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The Real Risks of GMO Foods & How to Avoid Them
May 1, 2023
Next time you’re at the grocery store, think about this: It’s estimated that more than 75 percent of the processed food lining the shelves consists of genetically engineered ingredients, and this is just one of the many scary facts about GMO foods (aka bioengineered food).
You may remember the days when GMOs weren’t even a topic on anyone’s radar. When did these “frankenfoods” get created? In the U.S. circa 1994, a genetically modified tomato known as the Flavr Savr (created by a California-based company called Calgene) became the first commercially grown genetically engineered food to be approved for human consumption.
Fast-forward to current times, and the list of what is being genetically modified is growing longer and wider with even GMO salmon getting the thumbs up for animal genetic modification.
What about crops? Well, that’s just through the roof for some: 92 percent of corn, 94 percent of soybeans and 96 percent of cotton produced in the U.S. were genetically modified strains as of 2020.
Are GMO foods safe? According to the Institute of Science in Society, “It is clear that genetic modification is inherently hazardous, as it invariably result in unpredictable and uncontrollable changes in the genome and the epigenome (pattern of gene expression) that impact on safety.”
Some people say there are GMO foods pros and cons, but I think you may agree that the dangers or cons far outweigh the potential so-called “benefits.”
What Are GMO Foods?
What does GMO stand for? A GMO is a genetically modified organism. These living organisms contain genetic material that has been artificially manipulated in a laboratory through genetic engineering.
Foods that use genetically modified organisms (GMOs) are referred to as genetically modified foods (GM/GMO foods), genetically engineered foods (GE foods) and more recently bioengineered foods (BE foods). Genetic modification of living organisms produces combinations of animal, plant, bacteria and virus genes that do not normally occur in nature or through traditional crossbreeding methods.
Do you want to know one of the main reasons why companies are fans of genetic engineering food? It results in higher crop yields.
According to a 2018 article published in the New York Times, “Yields of corn, cotton and soybeans are said to have risen by 20 percent to 30 percent through the use of genetic engineering.”
What is GMO food? It’s food produced with genetic engineering.
The use of “partially produced with genetic engineering” on food labels is the result of a 2016 federal law that mandated uniform labeling of all food products containing genetically engineered ingredients.
When Bill 764 was signed into law in 2016, it created an entirely different and controversial standard in the U.S. for labeling GMOs. It also replaced previous state laws like Vermont’s that were especially tough on GMOs. Many people in both the pro-GMO and anti-GMO sector were unhappy with the way in that GMO food content can currently be indicated on a food label.
Some companies are unhappy with the costly efforts of having to go through the necessary processes to carry a non-GMO label even if they are not producing a genetically modified food. Other manufacturers choose not to mention that they’re creating GMO products while others may direct consumers to an external source (such as a website) for additional information about the GMO status of the product.
In general, it can be very hard to know if a product isn’t GMO if it’s not organic and certified non-GMO.
This helped lead to a change that took effect in 2022, in which the term GMO food was replaced with bioengineered food. Called the “National Bioengineered Food Disclosure Standard,” the new law is regulated on a federal level with the goal to provide more information to people on the foods they eat and help lead to standardization of food labeling for BE food.
The updated law does provide a bit more transparency for consumers, including the option for QR codes to scan to get more information about the food someone is buying, but there are also many exceptions that don’t require the BE labeling. In short, the labeling standards are slightly improving but still far from perfect.
What is a GMO food list? Here are the leading examples of GMO foods you may be consuming and don’t even know it!
- Sugar Beets (a top source for refined sugar)
- Cotton (think consumable cottonseed oil)
- Papaya (GMO papaya is grown in Hawaii or China)
- Summer Squash/Zucchini
- Animal Products (conventional meats and dairy)
- Microbes and Enzymes (cooking and process agents that are hard to track because they’re often not even listed on food labels )
This is only a partial GMO foods list.
Other common food ingredients that are often GMO include:
- Vegetable oil, vegetable fat and margarines that are made with soy, corn, cottonseed and/or canola oil
- Ingredients that come from soybeans, including soy flour, soy protein, soy isolates, soy isoflavones, soy lecithin, vegetable proteins, tofu, tamari, tempeh and soy protein supplements.
- Ingredients derived from corn like corn flour, corn gluten, corn masa, cornstarch, corn syrup, corn meal and high fructose corn syrup.
The Non-GMO Project
The Non-GMO Project was created “to give consumers the informed choice they deserve.”
According to the the Non-GMO Project, it aims to provide consumers with “the most accurate, up-to-date standards for non-GMO verification.” It says that in order for a product to be Non-GMO Project Verified, its inputs must be evaluated for compliance with its standard, which categorizes foods into the following risk levels: high, low, non and monitored.
The Non-GMO Project uses a third-party technical administrator to evaluate a food item and determine whether or not it meets the Non-GMO Project’s Standard for GMO avoidance.
What is a non-GMO food? Generally speaking, a non-GMO food is one that has not been genetically modified. The Non-GMO Project seal is a way for consumers to know that a food item has passed its guidelines and is a verified non-GMO product.
