 8-10% of its diabetic population is in the age group of 20-70 years, which is becoming a liability for a country like ours where a maximum of its population falls under the category of youth. India is considered the diabetic capital of the world [ 45 ]. It has been predicted that within the next decade, the number of cases of diabetes will exceed 350-450 million [ 37 ]. There has been a significant increase in cases of diabetes throughout the world due to an immense increase in population, aging, urbanization, increased obesity, and decreased physical activity.

Therefore, diet management is the central and most economical way to manage DM and the complications associated with it. Various diabetes associations across the globe offer guidelines for the consumption of adequate amounts of carbohydrates, proteins, fats, fibers, and sodium in the diet to promote healthy eating habits among individuals with diabetes. According to the American Diabetes Association (ADA), it is recommended that carbohydrates contribute 45-60% of the total calories, proteins 15-20%, and fats 25-35%. Also, a minimum of 14 g of fiber per 1,000 calories should be consumed, while at the same time, sodium intake should be limited to less than 2,300 mg per day. Similarly, the Canadian Diabetes Association (CDA) suggests a comparable distribution of macronutrients, with an emphasis on a daily fiber intake of 25-50 g. The British diabetes guidelines are close to the ADA recommendations, although they propose a slightly lower fat intake of 30% or less of total calories. The European Diabetes Research Association (EASD) also promotes similar guidelines for carbohydrate, protein, and fat intake, highlighting a daily fiber consumption of at least 25 g and restricting sodium intake to 2,000 to 2,400 mg per day. These associations strive to provide comprehensive nutritional guidance to people with diabetes, advocating for a balanced diet that supports general health and aids in blood sugar control, as shown in Table ​ Table3 3  [ 46 ].

g, grams; mg, milligrams.

Millets stand by as the ideal food crop for people with diabetes according to the criteria set by leading associations. The high fiber content and phenolic content of the diet make millet, especially foxtail millet, very fruitful for DM [ 37 ]. Diabetics show a major sign of polyphagia and frequent food cravings. Millets reduce the duration of gastric emptying to maintain constant postprandial body glucose homeostasis [ 47 ]. Polyphenolic ligands have an inhibitory effect on alpha-glucosidase and pancreatic amylases to reduce postprandial hyperglycemia by inhibiting the enzyme hydrolysis of complex carbohydrates [ 48 , 49 ]. Millets contain slowly digested starch that extends the digestion and absorption of carbohydrates in the intestine. Compared to widely consumed rice, millet releases less glucose into the blood for a longer period of time, which is attributable to diabetes prevention. Millets help in the management of body weight, which is of utmost importance in diabetic patients. Pearl millet increases insulin sensitivity and reduces triglyceride levels in the body.

How to incorporate millet into the diet

Millets are the cereals of today that can be very easily mixed into a diet. Initially, a low amount of millet should be incorporated into the diet with a gradual increase over the period. Traditionally, millets were puffed, flaked, and popped to be consumed in the diet [ 50 ]. Germinating and fermenting millet improve its nutrient availability while, at the same time, excessive polishing, grinding, and dehulling reduce its nutrient quality. Millets can be consumed at any time of the day. People are of the misconception that healthy food cannot be tasty. Millets break these misconception shackles and can be consumed with any food item of choice. Millets can be replaced with rice in the diet and compensate for any delicacy that requires rice as its main ingredient. A portion of millet can not only be consumed as salad or soup, but millet flour can be used to make chapattis (flattened Indian bread), dosas (fermented Indian bread), and bread to eat with vegetables, legumes, and pulses of choice. Porridge and kheer (traditional Indian preparation made with milk) made from millets, especially pearl millets, are widely consumed in the Rajasthan and Gujarat regions during winter [ 51 ]. Recent times have seen the emergence of noodles, vermicelli, pasta, bakery products, and sweets made of millet, especially finger millet [ 27 ]. One should try various varieties of millets available on the market, then decide which one suits the body the most.

Conclusions

Millets are ‘future crops’ that have the potential to merge as a powerful and effective solution to various metabolic diseases such as DM due to the high levels of micronutrients and macronutrients present in them. There remains an urgent need to develop more technologies to overcome the antinutrient property of millets to improve the industrial-scale processing of millets. Physicians, nutritionists, and patients themselves should try to incorporate millet into their diet and follow a strict, balanced, and planned diet in combination with regular exercise or walking. No single food provides 100% nutrients, so it is a prerequisite to incorporate them wisely into our diet in combination with other food sources. A meal comprising a combination of pulses, millet, and functional foods is the ideal meal.

