There is an old wisdom shared in almost all languages of the subcontinent – that all seeds are grains but not all grains can qualify to be used as seeds. Recently grains of 6 different millet varieties were processed at the Earth360 facility in Kadiri, A.P.. While part of the size based selection is done using a grader, the larger & heavier grains (the images in the left hand side column) are selected for seeds using multiple passes in a destoner. The remaining material (the images in the right hand side column) shall be collected and used for other purposes, including for processing to human edible forms.
– by Dr. Adithya Pradyumna, MBBS, MPH (London), PGDip (Environment)
editing assistance: Dwiji Guru.
The arguments presented regarding millets being goitrogenic, typically rely both on population level survey studies of goitre and on lab based biochemical studies. There are two stages to the argument:
1. Studies in some populations that consume millets as a staple have shown unusually high prevalence of goitre.
2. The alleged mechanism for this process is plausibly the presence of compounds (polyphenolics – flavonoids) which have anti-iodine metabolism and anti-thyroid activities, as has been apparently been demonstrated in animal and tissue studies.
What is goitre?
It is the term used to denote a swelling in the neck caused by the enlargement of the thyroid gland (due to whatever reason). Such an enlargement of the gland may be associated with normal secretion of thyroid hormone, or inadequate secretion (hypothyroidism) or increased secretion (hyperthyroidism). The most common reason for goitre is iodine deficiency, associated with either normal or low thyroid secretion (NHS, 2015).
Other factors accounted for/isolated?
The papers linking goitre to millet-consuming populations are based on survey data. It is unclear whether the analysis has adequately considered the potential role for alternative explanations, such as a general state of malnutrition or chronic low iodine intake. A preliminary search through Google Scholar has not revealed the presence of a systematic review on this subject, which would have helped clarify matters more easily.
One of the cited studies was conducted in Sudan, which showed that the urinary excretion of iodine (UIE) was normal in a population with 22% prevalence of goitre, which means the population probably consumed normal levels of iodine (at least in the short term), and so the goitre may have had something to do with the inappropriate metabolism of the iodine within the body (Elnour et al., 2000). The children with goitre had normal thyroid hormone levels, which may have occurred through compensatory enlargement of thyroid gland. Here the inference taken was that as the iodine levels in urine was normal, the high millet diet potentially did not allow appropriate metabolism. But it is important to also note that the researchers did not adequately study chronic iodine deficiency or document the diets completely (to understand sources of iodine and quantity of millet consumption), or other potential explanations for the phenomenon. A high prevalence of protein-energy malnutrition along with multiple vitamin deficiencies was also prevalent in this population, which could potentially explain, at least in part, the derangement in thyroid hormone metabolism.
In the cited Gujarat study (Brahmbhatt et al., 2000), there was UIE was low in 54% of the population (indicating low iodine intake at least in the short term) and mild to moderate goitre was seen in 23% of the children (indicating chronic iodine deficiency). This may indicate goitre due to low dietary intake itself (at least that would be the first suspect). UIE and goitre may not correlate due to these being indicators of acute vs chronic status of iodine respectively (Elnour et al., 2000). Surely there is a need for more hypothesis driven empirical research to understand the extent to which millet consumption can interfere with normal thyroid metabolism, and the other dietary conditions that predispose to such a situation (what percentage of diet, what combination of diet, how it is cooked etc).
Which of the millets are we talking about?
That some millets contain flavonoids (a goitrogenic substance) appears to be well known – pearl millet (Cordain, 2014), and in relatively smaller amounts in ragi (FAO, n.d.). A preliminary search has not revealed information on the presence of goitrogens in other millets. This point is important, as each millet is quite different from the other. Taxonomically the various millets are classified into more than 5 different genii under the family poaceae. There are so many differences- from structure to chemical composition, and hence nutritional composition- between say pearl millet, one of the most widely used naked grain millets in the world, and foxtail millet one of the most widely consumed of the husked grains classified under millets. It would be similar to saying hominids are the same.
How much & in what form?
Rats fed on fermented bajra (in animal studies) have resulted in goitre (Cordain, 2014). But the question now is how much bajra and in what form will one have to consume for it to be dangerous for thyroid metabolism? Each variety of millet possesses different levels of these compounds. Also, the method of preparation and cooking affects the level of these compounds. It may be worthwhile discussing the preparation method while discussing potential for risk in a particular context. A relatively old FAO document provides a great degree of details on preparation methods for millets (FAO, n.d.). Traditionally and locally employed approaches will need to be looked into in various millet consuming communities.
