For millennia, ordinary people have interbred livestock and pets, sometimes with very specific objectives such as strength, size, speed, health characteristics, and so on. Farmers and casual gardeners have grown varieties of plants together and grafted plants together to produce different varieties. And, you know that the social melting pot around the world even yields human twins that look quite different as they mature. So, it appears that by analogy you do not need to be a Ph.D. geneticist to understand genetic modification of food crops.
Corporate agriculture scientists can be very precise in their genetic manipulations. Some issues with the results are not that the products are necessarily harmful, rather they are both different from the prior generation of fruits and vegetables, and more uniform in content, whether such is desirable or not. If pre-modification, a particular fruit item you regularly consumed contained 100% of Recommended Daily Allowance (RDA) of vitamin C and post-modification the percentage dropped to 16.6%, you now need to supplement your vitamin C intake if the particular produce was your only dietary source of vitamin C. Such changes occur regularly (probably not of such great magnitude) with genetic manipulation (gm). But, just as with the breeding of the livestock and pets, nobody reports “exactly” how the genetically modified offspring/produce differs from the parents/other produce.
The greatest risk is that a corporate farmer, who grows a significant percentage of some type of produce we see in the market, might use only one variety of cheaper, mass-produced, gm-seed so that we lose food quality via losing crop diversity. And, as modern clinicians are not particularly well-trained regarding dietary elements of health, the vast majority are not able to meaningfully comment on the question of potential long-term health effects of a significantly modified dietary produce.
Large corporations in every industry work to excel and to eliminate competition. However, dominance in the market by particular companies does not guarantee better products. It simply guarantees that for better or worse, we will see more of their products. Until the FDA is able and willing to more efficiently assess and report the nutritional content of foods, you should purchase as much non-modified produce as you are able. You do so to maintain healthy food biodiversity in the market. You are addressing the potential, alternative danger. If you do not buy local organic, non-modified, and similar products now, your current market decisions may result in the products being unavailable in the future. ISG Health believes you good health matters.