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The Negative Side Effects of Eating Genetically Modified Foods


I'm a mother and environmental scientist with a passion for environmentalism, nutrition, gardening, and activism.

Many food additives that come from corn are genetically modified. Avoid corn-derived food additives.

Many food additives that come from corn are genetically modified. Avoid corn-derived food additives.

What Are the Side Effects of GMOs?

By the time you're done reading this article, you will be fuming. There is scientific data that shows that GMOs have dangerous side effects in animals. There is evidence, based on animal studies, that eating genetically modified foods causes a wide variety of problems, which makes tracing the source of the problem difficult, especially over time.

There isn't enough data to show the long-term effects of eating food that has been genetically altered, but some scientists predict that GMOs are one of the root causes of epidemics that now plague the United States including obesity, diabetes, asthma, fertility problems, food allergies, and even cancer. What about ADHD and autism? There are many conditions that are on the rise which coincide with the introduction of changes in our food system over time.

According to the Academy of Environmental Medicine, there should be "an immediate moratorium on genetically modified foods."

What Is Genetically Modified Food?

Confusion exists over the difference between genetically modified crops and hybrid crops. A hybrid is a cross between two plant varieties. The goal of a hybrid crop is to produce a plant that has the best features of each of the crossed varieties. This is done in controlled ways but also can happen in nature.

Genetic engineering of crops involves altering the genetic makeup of a crop in some way, typically for the purpose of making that crop perform better. DNA is extracted from animals, viruses, bacteria, insects, and even humans and then inserted into the DNA of the crop.

An example: The pesticide Bt (Bacillus thuringeiensis), a bacterium naturally occurring in soil, is inserted into corn DNA. The pesticide Bt produces a toxin that destroys the intestinal lining in insects upon eating the corn plant. Although this toxin occurs naturally, it would never become part of corn DNA without intervention.

These terms are commonly used to represent food that has been altered genetically.

  • Genetically Modified Organism (GMO)
  • Genetically Engineered (GE) Food
  • Genetically Modified (GM) Food

GMO Controversy

Supporters say GMOs will help solve world hunger by providing more efficient crops that can grow in less ideal climates or soils for example. The FDA reports that there is no evidence that GMOs are harmful to us and that these crops are held to the same safety standards as non-GMO foods. Big companies that benefit from selling GMO products, like Monsanto, oppose labeling GMOs on food products and maintain that they are perfectly safe for consumers to eat.

Those against GMOs site their own scientific research that says GMOs cause allergies, infertility, reproductive problems, organ damage, insulin regulation problems, accelerated aging, immune problems, and changes to the gastrointestinal system. Many organizations and scientists agree that there is not enough data about the long-term side effects of ingesting GMOs.

Which Foods Are Genetically Modified?

Some examples of foods that are genetically modified:

  • 93% of soybean fields in the United States are genetically modified and 77% worldwide.
  • 85% of corn in the United States is genetically modified and 26% worldwide, affecting products that contain canola oil, corn syrup, cornmeal, xanthan gum, and cornstarch.
  • 95% of sugar beet crops grown in the U.S. in 2010 were genetically engineered and 9% worldwide.
  • 93% of cotton is modified, 49% worldwide affecting cottonseed oil.
  • 80% of Hawaiian papaya is genetically altered.
  • 70–90% of processed foods on grocery store shelves contain GM foods.
  • Livestock is fed GM foods, affecting meat, milk, and eggs.

What Do Scientists Say About GMOs?

Scientists have been harassed, fired, and received death threats for publishing information or expressing opinions such as the following against GMOs.

