Jim Swayze wrote: >I like what you say, Keith, and agree with everything. But one thing is driving me nuts. While the Eades and Ray Audette may give it adequate treatment, Dr. Cordain and Ron Rosedale (whose recent book is a FANTASTIC read) underemphasize the effect of foreign proteins on our health. In practice you avoid these peptides when you strictly follow Cordain's and Rosedale's plans, but I want to hear them come out and use this as an additional reason we've so deviated from our ancestral diets. It's a powerful point as these alien protein fragments are the drivers for so many of our modern maladies. > > I think the reason is that the effect of "foreign proteins" isn't very well understood yet. The immunological defintion of a "foreign" protein is a protein that is "not self", i.e., not of one's own body. Given that definition, *all* the proteins we eat are foreign, whether they are from meat, fish, or anything else. A protein, completely digested, becomes simply a bunch of amino acids, and these are not foreign. The so-called "foreign protein" problem is that some proteins are (a) not completely digested, and (b) may enter the bloodstream in that incompletely digested form. In principle, *no* proteins should enter the bloodstream; only amino acids. There may be many reasons why this doesn't happen, some dietary, some not. For example, *some* lectins, which are *glycoproteins*, apparently cause changes in the permeability of the gut lining, allowing protein fractions to enter circulation, challenging the immune system. That's a dietary cause, but it's not clear that all and only "nonpaleo" lectins are responsible. Gut permeability may also be affected by non-dietary factors such as viral infections. Todd Moody [log in to unmask]