Risks and benefits weighed?
The same flavonoid compounds which are apparently anti-thyroid, have also been reported to be potentially very beneficial to health as anti-oxidants (from an anti-cancer and anti-aging perspective) (Shahidi and Chandrasekara, 2013). So, even if it comes to pass that millets may slightly increase risk of thyroid disorders, it will have to weighed against its role in reducing population risk to cancer and other age related disorders. This kind of calculation has been conducted in several other cases (such as for the questions on whether salmon should be consumed as they contain detectable levels of polychlorinated biphenyls or PCBs, where it has been recommended that eating salmon will still have far greater health benefits than the risks posed by trace levels of PCBs).
Iodine in the diet
Iodine is most abundant in fish. For those not consuming marine products, iodine is primarily obtained through vegetables and pulses. Iodine is present in the soil, but the content in soil is reducing due to various causes of mismanagement of soil. Iodine fortification of salt (NHS, 2015) has become the policy makers response to this apparent public health challenge. Some studies in India have indicated that a partial contribution to iodine deficiency, because of an inability to absorb Iodine, could be due to thiocynates in the diet. Those compounds are primarily seen in the brassica group of vegetables, and also in jowar. But some studies indicate that for thiocyanate to cause health impacts, the diet would need to be deficient in iodine (Agarwal, 2008).
One American endocrinologist stated: “Basically the goitrogens are challenges to the thyroid. But in the absence of iodine deficiency, substantial or prolonged ingestion of dietary goitrogens and lastly the absence of an underlying thyroid disorder, the risk in this country of having problems in this area are very, very low, almost minuscule. Again, that’s because the vast majority of people have adequate iodine levels to counteract the effect of goitrogens.” (Zimmerman, 2014) So, if we interpret this argument in the Indian context, where it has been estimated that approximately 350 million don’t take enough iodine in the diet (Pandav et al., 2013), the poor intake of iodine would need to shoulder a good part of the responsibility for hypothyroidism.
Opinion was also sought from Dr Anoma Chandrasekara, Head of the Department of Applied Nutrition of Wayamba University, Srilanka, who mentioned “My personal idea is millets can be a beneficial component in a balanced diet…. So if the area we consider is deficient in iodine and if there are no strategies to overcome the problem such as salt iodization, consuming foods (not only millet, but even some vegetables) that contain goitrogenic factors can aggravate the problem. But in societies in nutrition transition, millet like foods can contribute towards health food choices. I think moderation of food selection and balance of different food types should be key for optimal health. According to what I notice in Sri Lanka with occurrence of more and more NCDs, our traditional foods that had disappeared are appearing on the table again. Millet is one of them. We should promote millet like grains. But if iodine deficiency is a problem in the area need to address separately” (Chandrasekara, 2016).
Millets in traditional food systems
Millets have been consumed in local rural and adivasi/aboriginal communities for generations. Millets are almost never eaten exclusively (even in situation of extreme poverty it is eaten with salt and some spices, based on anecdotal reports) – it is consumed with other vegetables, pulses or meat. They are prepared in many different ways and some of these processes, such as malting, tempering prior to milling, and germination, have been studied and shown to reduce the levels of “anti-nutrients” (FAO, n.d.). one should note that some of these processes could affect the level of other nutrients.
For populations that have traditionally eaten millet diets, such as in Karnataka, there have not been reports or anecdotal exchanges of endemic goitre. There is scope for such a study in areas where millets consumption is prevalent even to this day.
There are several foods that contain goitrogens and a couple of millets have been identified to do so too. The level of these compounds present in various millets is still unclear and more studies are needed to identify that.
Millets are old food, very old in fact. And the notion and evidence of millets containing “anti-nutrients” is also not very new (FAO, n.d.). Millets, it appears, was and is primarily considered an important measure of food security for the poor from arid areas where nothing else grows. It is only recently that the health benefits of millets and their use disease management has increased their appeal to the whole population. There surely is some basis for calling them “healthy food”. There are warnings that there might be some not so desirable components too. But there are many communities around the world that have lived and survived primarily due to their millet centric diets.
