When one of my favorite researchers wrote on April 20 that "the potential adverse effects of long term, chronic chia seed consumption may outweigh the potential benefits," I took notice. Loren Cordain, Ph.D., is a professor in Colorado State University's department of health and exercise science. Dr. Cordain wrote one of the most intriguing books on nutrition, The Paleo Diet, which recommends that we avoid grains and dairy since our paleolithic ancestors weren't able to eat those foods.

Dr. Cordain's report in his April 10 newsletter is more detailed in his criticism of chia seeds. An excerpt is available online, but the guts of the chia seed report sells for $6.95 plus shipping and taxes.

My 2007 post here on chia seeds got lots of attention, including more comments -- 112 to date -- than any other. So I was concerned enough to contact the world's leading researcher on chia seeds.

Wayne Coates, Ph.D., is professor emeritus in the office of arid lands studies at the University of Arizona, Tucson. Dr. Coates has researched chia seeds for three decades and wrote the definitive book on the subject, Chia: Rediscovering a Forgotten Crop of the Aztecs (The University of Arizona Press, 2005).

Dr. Coates purchased a copy of the chia seed report. He shared it and his comments with me.

"I do not want to get into a long discussion about this," Dr. Coates writes, "but would like to make a few comments. In his article, Table 1 gives the nutrient profile for chia seeds. Interestingly he does not give the source of the data, and furthermore, he says it gives the 'entire' nutrient profile of chia seeds. In no way it is complete, and since the source is not identified, one can easily question its value as a reputable source.

"He talks about anti-nutrients in chia, yet he promotes flaxseed. The anti-nutrients in flaxseed are well-documented for both humans and animals. He criticizes the gel (which is soluble fiber) as possibly impairing fat absorption and the high fiber content as protein to be poorly absorbed. In some cases, there may be some negative effects, but the positive effects of consuming fiber in the diet in terms of bowel function and prevention of coronary heart disease are well-documented.

"He also does not like the fact that chia contains phytic acid. Phytic acid has been shown to have antioxidant, anticancer, hypocholesterolemic and other beneficial effects. So again, it is unclear why he states this is a negative aspect of chia.

"He also discusses the study by Nieman et al. and cites the author's statement that inflammatory markers increased. That is well and good, but even he notes that 'other confounding factors may have influenced the results.' In another study, which the authors listed as a preliminary study, he cites the results and states that IgE levels increased dramatically. The issue here is that the results were not statistically significant, and if you look at the standard deviation of the chia seed  treatment, it was almost as large as the mean. In other words, the study should not be cited as being relevant.