I could spend a year or more researching this topic, or I could send you straight to the current authority on the subject... which I think is a Better Alternative. For the complete Shoppers Guide in easy to download P.D.F. Form... check out the Link Below:
Source: Center for Food Safety
Center for Food Safety Shoppers Guide (P.D.F.)
Center for Food Safety Website
I Also Refer you to their Website for more Information on the current battle against the invasion of G.M.O. or "genetically engineered" food sources in our supermarkets. These people know their stuff and are very active in trying to protect consumers, and though I am NOT affiliated with them (Though I have signed up as a member to their site and encourage others to do so...) I fully support and Endorse their on-going efforts and view them as "Fellow Combatants" who, though approach the situation differently than I do, are fighting the same Battle as I am, only from a separate front. Only when we as a people come together and do all we can to fight this ongoing Invasion into our Farms and food supply From ALL angles can we hope to secure a better future for the generations which are to follow us and who must receive this Planet from us and its food supply Once WE are gone.