Just the facts. From the experts.


As we receive more views on our five-part video series on genetically modified foods, we continue to receive great questions about safety, testing, health effects, etc. Here are a few more.


YouTube commenter "VoluptuousB" asked: "Resisting drought, climate change and insects, how on earth can you be sure that that particular gene will not have an adverse effect on my digestion and body functions in the long run?! I'm still skeptical about this."

  Dr. Ruth MacDonald, Chair of the Department of Food Science and Human Nutrition and professor at Iowa State University responded: "The question is asking how we can be sure a gene used to address drought, climate change and pests won’t harm the human body in the long term. The answer to this question lies in the type of genetic modifications that are being used in crops.

"A gene is the ‘secret code’ that tells a cell how to make a specific protein. The gene doesn’t do anything except spell out how to put amino acids in order to create the desired protein. That is the way all genes in all living things work. The protein that is made by the plant, based on the code provided by the gene, is that ‘action’ component that allows the plant to resist a pest or to use a different metabolic pathway. The gene and the protein used in GMOs are not active in people. They don’t target any human function – they only target pests or actions in the plant itself. So when you eat a GMO the gene and the protein are broken down just like all the other genes and proteins that come from that same plant (all living things have lots of genes and proteins naturally – a GMO is only one tiny fraction of the entire gene pool in that plant).

"Before any GMO product is allowed to enter the food system, it must be clearly proven to not have any effect on human health. GMOs have been more thoroughly tested than any other food item ever. There has never been any evidence that GMO foods or ingredients made from GMO crops have any negative health effects – and people have been consuming GMO foods for over a decade. The GMO genes are not incorporated into the human body (remember all living things have genes – even non-GMO foods like carrots have a lot of genes!), and the proteins (all foods have many proteins too!) are broken down into those amino acids and are used just like any other protein.

"So the answer is that GMOs have been tested, they have been approved by the US government, all of the major health-related scientific foundations consider them to be safe, and there is a long record of safe use with no evidence of harm to human health."


Best Food Facts reader "Carlos" contacted us directly through the website and asked: "How, exactly, does the FDA review and approve a new GM crop/food?"

  Dr. Denneal Jamison-McClung, Associate Director of the Biotechnology Program, University of California, Davis, responded: "Regulatory oversight of agricultural biotechnology is shared by the USDA, FDA and EPA. The FDA’s primary role is to ensure that biotech crops are safe to eat and chemically/nutritionally equivalent to the parental crop variety.

"These three federal agencies follow the 1986 Coordinated Framework for Regulation of Biotechnology (US Federal Register, June 26, 1986, 51 FR 23302).  The Framework includes a number of laws and regulations, including the Federal Food, Drug and Cosmetic Act (FFDCA), which applies most directly to the FDA’s role in regulating biotech crops (http://usbiotechreg.epa.gov/usbiotechreg/lawsregsguidance.html)

"The FDA works with companies developing biotech crops through a consultation process that begins in the early stages of crop improvement and proceeds through final approval (10-15 years).  Each new biotech crop is evaluated on a case-by-case basis, depending on the new trait or traits that have been incorporated. Policies and procedures are outlined on the FDA website: http://www.fda.gov/Food/Biotechnology/default.htm.

"Information that must be provided to the FDA regulators (Biotechnology Evaluation Team: a consumer safety officer, a molecular biologist, a chemist an environmental scientist, a toxicologist and a nutritionist) prior to biotech crop approval will include (list is a direct quote from FDA website):

    1. The name of the bioengineered food and the crop from which it is derived.
    2. A description of the various applications or uses of the bioengineered food, including animal feed uses.
    3. Information concerning the sources, identities, and functions of introduced genetic material.
    4. Information on the purpose or intended technical effect of the modification, and its expected effect on the composition or characteristic properties of the food or feed.
    5. Information concerning the identity and function of expression products encoded by the introduced genetic material, including an estimate of the concentration of any expression product in the bioengineered crop or food derived thereof.
    6. Information regarding any known or suspected allergenicity and toxicity of expression products and the basis for concluding that foods containing the expression products can be safely consumed.
    7. Information comparing the composition or characteristics of the bioengineered food to that of food derived from the parental variety or other commonly consumed varieties with special emphasis on important nutrients, and toxicants that occur naturally in the food.
    8. A discussion of the available information that addresses whether the potential for the bioengineered food to induce an allergic response has been altered by the genetic modification.
    9. Any other information relevant to the safety and nutritional assessment of the bioengineered food."


 Best Food Facts reader "Carlos" continued... "You say GMOs are 'Safe for people to eat.' What human safety testing is done?"

Dr. Denneal Jamison-McClung, replied, "Before researchers begin to develop a biotech crop, a lot of thought is given to the potential safety of an added trait, including the nutritional profile, potential toxicity and/or allergenicity, etc… of any protein that would be added to the crop being studied.  Only traits (proteins) that are reasonably evaluated to be safe will be added to the crop through genetic engineering, which is a more specific and controlled way to move genetic material than traditional plant breeding methods.  Once a biotech crop is developed, it is compared to the parental variety from which it was derived to check for similarity in chemical and nutritional content, physiology, growth characteristics in the lab, in the greenhouse and in the field.  It must be found to be “substantially equivalent” to the parental variety in order to be approved for use.  Animal feeding studies to confirm the safety profile results are performed, but human safety testing is not part of the approval process. 

"Since 1996, biotech crops have been part of the human food supply with no documented health impacts and no conceivable scientific reason to believe that they are nutritionally different from conventional crops." 


What additional questions do you have about genetically modified foods? 

View our five-part video series focused on genetically modified food: 

GMO 101 

Are GMOs Safe?

Are GMOs Harmful to the Environment?

Are GM Foods Nutritionally Different? 

GM Labeling

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