The authors have declared that no competing interests exist.

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• 27 March 2024

Tweeting your research paper boosts engagement but not citations

• Bianca Nogrady

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Even before complaints about X’s declining quality, posting a paper on the social-media platform did not lead to a boost in citations. Credit: Matt Cardy/Getty

Posting about a research paper on social-media platform X (formerly known as Twitter) doesn’t translate into a bump in citations, according to a study that looked at 550 papers.

The finding comes as scientists are moving away from the platform in the wake of changes after its 2022 purchase by entrepreneur Elon Musk.

An international group of 11 researchers, who by the end of the experiment had between them nearly 230,000 followers on X, examined whether there was evidence that posting about a paper would increase its citation rate.

“There certainly is a correlation, and that’s been found in a lot of papers. But very few people have ever looked to see whether there’s any experimental causation,” says Trevor Branch, a marine ecologist at the University of Washington in Seattle and lead author on the paper, published in PLoS ONE last week 1 .

Every month for ten months, each researcher was allocated a randomly selected primary research article or review from a journal of their choice to post about on their personal account. Four randomly chosen articles from the same edition of the journal served as controls, which the researchers did not post about. They conducted the experiment in the period before Elon Musk took ownership of what was then known as Twitter and complaints of its declining quality increased.

‘Nail in the coffin’

Three years after the initial posts, the team compared the citation rates for the 110 posted articles with those of the 440 control articles, and found no significant difference. The researchers did acknowledge that their followers might not have been numerous enough to detect a statistically significant effect on citations.

The rate of daily downloads for the posted papers was nearly fourfold higher on the day that they were shared, compared with controls. Shared papers also had significantly higher accumulated Altmetric scores both 30 days and three years after the initial post. Calculated by London-based technology company Digital Science, an Altmetric score, says Branch, is a measure of how many people have looked at a paper and are talking about it, but it’s not a reliable indicator of a paper’s scientific worth. “It’s thoroughly biased by how many people with large followings tweet about it,” he says.

The findings echo those of information scientist Stefanie Haustein at the University of Ottawa, whose 2013 study 2 found a low correlation between posts and citations.

Haustein says the problem with using posts as a metric is that, even a decade ago, there was a lot of noise in the signal.

“We actually showed that a lot of the counts on Twitter you would get were bots, it wasn’t even humans,” says Haustein, who wasn’t involved in the new study.

She says the more recent departure of scientists from the platform has been the final nail in the coffin of the idea that posting could increase citations.

doi: https://doi.org/10.1038/d41586-024-00922-y

Branch, T. A. et al. PLoS ONE 19 , e0292201 (2024).

Article   PubMed   Google Scholar  

Haustein, S., Peters, I., Sugimoto, C. R., Thelwall, M. & Larivière, V. J. Assoc. Inf. Sci. Technol. 65, 656–669 (2014).

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• Quantum Research

Landmark IBM error correction paper published on the cover of Nature

Ibm has created a quantum error-correcting code about 10 times more efficient than prior methods — a milestone in quantum computing research..

27 Mar 2024

Rafi Letzter

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Today, the paper detailing those results was published as the cover story of the scientific journal Nature. 1

Last year, we demonstrated that quantum computers had entered the era of utility , where they are now capable of running quantum circuits better than classical computers can. Over the next few years, we expect to find speedups over classical computing and extract business value from these systems. But there are also algorithms with mathematically proven speedups over leading classical methods that require tuning quantum circuits with hundreds of millions, to billions, of gates. Expanding our quantum computing toolkit to include those algorithms requires us to find a way to compute that corrects the errors inherent to quantum systems — what we call quantum error correction.

Read how a paper from IBM and UC Berkeley shows a path toward useful quantum computing

Quantum error correction requires that we encode quantum information into more qubits than we would otherwise need. However, achieving quantum error correction in a scalable and fault-tolerant way has, to this point, been out of reach without considering scales of one million or more physical qubits. Our new result published today greatly reduces that overhead, and shows that error correction is within reach.

While quantum error correction theory dates back three decades, theoretical error correction techniques capable of running valuable quantum circuits on real hardware have been too impractical to deploy on quantum system. In our new paper, we introduce a new code, which we call the gross code , that overcomes that limitation.

This code is part of our broader strategy to bring useful quantum computing to the world.

While error correction is not a solved problem, this new code makes clear the path toward running quantum circuits with a billion gates or more on our superconducting transmon qubit hardware.