Looking for a way to navigate your local grocery store and steer clear of GMOs? Check out this Non-GMO Project Shopping Guide, which helps you identify non-GMO foods by food category and is a helpful tool when you go food shopping.
Major Risks of GMOs
Why are GMOs bad? Since they are still relatively new to human consumption, GMO foods dangers are still continuing to be discovered, but let’s take a look at the some of the possible GMO foods health risks we know about so far.
According to the Center for Food Safety, these are some of the main human health concerns at this time.
1. Allergic Reactions
How can GMOs possibly increase allergies? When an organism is genetically modified by humans, this changes the expression level of natural components of that organism, which may make allergies worse.
A scientific review published in 2016 in the journal Food Science and Human Wellness provides a perfect illustration of this scenario:
One example is the production of soybeans enriched in the amino acid methionine. The enhanced synthesis of this amino acid is the result of a gene isolated from Brazil nuts. As a consequence, some consumers allergenically sensitized to these nuts have allergic reactions to the transgenic soybean.
Talk about playing with nature!
Another scientific review titled “Genetically modified foods: safety, risks and public concerns—a review” points out that new proteins can be synthesized during genetic modification that can produce “unpredictable allergenic effects.” An example of this phenomenon is when bean plants that were genetically modified to increase cysteine and methionine content had to be discarded when it was realized that the expressed protein of the transgene was highly allergenic.
Another source of allergic reactions and other concerning side effects occurred in 2003 when about 100 people who lived next to a Bt corn field developed a number of concerning symptoms, including respiratory, skin and intestinal reactions from breathing in the Bt corn pollen. Blood tests from 39 of the victims exhibited an antibody response to Bt-toxin.
Furthermore, these same unwanted symptoms showed up in 2004 in at least four additional villages that planted the same variety of GM corn. Some villagers also credited the corn to several animal deaths.
2. Antibiotic Resistance
It’s frightening yet true that before GMOs are released for public consumption, there are no human clinical trials! A review published in 2009 titled, “Health Risks of Genetically Modified Foods,” talks about how one of the fears with GM crops revolves around the use of antibiotic resistant genes as markers in GM crops.
The concern is that these antibiotic resistant genes could be transferred to human gut bacteria and decrease the effectiveness of antimicrobial therapy and hence increase antibiotic resistance.
In November 2012, the Journal of Food and Chemical Toxicology published a paper titled “Long Term Toxicity of Roundup Herbicide and a Roundup-Tolerant genetically modified maize.” This study received a lot of attention worldwide and for good reason — it was the first study to look at the possible effects of a GMO corn diet treated with Monsanto’s Roundup herbicide under controlled conditions.
Somewhat strangely, the journal later retracted the article because “Ultimately, the results presented (while not incorrect) are inconclusive, and therefore do not reach the threshold of publication for Food and Chemical Toxicology.”
However, this research study ended up being republished in 2014 by Environmental Sciences Europe, and it reveals that rats fed for two years with Monsanto’s glyphosate-resistant NK603 corn developed a lot more tumors and died earlier than controls. It also found that the rats developed tumors when glyphosate (Roundup), the herbicide used with GM corn, was added to their drinking water.
Female subjects developed large mammary tumors more frequently and before the control group. Meanwhile, males experienced four times more large palpable tumors starting 600 days earlier than in the control group, in which only one tumor was noted.
According to the study, the tumors were both cancerous and non-cancerous. The non-cancerous tumors were nearly as concerning or potentially devastating to health since they could cause the animals internal hemorrhaging, compression and obstruction of function of vital organs, as well as the release of harmful toxins.
4. Loss of Nutrition
According to Jonathan R. Latham, Ph.D., a plant biologist and the co-founder and executive director of the Bioscience Resource Project, who has conducted GMO research during the course of his career, “I now believe, as a much more experienced scientist, that GMO crops still run far ahead of our understanding of their risks.”
Genetically modified crops often have altered nutritional profiles. Some research reports increased levels of antinutrient compounds and lower levels of desirable nutrients in certain GMO crops compared to conventional crops.
Jeffrey M. Smith, MBA, director of the Institute for Responsible Technology (IRT), points out how “the disruptive and unpredictable nature of the process of genetic modification itself” may introduce or elevate allergens, toxins and antinutrients in GM foods.
The Center for Food Safety sums up this concern so well:
Genetically engineered foods are inherently unstable. Each insertion of a novel gene, and the accompanying “cassette” of promoters, antibiotic marker systems and vectors, is random. GE food producers simply do not know where their genetic “cassette” is being inserted in the food, nor do they know enough about the genetic/chemical makeup of foods to establish a “safe” place for such insertions. As a result, each gene insertion into a food amounts to playing food safety “roulette,” with the companies hoping that the new genetic material does not destabilize a safe food and make it hazardous. Each genetic insertion creates the added possibility that formerly nontoxic elements in the food could become toxic.
