QHow can you be sure that GMO foods won't affect human health long-term?

How can you be sure that GMO foods won't affect human health long-term?

AExpert Answer

GM 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 GM foods are no more risky than comparable non-GM 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 scientists use traditional approaches or genetic engineering, their goal 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. 


Regulatory and food-safety focus should be on the resulting trait(s), not on the specific modification or plant breeding process by which the genetic changes were made. Because they have different traits, GM foods are carefully evaluated on a case-by-case basis. For example, Arctic apples are non-browning GM fruits that have been developed by “turning off” a gene, rather than by adding any genes to the apple genome. Whether a trait occurs naturally, is chemically or radiation induced or is purposely incorporated via genetic engineering, inherent risks are the same. 


Given that we’ve been genetically modifying plants for millennia, using one approach or another, we should frame this question in terms of relative risks: How “sure” can we expect to be when it comes to long-term health impacts of GMO foods?  As with most things in life (except death and taxes, as the saying goes), 100 percent certainty is not possible or reasonable to require. However, safe use of GM foods since 1996, coupled with our knowledge of human and plant physiology, points to long-term safe use of genetic engineering as a plant breeding tool set in agriculture.

Posted on March 28, 2017
Thanks for the question, which I will address in two ways here.   1. What are three ways that organisms are modified by scientists? Here I will focus only on plants.   a. Agrobacterium: Agrobacterium tumefaciens (Agro) is a naturally occurring soil organism that causes a disease in plants called crown gall disease. In the late 1970s, Mary-Dell Chilton discovered that Agro actually transfers genes (DNA) from the Agro to the plant cell, where it becomes integrated into the plant... Read More
Posted on March 2, 2017
First of all, to clarify – hybridization is part of conventional breeding and conventional breeding uses hybridization to create new combinations of genes from parent varieties. For example, a disease-resistant wheat variety may be hybridized to a variety that makes flour better suited for making whole wheat bread. This is a common goal of most conventional breeding programs. It typically involves taking pollen from one parent and using it to fertilize another parent. The... Read More
Posted on December 1, 2016
Viroids are very small pieces of circular RNA that have the potential of causing plant diseases. These entities are infectious agents that are different from viruses because they have no protein coat encircling their genetic material. Thus far, viroids are only known to be effective infectious agents in plants. Viroids have not been associated with any animal disease, and they have not been found in animal cells and tissues.    Biotechnological tools are being used in... Read More