What is error correction?

Quantum information is fragile and susceptible to noise — environmental noise, noise from the control electronics, hardware imperfections, state preparation and measurement errors, and more. In order to run quantum circuits with millions to billions of gates, quantum error correction will be required.

Error correction works by building redundancy into quantum circuits. Many qubits work together to protect a piece of quantum information that a single qubit might lose to errors and noise.

On classical computers, the concept of redundancy is pretty straightforward. Classical error correction involves storing the same piece of information across multiple bits. Instead of storing a 1 as a 1 or a 0 as a 0, the computer might record 11111 or 00000. That way, if an error flips a minority of bits, the computer can treat 11001 as 1, or 10001 as 0. It’s fairly easy to build in more redundancy as needed to introduce finer error correction.

Things are more complicated on quantum computers. Quantum information cannot be copied and pasted like classical information, and the information stored in quantum bits is more complicated than classical data. And of course, qubits can decohere quickly, forgetting their stored information.

Research has shown that quantum fault tolerance is possible, and there are many error correcting schemes on the books. The most popular one is called the “surface code,” where qubits are arranged on a two-dimensional lattice and units of information are encoded into sub-units of the lattice.

But these schemes have problems.

First, they only work if the hardware’s error rates are better than some threshold determined by the specific scheme and the properties of the noise itself — and beating those thresholds can be a challenge.

Second, many of those schemes scale inefficiently — as you build larger quantum computers, the number of extra qubits needed for error correction far outpaces the number of qubits the code can store.

At practical code sizes where many errors can be corrected, the surface code uses hundreds of physical qubits per encoded qubit worth of quantum information, or more. So, while the surface code is useful for benchmarking and learning about error correction, it’s probably not the end of the story for fault-tolerant quantum computers.

Exploring “good” codes

The field of error correction buzzed with excitement in 2022 when Pavel Panteleev and Gleb Kalachev at Moscow State University published a landmark paper proving that there exist asymptotically good codes — codes where the number of extra qubits needed levels off as the quality of the code increases.

This has spurred a lot of new work in error correction, especially in the same family of codes that the surface code hails from, called quantum low-density parity check, or qLDPC codes. These qLDPC codes are quantum error correcting codes where the operations responsible for checking whether or not an error has occurred only have to act on a few qubits, and each qubit only has to participate in a few checks.

But this work was highly theoretical, focused on proving the possibility of this kind of error correction. It didn’t take into account the real constraints of building quantum computers. Most importantly, some qLDPC codes would require many qubits in a system to be physically linked to high numbers of other qubits. In practice, that would require quantum processors folded in on themselves in psychedelic hyper-dimensional origami, or entombed in wildly complex rats’ nests of wires.

In our paper, we looked for fault-tolerant quantum memory with a low qubit overhead, high error threshold, and a large code distance.

Bravyi, S., Cross, A., Gambetta, J., et al. High-threshold and low-overhead fault-tolerant quantum memory. Nature (2024). https://doi.org/10.1038/s41586-024-07107-7

In our Nature paper, we specifically looked for fault-tolerant quantum memory with a low qubit overhead, high error threshold, and a large code distance.

Let’s break that down:

Fault-tolerant: The circuits used to detect errors won't spread those errors around too badly in the process, and they can be corrected faster than they occur

Quantum memory: In this paper, we are only encoding and storing quantum information. We are not yet doing calculations on the encoded quantum information.

High error threshold: The higher the threshold, the higher amount of hardware errors the code will allow while still being fault tolerant. We were looking for a code that allowed us to operate the memory reliably at physical error rates as high as 0.001, so we wanted a threshold close to 1 percent.

Large code distance: Distance is the measure of how robust the code is — how many errors it takes to completely flip the value from 0 to 1 and vice versa. In the case of 00000 and 11111, the distance is 5. We wanted one with a large code distance that corrects more than just a couple errors. Large-distance codes can suppress noise by orders of magnitude even if the hardware quality is only marginally better than the code threshold. In contrast, codes with a small distance become useful only if the hardware quality is significantly better than the code threshold.

Low qubit overhead: Overhead is the number of extra qubits required for correcting errors. We want the number of qubits required to do error correction to be far less than we need for a surface code of the same quality, or distance.

We’re excited to report that our team’s mathematical analysis found concrete examples of qLDPC codes that met all of these required conditions. These fall into a family of codes called “Bivariate Bicycle (BB)” codes. And they are going to shape not only our research going forward, but how we architect physical quantum systems.

