There are many opinions on this subject; however, data on the potential health risks of GMO foods are scanty, which has made it impractical to draw conclusions from it up till now. Nevertheless, companies that wish to release a GMO product are required to test the safety of that product. The Novel Foods and Novel Food Ingredients Regulations 1997 implement the EU Council Regulation on novel foods. This requires that before novel foods and ingredients are placed on the market, they must be assessed for safety.
Several opinions have developed along with the GMO food evolution. Some of them are in favour, claiming that there are no inherent differences between foods produced using genetically modified organisms and those using non-GMO; this is because by moving a piece of DNA from one organism into another, a "foreign" substance is not introduced.
Conversely, other opinions establish that there are too few independent (non-industry) studies of the health effects of GMO foods to have confidence in their safety. Some investigations have been carried out, but it highlights the need for more research, as well as novel methods and concepts to probe its safety.
Nowadays, all genetically engineered foods on the market fit, according to the FDA, the category of "generally regarded as safe" (GRAS).