Interesting, thanks for compiling. For me specially this:
Some Food Materials That Can Inhibit Nutrient Absorption: Yeast (Saccharomyces Cerevisiae)
One food material that some manufacturers include in the products that exhibits decreased absorption of an important nutrient it contains is yeast. Folic acid is a nutrient that is critically needed by pregnant mothers because it is proven to reduce birth defects with the reduction of birth defects being greater at higher doses. Early studies (1947, 1952) showed that the folic acid contained in a food-type yeast (Sacchromyces cerevisiae) exhibited very poor absorption compared to pure USP-type folic acid. (8,9,20,21,22,23) Further studies determined that the digestion of folic acid in yeast is compromised in the stomach by a protein that binds folic acid into the yeast called gamma glutamyl peptide. Gamma glutamyl peptide is not digestable in human stomachs. (21,22,25)
One study stated, “Yeast folic acid is [absorbed] only one-third as well as [USP-type folic acid].” (22) Because “gastric juice and duodenal fluid are inactive against the gamma glutamyl peptide chain of yeast folic acid digestion of yeast folic acid cannot occur in the stomach, but must take place in the jejunum in the intestine.” (20,24,25) Yeast is known as a poor source of absorbable folic acid and is stated to be “poorly representative of natural dietary folic acid.” (23) Therefore, yeast-derived folic acid would be a poor source of folic acid for pregnant mothers. However, another study stated that folic acid in other foods, in general, “…is not as available as [USP-type folic acid].” (25) Food sources of folic acid are generally about 40 percent less digestable and absorbable than pure, isolated USP-type folic acid. (9,10,11,12)
Because when I started to monitor my nutrient intake from diet and and factored in the average absorption rates for individual nutrients (unlike cronometer,) - as about 60% for folates from diet - I ended up severely deficient in quite some of them, especially folate. I remedied that by adding nutritional yeast, the only kind of food with it's exceptionally high B vitamins content which does make a huge difference with a few grams added... after all, maybe only half that much.
Considering much of nutritional science still in infancy, I'm also pretty certain that not all nutrients with beneficial health effects have even been discovered, and therefore still think the best idea to get as many (unknown) nutrients from diet as possible ..beside supplementation of the already known.
As for example with the magnesium in chlorophyll, though the magnesium in it might be much less bio-available, but then the chlorophyll has it's own health benefits.
Edited by pamojja, 04 November 2012 - 10:08 AM.