Transparency's picture
The American Academy of Environmental Medicine states, "GM foods have not been properly tested" and "pose a serious health risk. ***Not a single human clinical trial on GMOs has been published***” (emphasis mine). Petri dishes and labs tests will never equate human clinical trials, as the human body is enormously complex. If few or no human clinical trials have taken place, how can the biotech industry simply “assume” GMOs are safe – basing conclusions solely on other types of testing? Isn’t the assumption of safety yet another form of broad-based correlation?

A:Expert Answer

Thank you for coming to GMO Answers! We all want to know that the food we eat is safe, including GM foods from GM seeds.


Denneal Jamison-McClung, associate director of the University of California, Davis International Biotechnology Program discusses the health and safety of GMOs in a recent post. She explains the following:


“GMO foods have a long, safe track record (17 years in the marketplace). From their introduction in 1996 until now, scientists have found, through repeated and extensive testing, that GMO foods are no more risky than comparable non-GMO foods, nor do they differ in nutritional value. 

“Currently approved GM crops developed through specific genetic additions or subtractions are as safe as conventional and organic crops developed via random genetic shuffling.  Most people do not realize that plant breeders have been randomly altering and admixing plant genomes for centuries.  Techniques using chemicals and radiation to break plant DNA and induce mutations have been used to develop many conventional and organic crops. Whether using traditional approaches or genetic engineering, the goal of plant scientists is to develop crops with new and agriculturally useful traits. Humans have been changing plant genomes for generations – we just have new, more precise, tools.” 

Dr. Bruce Chassy, professor emeritus of food safety and nutritional sciences at the University of Illinois at Urbana-Champaign, answered a question about human feeding trials. An excerpt of his insight to the question is below, and the full response is available here:


“The composition of GM crops and foods derived from them is carefully studied. Using our knowledge of toxicology, food allergy, and nutrition, it is possible to predict if a food will have an adverse effect based on composition alone. The study of composition is a better indicator of safety than are animal studies on whole foods. Many scientists in fact question if whole food studies in animals are useful and have suggested they not been done. Studies in humans are even more difficult to do and would likely yield little useful information since the diets' composition is the same, the outcome would be the same. Since these are whole foods, with animal studies animals can be fed diets containing large amounts of the food ingredient being tested every day, which would be very difficult to do with humans. Moreover, at the end of a study with animals, post-mortem examinations are performed that allow for a careful pathological examination of most all tissues to understand the pathologies that resulted from consuming large amounts of the whole food tested.”


You might also be interested in the post “Environmental Medicine – Not Your Average Specialty” on Science-Based Medicine. Here is an excerpt:


“The AAEM is not recognized by the American Board of Medical Specialties. It is listed as a questionable organization on Quackwatch. And the American Board of Environmental Medicine is listed as a dubious certifying board.

“…Environmental medicine patients are told that the world has made them sick. They blame their symptoms on everything from cell phones to the very walls of their houses, from air pollution to food additives. The theory is that while one chemical might not be a problem, many different chemicals and substances overwhelm their ability to cope.


“Environmental Medicine involves the adverse reactions experienced by an individual on exposure to an environmental excitant. Excitants to which individual susceptibility exists are found in air, food, water, and drugs, and are frequently found in the home, work, school, and play environments. Exposures to these agents may adversely affect one or more organ system and this effect is commonly not recognized by individuals and their physicians.

“Their practice guidelines are explained here. Many of the diagnostic tests they recommend are questionable. Treatment includes avoidance, immunotherapy, nutritional supplements, detoxification, restricted diets, and drugs.”


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Joseph Najjar's picture

If you want to be realistic about it, they have been tested extensively....we have all been eating them for nearly two decades within the commercial market. The studies that have been run give no reason to consider them a " serious health risk" Here is a comprehensive look at GMO safety, along with many other issues with them:

CactusWest's picture

Safety (health) studies 10-15 year duration (in advance of 1994 FDA/USDA approval)?

Community Manager's picture

Hi, you might be interested in this response to another long-term health/safety question provided by Dr. Bruce Chassy, professor emeritus of food safety and nutritional sciences at the University of Illinois at Urbana-Champaign:

Alex Rauber's picture

AAEM obviously failed to manage to read the wikipedia page of gm food controversies about the complication of human testing, gm foods are foods, so we would test them like food, human clinical trials are not done on foods they are done on drugs.

Human studies and obstacles[edit]
While some groups and individuals have called for more human testing of genetically modified food,[155] there are several obstacles to such studies. The General Accounting Office (in a review of FDA procedures requested by Congress) and a working group of the Food and Agrigultural and World Health organizations have said that long-term studies of the effect of genetically modified food on humans are not feasible. The reasons given have included the problem that there is no plausible hypothesis to test, that very little is known about the potential long-term effects of any foods, that identification of such effects is further confounded by the great variability in the way people react to foods and that epidemiological studies are not likely to differentiate the health effects of modified foods from the many undesirable effects of conventional foods.[156][157]
Additionally, there are strong ethics that guide the conduct of research on human subjects, which mandate that the intervention being tested must have a potential benefit for the human subjects, such as treatment for a disease or nutritional benefit (ruling out toxicity testing on humans).[158] In this context, scientists and regulators discussing clinical studies of genetically modified food have written that the "ethical and technical constraints of conducting human trials, and the necessity of doing so, is a subject that requires considerable attention."[159] Golden rice has been tested in humans to see if the rice provides a nutritional benefit, namely, increased levels of Vitamin A.[160][161][162]