Oh my. We have done a lot of research on this as well, since we had a daughter who had a number of food allergies and lived with incredible levels of environmental pollutants (in China for 11.5 years). I can tell you that from what I have read (and I am not full-blown Weston A Price, but love Nourishing Traditions) and from what I saw (with our daughter), much of the food we get at the supermarket is quite near the bottom of the food chain and some can be downright toxic. I don't have the time to fully explain it (I am at work), but the relationship between soil depletion, in terms of organic matter, and nutrient changes in veggies resulting therefrom, etc. (chemical fertilizers notwithstanding), even in the last 50 years, is quite interesting. I don't care for the certified organic industry, but I can see a night and day difference in the food we produce from our little farm (and we are poor farmers indeed) and what we buy in the stores. An egg from one of our pastured hens compared to a battery hen egg from Walmart is really a different thing altogether. And bacon from the hogs actually goes bad after 7 days or so in the fridge vs weeks for a 'normal' package from the store. Sorry, but I like food that rots. We eat what we grow, or buy from those who we know, for the most part, and hope we can do more of it as the years go by. None. In fact, there is significant empirical evidence to the contrary. To whit: where there is vegetarianism, there is no bacon. And everyone knows that where there is no bacon, there is no happiness.