It is preferred to have a reasonable diversity in diet, and in sufficient quantities to nourish ourselves. It appears that millets in a balanced vegetarian or non-vegetarian diet should not cause problems, especially one in which there is adequate iodine intake. Practicing the precautionary principle, in particular for pregnant mothers and children who are in greater need for normal thyroid metabolism to ensure appropriate brain and physical development, one should ensure adequate intake of iodine by consciously including Iodine rich foods or supplemented food items like iodized salt.
There are also ways in which millets can be cooked to reduce even the minor risk that may be associated with them, without losing any of its other health benefits. A diet that includes millets is especially beneficial from the glucose metabolism perspective. The many different millet options also offer an unparalleled opportunity for diversifying the cereal component of our diets.
Agarwal, K.N., 2008. Iodine Deficiency and Endemic Goiter: A National Tragedy. Indian Pediatr. 454–455.
Brahmbhatt, S., Brahmbhatt, R.M., Boyages, S.C., 2000. Thyroid ultrasound is the best prevalence indicator for assessment of iodine deficiency disorders: a study in rural/tribal schoolchildren from Gujarat (Western India). Eur. J. Endocrinol. Eur. Fed. Endocr. Soc. 143, 37–46.
Chandrasekara, A., 2016. Query regarding phenolics in millets.
Cordain, L., 2014. Millet: A Gluten-Free Grain You Should Avoid : The Paleo DietTM [WWW Document]. Paleo Diet. URL http://thepaleodiet.com/millet-gluten-free-grain-avoid/#.VtaDF9DGAgT (accessed 3.2.16).
Elnour, A., Hambraeus, L., Eltom, M., Dramaix, M., Bourdoux, P., 2000. Endemic goiter with iodine sufficiency: a possible role for the consumption of pearl millet in the etiology of endemic goiter. Am. J. Clin. Nutr. 71, 59–66.
FAO, n.d. Sorghum and millets in human nutrition [WWW Document]. FAO Corp. Doc. Repos. URL http://www.fao.org/docrep/t0818e/t0818e0j.htm (accessed 3.2.16).
National Nutrition Monitoring Bureau, 2003. Prevalence of micronutrient deficiencies (No. 22). National Institute of Nutrition, ICMR, Hyderabad, India.
NHS, 2015. Goitre [WWW Document]. NHS. URL http://www.nhs.uk/Conditions/Goitre/Pages/Introduction.aspx (accessed 3.2.16).
Pandav, C.S., Yadav, K., Srivastava, R., Pandav, R., Karmarkar, M.G., 2013. Iodine deficiency disorders (IDD) control in India. Indian J. Med. Res. 138, 418–433.
Shahidi, F., Chandrasekara, A., 2013. Millet grain phenolics and their role in disease risk reduction and health promotion: A review. J. Funct. Foods 5, 570–581. doi:10.1016/j.jff.2013.02.004
Zimmerman, R., 2014. Thyroid Doc: Kale Risks “Theoretical” But In Reality, Very Low To Minuscule [WWW Document]. Wburs Commonhealth. URL http://commonhealth.wbur.org/2014/01/thyroid-doc-kale-problems-theoretical-but-in-reality-very-low-to-minuscule (accessed 3.2.16).
Millets are special.
There are many different grains, at least 10 of them, that are broadly classified as millets. Millets are rain fed crops that have been cultivated for many a millennia in pretty much all parts of the world. If you are interested to read more about pre-historic food grains and our attempts to understand and reconstruct their movements back then, do check out this amazing resource from Cambridge University.
As one would expect of something done by generation after generation in many many places – there are thousands of varieties of each millet. Think about it, from an evolutionary perspective, each of these traditional local varieties have survived the floods, the droughts, the hail storms, and what not. Their resilience is also evident in how preferred a food source millets are to birds, grazing animals and many other players in the ecosystem. Each variety is a specialization to the local climate, soil and culture.
And most importantly, to our discussion here and to the broader appreciation of ‘the other’, each variation has its own bouquet of flavors, size and cooking characteristic. Grains from the same farm, cultivated by the same farmer will have a small variation from the normal based on whether the rains were normal, deficient or excess that year.
Given that most millets are short duration crops, and the period with grains on the plant (aka reproductive stage) is a fraction of that time, I would expect that the degree of influence that shortened day light would have on the quality of the grain would be significant and appreciable.
No wonder then that the foxtail millet grown on a east facing hill slope will cook and taste different from the foxtail millet harvested of the same seed but grown in the plains a few kms away.
