You might be sure about the fruits or vegetables that you are eating since you can see them but you cannot claim the same about packaged foods which at time consists of ingredients which have been modified genetically. There are number of GM crops available in U.S and though a lot of it becomes a part of the animal feed but some of it reaches the vending machines and kitchen of people. Most of the processed food eaten by us contains genetically modified ingredients which have been derived from soybeans or corn. FDA has stated that GM crops can be safely eaten and results in no harm to human beings but some critics do not agree with FDA and state that proper research was not undertaken by FDA before coming to this conclusion. Critics believe that GM food can lead to allergic reaction and can have damaging effect on the digestive tract and the immune system. In my opinion a neutral agency should undertake a proper study so that a clearer picture can emerge.