The gross code

While many qLDPC code families show great promise for advancing error correction theory, most aren’t necessarily pragmatic for real-world application. Our new codes lend themselves better to practical implementation because each qubit needs only to connect to six others, and the connections can be routed on just two layers.

To get an idea of how the qubits are connected, imagine they are put onto a square grid, like a piece of graph paper. Curl up this piece of graph paper so that it forms a tube, and connect the ends of the tube to make a donut. On this donut, each qubit is connected to its four neighbors and two qubits that are farther away on the surface of the donut. No more connections needed.

The good news is we don’t actually have to embed our qubits onto a donut to make these codes work — we can accomplish this by folding the surface differently and adding a few other long-range connectors to satisfy mathematical requirements of the code. It’s an engineering challenge, but much more feasible than a hyper-dimensional shape.

We explored some codes that have this architecture and focused on a particular [[144,12,12]] code. We call this code the gross code because 144 is a gross (or a dozen dozen). It requires 144 qubits to store data — but in our specific implementation, it also uses another 144 qubits to check for errors, so this instance of the code uses 288 qubits. It stores 12 logical qubits well enough that fewer than 12 errors can be detected. Thus: [[144,12,12]].

Using the gross code, you can protect 12 logical qubits for roughly a million cycles of error checks using 288 qubits. Doing roughly the same task with the surface code would require nearly 3,000 qubits.

This is a milestone. We are still looking for qLDPC codes with even more efficient architectures, and our research on performing error-corrected calculations using these codes is ongoing. But with this publication, the future of error correction looks bright.

Fig. 1 | Tanner graphs of surface and BB codes.

Fig. 1 | Tanner graphs of surface and BB codes. a, Tanner graph of a surface code, for comparison. b, Tanner graph of a BB code with parameters [[144, 12, 12]] embedded into a torus. Any edge of the Tanner graph connects a data and a check vertex. Data qubits associated with the registers q(L) and q(R) are shown by blue and orange circles. Each vertex has six incident edges including four short-range edges (pointing north, south, east and west) and two long-range edges. We only show a few long-range edges to avoid clutter. Dashed and solid edges indicate two planar subgraphs spanning the Tanner graph, see the Methods. c, Sketch of a Tanner graph extension for measuring Z ˉ \={Z} and X ˉ \={X} following ref. 50, attaching to a surface code. The ancilla corresponding to the X ˉ \={X} measurement can be connected to a surface code, enabling load-store operations for all logical qubits by means of quantum teleportation and some logical unitaries. This extended Tanner graph also has an implementation in a thickness-2 architecture through the A and B edges (Methods).

Fig. 2 | Syndrome measurement circuit.

Fig. 2 | Syndrome measurement circuit. Full cycle of syndrome measurements relying on seven layers of CNOTs. We provide a local view of the circuit that only includes one data qubit from each register q(L) and q(R) . The circuit is symmetric under horizontal and vertical shifts of the Tanner graph. Each data qubit is coupled by CNOTs with three X-check and three Z-check qubits: see the Methods for more details.

Why error correction matters

Today, our users benefit from novel error mitigation techniques — methods for reducing or eliminating the effect of noise when calculating observables, alongside our work suppressing errors at the hardware level. This work brought us into the era of quantum utility. IBM researchers and partners all over the world are exploring practical applications of quantum computing today with existing quantum systems. Error mitigation lets users begin looking for quantum advantage on real quantum hardware.

But error mitigation comes with its own overhead, requiring running the same executions repeatedly so that classical computers can use statistical methods to extract an accurate result. This limits the scale of the programs you can run, and increasing that scale requires tools beyond error mitigation — like error correction.

Last year, we debuted a new roadmap laying out our plan to continuously improve quantum computers over the next decade. This new paper is an important example of how we plan to continuously increasing the complexity (number of gates) of the quantum circuits that can be run on our hardware. It will allow us to transition from running circuits with 15,000 gates to 100 million, or even 1 billion gates.

Bravyi, S., Cross, A.W., Gambetta, J.M. et al. High-threshold and low-overhead fault-tolerant quantum memory. Nature 627, 778–782 (2024). https://doi.org/10.1038/s41586-024-07107-7

Start using our 100+ qubit systems

Keep exploring.

Exploring measurement error mitigation with the Mthree Qiskit extension

Computing with error-corrected quantum computers.

The era of quantum utility must also be the era of responsible quantum computing

Logical gates with magic state distillation