So thus I rest my case that Millets are the new wine.
PS: I was inspired to write this after cooking and eating the heavenly kodo millet rice that from Kaulige Foods yesterday. Unfortunately, I did not take any photographs before it disappeared off our plates. I shall post about it in a few days when we cook this the next time.
Millets have a higher satiety index when compared to white paddy rice, i.e. one feels full and sated after eating a smaller quantity of millets as compared to white paddy rice. As one would expect the satiety index is not a very objective quantity. It is a statistical construct to quantify a subjective thing and hence should typically be considered as a range or as a comparative measure rather than an indicator of an absolute characteristic.
The satiety index for millets, generally speaking, is about 130 to 150% as that of white paddy rice. i.e. one would need to eat 1.3 to 1.5 cups of cooked white paddy rice to feel as full as one does after eating 1 cup of cooked millet rice. Little millet rice would be on the lower bound of this range while finger millet or pearl millet would be at the upper bound of this range.
With this in mind, let us now get down to planning a meal in which we will prepare a millet rice instead of white paddy rice.
Remember that white paddy rice typically needs 2 cups of water for each cup of dry rice measure, while 1 cup of a dry millet rice needs about 3 cups of water to cook. For some millet varieties this can be even up to 3.5 to 4 cups of water. The best way to identify the exact proportion is to prepare a small quantity and verify.
Now lets say that a family usually cooks 1 cup of white paddy rice for their meal. So this would mean that typically eat about 3 cups of cooked white paddy rice. Applying the satiety index proportion of 130%, we get 3/1.3 i.e. approximately 2.3 cups of cooked millet rice. Using a 1:3 proportion of water, we would need to use about 0.6 cups of dry millet rice and 1.8 cups of water.
Hope this helps ! Feel free to point out errors, ask clarifications …
Proportion of water
In general good unpolished millet rice when cooked with
- 1:2.5 times of water results in a dry and fluffy consistency
- 1:3.5 times of water results in a wet and fluffy consistency
Trial and error is the best way to confirm how much water is needed. Try cooking a small quantity and see whether result is satisfactory. Make appropriate corrections before arriving at the proportion that works best for you and your family. Please note that even for a particular millet, the preferred proportion might change on the source of the millet rice, especially the variety. So when starting a new packet of millets, play it safe and do a trial.
Open cooking millet rice
- use a wide based utensil
- bring water to a boil
- add the washed rice and
- open cook for about 15 minutes on a low flame
- close the lid partially, it will boil over if you close it fully
- once cooked, turn off the flame, sprinkle a hand full of water, close the lid tight and let sit for about 30 min.
- Fluff up the cooked rice after it has cooled down a bit
- Please note that mixing or using a ladle in a just cooked, hot millet rice will tend to mash it and give it a mushy consistency.
Millet rice using a pressure cooker
- Millet rice grains are smaller (and lighter) than paddy rice grains and they
- do not need as much pressure to cook
- get lifted off the container and splatter all over the inside of the cooker much easier than paddy rice grains
- The thickness of the layer with grains that get cooked to a mushy consistency can be minimized by using a pressure pan with a wider base rather than a tall cooker
- If using a (good and properly working) pressure cooker, simmer the flame once the pressure builds up close to the threshold level (the ‘weight’ begins to quiver/spin/dance, getting ready to lift up and vent steam/blow whistle)
- after a couple of minutes, turn off the flame; yes, the whistle does not need to blow.You will need to keep it on a low flame for a longer duration for Foxtail, Kodo and Proso millets. Little and Barnyard millets cook much quicker.
- put a cloth on top of the cooker (to reduce the rate at which it cools down) ! please make sure the flame has been turned off !
- once the pressure has dissipated, open the cooker, sprinkle a fist full of water, close the lid tight and let sit for about 30 min.
- fluff up the cooked rice after it has cooled down a bit
- Please note that mixing or using a ladle in a just cooked, hot millet rice will tend to mash it and give it a mushy consistency.
Hello world, I am a millet. If you have no clue as to who/what I am (damn Green Revolution!), this is a good place to find out more. If you have heard about me, this is still a good place to find out more.
This blog has been created as a space to document information about millets. You will be able to learn about the following:
We hope you will incorporate millets into your life and share your experience(s) with others using this blog as a forum for healthy discussion.