Potential Risks of GMOs Based on Animal Research
The IRT also put together a list of observed effects of GMOs on animals:
- Rats that were fed potatoes engineered to produce their own insecticide developed potentially precancerous cell growth in the digestive tract; inhibited development of their brains, livers and testicles; partial atrophy of the liver; enlarged pancreases and intestines; and immune system damage.
- Seven out of 20 rats fed the GM Flavr Savr tomato for 28 days developed stomach lesions (bleeding stomachs); another seven of 40 died within two weeks and were replaced in the study.
- Rats fed Monsanto’s Mon 863 Bt corn for 90 days showed significant changes in their blood cells, livers and kidneys.
- Mice fed GM Bt potatoes experienced intestinal damage.
- A quarter of sheep died after grazing in GM Bt cotton fields for a week.
- Over 20 farmers in North America report pigs and cows became sterile from GM corn.
- Twelve dairy cows died on a farm in Germany after being fed a diet with significant amounts of a single GM corn variety, Bt 176.
- The liver cells of mice fed Roundup Ready soybeans showed significant changes.
- Mice fed Roundup Ready soy had unexplained changes in testicular cells.
- Rabbits fed GM soy for about 40 days showed significant differences in the amounts of certain enzymes in their kidneys, hearts and livers.
- Rats fed Roundup Ready canola had heavier livers.
- GM peas generated an allergic-type inflammatory response in mice.
- In farmer-run tests, cows and pigs repeatedly passed up GM corn.
1. Buy Certified Organic
The best way to avoid GMOs is to purchase certified organic products because they are not permitted to contain genetically engineered ingredients. Products can be 100 percent organic, or they can be “made with organic ingredients.”
Items “made with organic ingredients” must contain at least 70 percent organic ingredients, but 100 percent of those ingredients still must be non-GMO.
According to the U.S. Department of Agriculture (USDA):
The use of genetic engineering, or genetically modified organisms (GMOs), is prohibited in organic products. This means an organic farmer can’t plant GMO seeds, an organic cow can’t eat GMO alfalfa or corn, and an organic soup producer can’t use any GMO ingredients. To meet the USDA organic regulations, farmers and processors must show they aren’t using GMOs and that they are protecting their products from contact with prohibited substances, such as GMOs, from farm to table.
Unless it’s certified organic, beware of any food with canola, corn and soy in its ingredient list — as it’s more than likely that it contains GMOs and the effects of glyphosate.
2. Choose Items with Certified Non-GMO Labels
If a company is not selling a truly organic, non-GMO product, it’s really up to that company how much it tells you. Some manufacturers can label their entire products as non-GMO, or they can specify that a certain ingredient (usually one that is known for being GMO like corn syrup) is non-GMO.
I recommend looking for labeling like the Non-GMO Project seal on packaging to ensure that the product you are purchasing is Non-GMO Project Verified and third-party reviewed to ensure its GMO-free status.
3. Shop Local
Shopping at small local farms can also help reduce your likelihood of buying and consuming GMOs. Ideally a farm will be certified organic, but since this is an expensive certification, sometimes you may find that a local farm doesn’t carry that title yet is clearly practicing healthy farming techniques and not growing GMO crops.
Talk to the farmers at your local farmers markets, visit the farms yourself and get to know the non-GMO options in your own backyard.
4. Read Labels Carefully
If you’re not able to purchase organic foods for one reason or another, refer back to my the top GMO list, which can help you avoid some of the most common GMOs.
You’ll also want to read labels carefully, especially on items like snack foods, to avoid common genetically engineered ingredients.
The Center for Food Safety has a very helpful list of the most common genetically engineered “Big Five” ingredients commonly found in processed foods:
- Corn: Corn flour, meal, oil, starch, gluten and syrup. Sweeteners such as fructose, dextrose and glucose.
- Beet Sugar: Sugar not specified as 100 percent cane sugar is likely from GE sugar beets.
- Soy: Soy flour, lecithin, protein, isolate and isoflavone. Also vegetable oil and vegetable protein when they are soy derived.
- Canola: Canola oil (also called rapeseed oil)
- Cotton: Cottonseed oil
Another very helpful resource: the Center for Food Safety’s Shoppers Guide to Avoiding GE Food.
- What is the meaning of GMO? GMO is a genetically modified organism. Most of the time this refers to a food, but it can also be a microbe or enzyme used in food production.
- What is non-GMO? If a food carries a Non-GMO Project seal, then it has been evaluated by a third-party technical administrator and meets the Non-GMO Project’s Standard for GMO avoidance.
- Why is GMO bad? Human experience and animal studies are pointing to a scary and wide range of health concerns when it comes to GMOs, including allergic reactions, antibiotic resistance, cancer, nutrition loss and toxicity.
- GMO crops and GMO ingredients continue to be created and found in commonly consumed foods, yet no human trials have to take place first to prove the safety of this genetic engineering.
- Doesn’t it just make sense that foods in their natural state would be the safest and healthiest for our bodies? I recommend buying organic products as much as possible and looking for non-GMO labeling to protect your health and the health of your family.