In the past 20 years chia seeds have become an increasingly popular item in co-ops and health food stores primarily because of their high content of the healthful omega 3 fatty acid, alpha linolenic acid (ALA). Chia seeds have also been fed to domestic livestock and chickens to enrich their meat and eggs with omega 3 fats. I can endorse feeding chia seeds to animals, but have serious reservations when it comes to humans eating these seeds as staple foods. The table below shows the entire nutrient profile for a 100 gram serving of chia seeds.
At least on paper, it would appear that chia seeds are a nutritious food that is not only high in ALA, but also is a good source of protein, fiber, certain B vitamins, calcium, iron, manganese and zinc.
Unfortunately, in the game of human nutrition, the devil is almost always in the details. As is the case with many other plant seeds (e.g., cereal grains, legumes) chia seeds contain numerous antinutrients which reduce their nutritional value. If you look at the table above, notice the high phosphorous concentrations found in chia seeds. This revealing marker tells us that chia seeds are concentrated sources of phytate, an antinutrient that binds many minerals (calcium, iron, zinc, magnesium and copper) thereby making them unavailable for absorption. So, in our bodies, chia seeds actually become inferior sources of all these minerals. Similarly, the table suggests that chia seeds are good sources of vitamin B6. Unfortunately, in our bodies the utilization this vitamin from plant foods such as chia seeds is quite low, whereas bioavailability of B6 from animal products is quite high approaching 100%.
One of the unusual characteristics of chia seed Pinole or food products comes from a clear mucilaginous gel that surrounds the seeds. This sticky gel forms a barrier which impairs digestion, fat absorption and causes a low protein digestibility. Based upon animal and human studies, it is likely that other antinutrients together with this gel may promote a leaky gut, chronic systemic inflammation and food allergies.
Dr. Nieman and co-workers recently completed a study in humans who consumed 50 grams of chia seeds per day for 12 weeks. At the experiment’s end both men and women experienced increases in a blood inflammatory marker called interleukin 6 (IL-6). After 12 weeks the men’s blood levels of IL-6 increased 10.2 %, and the women’s increased 10.1%. Additionally, another inflammatory marker called monocyte chemotactic protein increased 6.9 % in the men and 6.1 % in the women. In support of the notion that chia seed consumption may adversely affect the immune system and promote inflammation is a rat study showing that after only one month high chia seed diets increased blood levels of IgE by 112.8 %. Because IgE is a marker for allergenic food proteins that are processed through the gut, chia seeds likely cause a leaky gut and food allergies. As you can see, the nutritional problems with chia seeds involve similar issues as with cereals grains – they simply are second-rate foods compared to meats, fish and fresh fruits and vegetables.
© Loren Cordain, Ph.D., http://thepaleodiet.com/seed-fatty-acid-composition/#.Vi0c17RViko