  • Scientists speculate that the rise in infertility, low-birth-weight babies, and other reproductive ailments in the U.S. population since the mid-1990s may be linked to the introduction of genetically modified foods.
  • The American Academy of Environmental Medicine asked doctors to educate patients about the dangerous effects of eating GM foods.
  • Scientists at the FDA warned the White House in the 1990s that potential side effects of GMO foods would be difficult to detect. Instead of gathering more long-term data, the White House appointed Monsanto's former attorney to push the U.S. forward with GMOs and biotechnology. FYI: Monsanto sells approximately 90% of the genetically modified seeds used in the United States. Many of these seeds are modified to give the crops the ability to withstand heavy doses of the herbicide Roundup, also a Monsanto product.
  • Dr. Pushpa M. Bhargave, a biologist known around the world, believes that the increase in diseases and disorders that are affecting Americans today are due to GMOs. His opinions are based on a review of 600 scientific documents and journals about GMOs.
  • The global scientific community continues to express that there is not enough data to show that GMOs are safe for humans. More testing and understanding is needed. They state that we have all become guinea pigs in a huge scientific experiment.
  • Other scientists point out that because the effects of eating GMOs are not understood, new diseases are likely to develop without us knowing exactly why until too much time has passed. An example of this already occurred in the 1980s when a genetically engineered food supplement called L-tryptophan killed people and caused illness and disability because it took four years to find the cause.
  • It is reported that more and more doctors are prescribing GM-free diets.
  • The American approach to food safety is based on "substantial equivalence" whereas the European approach is based on "precautionary principle." The FDA says there isn't evidence to support that GMOs are not safe; European officials say that if a reasonable risk exists it is not worth continuing to eat GMOs. This situation is repeated with other food safety issues, like the use of food dyes.

Allergies From Genetically Modified Food

Genetically modified soy contains up to seven times more of the allergen called trypsin inhibitor than non-GM soy. It is reported that soy allergies increased 50% around the same time that genetically modified soy began being used in the UK. Many of these individuals react to skin prick tests for GM soy but don't have evidence of an allergy to the non-GM soy.

Side Effects of GMOs

Since we don't know exactly what GMOs do to our health, we have to base our decision to eat GMOs on evidence from animal studies and the opinions of experts in the scientific field. For some people, the possibility of a risk is enough to make that decision to stop eating GMOs.

See the table below for some specific findings related to GMO studies, including a human study showing that DNA from the modified food inserts itself into bacteria present in human intestines.

Studies on GMO Foods

Food SourceExperimentEffects of GMOs in Diet

Genetically modified foods

Fed to rats and salmon

Increased weight gain, ate more, changes in immune system, altered intestinal structure http://sciencenordic.com/growing-fatter-gm-diet

Genetically modified soy

Humans (the only published human study)

The gene inserted into GM soy transfers into the DNA of bacteria living in human intestines - the gene now functions within the bacteria

Genetically modified soy

Fed to mice

Embryos developed significant DNA changes

Genetically modified soy

Fed to hamsters over three generations

Third generation lost ability to have babies, high mortality of offspring, slower growth, some had hair growing inside mouths

Genetically modified soybeans or corn

Fed to mice and rats; combination of 19 studies

Significant organ disruption; livers and kidneys

Genetically engineered soy

Tested goat milk

Found the modified DNA sequences in the goats milk, having passed from the intenstines to the blood stream to the udders into the milk

Genetically engineered plants

Analyzed genes in fish

Found modified DNA in nearly all inner organs

Genetically modified soy

Fed to female rats

Most of their babies died within three weeks, babies were smaller, offspring less fertility

Genetically modified corn

Fed to mice

Fewer babies, smaller babies

Genetially modified cottonseed

Fed to buffalo in India

Premature deliveries, abortions, infertility, prolapsed uteruses

Genetically modified corn

Fed to pigs in U.S.

Became sterile, had false pregnancies, gave birth to bags of water

Genetically modified corn

Fed to cows and bulls

Became infertile

Multiple genetically altered foods

Various animals

Significant immune dysregulaton—associated with asthma, allergy and inflammation

GMOs Are High Risk

Based on this extensive list of animal studies that show severe side effects, GMOs appear to be a risky addition to the food supply. More data need to be gathered, but not at the expense of our health.

