Hot Topic: GMOs

October 28, 2012

Laura, Registered Dietitian

GMOs, short for genetically modified organisms, are a hot topic!  You may have heard snippets on the news, read about Prop 37 in California in the paper, or joined a heated debate at the water cooler.  People have lots of opinions about them, and I’m here to give you some simple facts and to provide you with a basic understanding of this technology that is such a large part of our food system.

1)      GMOs are a precise and quick way to get desired characteristics in crops.  Farmers have been cross-breeding their crops to get characteristics they want in their plants (bigger, tastier, etc.) for thousands of years.  According to the World Health Organization, genetic engineering (or genetic modification) is the transfer of DNA from one species to another in a way that does not occur naturally.  DNA from plants, bacteria, and viruses are used most commonly.

2)      GMOs are everywhere!

  • Since 1994, genetically engineered food has been sold commercially in the US.
  • 9 genetically engineered crops are currently on the market in the US. The most common ones are corn and soybeans.
  • An estimated 60-70% of processed food in US is made with genetically engineered food.
  • In 2011, 400 million acres worldwide were farmed using genetically engineered seeds.  This was an 8% increase from 2010.
  • In 2011, 12 million farmers in 29 countries grew genetically engineered crops.
Crop GE % of total crop
Soybeans 87%
Corn 52%
Cotton 60%


3)      GMOs are used for a lot of reasons.  Currently in our food system, GMOs are predominately used to improve agricultural performance.  Some examples of this include the insect-resistant Bt corn and the herbicide-tolerant Round-up Ready soybean. A lot of work has been put into improving the nutritional content of crops as well.  An example of this is the vitamin A-enhanced Golden Rice.  Some people think that GMO food may help us solve hunger; others disagree.

4)      There are health concerns about GMOs.  The FDA, EPA, and USDA oversee the safety of GMOs.  A lot of research has been conducted looking at the potential problems related to allergens, toxicity, antibiotic resistance, consumption of foreign DNA, and unexpected change in nutritional content.  Currently, none of these potential health concerns has been shown to be a real problem in humans.  However, some people are still concerned and would like to see more testing.

5)      There are environmental concerns about GMOs.  These include the development of pesticide and insect-resistant weeds, the need for more pesticide use, contamination of non-GMO crops, and decreased animal and plant biodiversity.  These concerns are not completely unique to GMO crops, but there is evidence that they may be aggravated by them.

6)      GMO foods are voluntarily labeled in the US. Food producers have the option to label their products as GMO-free.  By law, USDA certified organic food cannot contain any GMO ingredients.  This can help consumers avoid GMO food if they wish.  GMO whole foods are very rare.  None of Harmons’ fresh produce is genetically engineered.

7)      On November 6th, Californians will have the opportunity to vote on whether or not they want mandatory labeling in the US.  What would you vote if you were in California?



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