We are by now used to hearing about the advantages of the various millets as nutritious food that are easily digested, and which have added advantages for people with specialized diets (namely low GI and gluten-free). There are, however, a couple of negative issues one may come across: that millets are goitrogenic; and that they have their own forms of gluten. I'd like to air those here in the interests of wide coverage of millets' nutritional characteristics, and to elicit any relevant info from list subscribers.

1. Goitrogenic effects? There has been research including millets among the various foods containing compounds which interfere with iodine uptake or thyroid function. This quote from the Encyclopedia of Human Nutrition provides some context:

"Goitrogens are dietary substances that interfere with thyroid metabolism and can aggravate the effect of iodine deficiency. Most goitrogens do not have a major clinical effect unless they are consumed at high levels and iodine deficiency is present." https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/goitrogen (this page has several articles)

The compounds at issue in millets (as well as in soybeans, apparently) are flavonoids, which may act to "impair thyroid peroxidase activity," ("The Latest Research and Development of Minerals in Human Nutrition") https://www.sciencedirect.com/topics/veterinary-science-and-veterinary-medicine/goitrogen

I understand from our NAMA colleague Joni Kindwall-Moore that concerns at least one person has raised about millets in particular on this count are not widely held.

2. Other forms of gluten? A relative mentioned that one researcher (Peter Osborne, at https://www.youtube.com/watch?v=jnlZaMzZaSk ) proposes that all grains have some form of gluten, and that all of those may pose problems for gluten-sensitive people.

For context: "Gluten is a family of storage proteins — formally known as prolamins — that are naturally found in certain grains, such as wheat, barley, and rye.

"Many prolamins fall under the gluten umbrella, but they’re most commonly identified by the specific grains in which they’re found. For instance, glutenins and gliadins are the prolamins in wheat, secalins are found in rye, and hordeins are found in barley." https://www.healthline.com/nutrition/what-is-gluten

Dr. Osborne notes the following "forms of gluten" (i.e., prolamins) in three millets, and states that these grains plus oats, corn, and rice are "oftentimes considered to be gluten free even though technically they are not..." (at about minute 5:25 in his video):

* Millet (presumably proso, but this is not stated): panicin (40% of total protein)

* Sorghum: kafirin (52% of total protein)
* Teff: penniseitin (11% of total protein)

(The table with forms of gluten that is used by Dr. Osborne in his video can also be viewed at http://www.allergy-details.com/gluten-allergy-c/gluten-allergy-and-types-of-gluten/ )

On the other hand, a nice short item on millets and allergies notes that "Panicin is the prolamine gluten protein in [proso?] millet. Because this type of gluten does not activate celiac disease, it is considered gluten-free." https://www.allergy-details.com/gluten-free-diet/gluten-free-food-gluten-free-diet/millet/

I'll leave this here, with the caveat that I have no expertise in these issues, and so am not in a position to evaluate claims or research findings relating to them. I look forward to others' comments.

Don

Don Osborn, PhD

(East Lansing, MI, US)

North American Millets Alliance