This content reflects the personal opinions of the author. It is accurate and true to the best of the author’s knowledge and should not be substituted for impartial fact or advice in legal, political, or personal matters.

© 2012 Melis Ann


JESUS on May 03, 2019:

Hello my friends

Chimobi Njoku-Amah on April 10, 2019:

This article is timely. People should be watchful of what they eat. Like the saying goes "you are what you eat".

James Clarkson on March 25, 2019:

Shauna L Bowling can you share your "studies" with us as I would be interested to read this "study" about how GMO causes deformities in babies.

David on February 28, 2019:

This is stupid scaremongering

Josiah Clark on February 25, 2019:

This article is prity good. How many scientists are against GMO? And how many are for it? Do you know? I never read an article better than this one. It has good information. I recomand this one to everyone.

Shawn Weissman from Boston, MA on June 04, 2018:

Thank you for this! The table makes it very easy to understand and it is always good to get info from both sides.

Thomas on August 23, 2017:

Citations on your chart? Find it hard to believe that when 90% of corn crops in the United States are genetically modified that cows and pigs could not create offspring after being fed GM.

Melis Ann (author) from Mom On A Health Hunt on August 11, 2017:

GMO Questioner-we should always be questioning our online sources so I think your question is valid. Jeffrey Smith is the founder of IRT as well as an author and film maker. Of course, he is one voice, but he isn't the only voice out there. Personally, I like to look at many voices from both sides of an issue and come to my own conclusions which is why I wrote this piece. I appreciate your question, take care!

GMO Questioner on August 10, 2017:

I heard that the IRT is untrustworthy as it is just one person. Can you clarify this for me please?

Shauna L Bowling from Central Florida on September 03, 2016:

Those who say GMO-based foods are harmless are full of crap. I've read the studies. We have humans who are deformed or have life-threatening diseases as the result of consuming GMO foods. I can't harp on this enough. I'm so glad you've posted this article.

I carry a list in my purse of food manufacturers that are known to use GMO seeds and foods in their products. Many of them are brands I used to buy, but no longer support. I refuse to buy their products.

I can't undo the damage that may have been done to my body before I became more educated about the foods we ingest and the products that are used in growing our food, but I can certainly make better choices moving forward.

I'm behind you all the way, Melis. Sharing and spreading the word.

Melis Ann (author) from Mom On A Health Hunt on March 19, 2015:

Mimi, I encourage you to read the many hubs I have written on the subject. Most of the concern around GMO's are the unknown effects we are yet to discover. Thanks for reading.

Mimi on January 07, 2015:

Why is GMO food bad for you?? And what it do to you?? What is a good part of GMO food?? Pls I wanna know the answer soon as you can answer it. Thank u !

ruelamoncio on March 06, 2014:

wow,,,,nice info. I've learned a lot

sometimes being innocent can made us stumbled

Melis Ann (author) from Mom On A Health Hunt on February 17, 2014:

Good for you April! If we all followed your example we would all be healthier. Maybe a study of people who eat standard food and homegrown/organic would start to show a more clear picture of the dangers of GMOs.

April Salsman on February 16, 2014:

I myself have had many issues with food, in itself. I have to think, how many people have much to say, but no action. My meaning is, if your not sure about if this is actually real, or if something needs to be tested, just try it out. For one thing, no one needs to do research to see that there is a rise in Cancer, Autism, allergies, and many more things. Back in the time there was very few who knew someone with Cancer, now almost every person alive knows someone with Cancer, or has had Cancer. I myself lost my father to this, so I have to say, "What is causing this?" What are we doing wrong, it points to something, dose it not? Yes, I agree it can be a combination, but it is also what we are doing to ourselves. Soon food will not be food, but a by-product of the real thing. I say yes to labeling, yes to more teaching and education for home grown foods, and yes to informing and educating our children about the food we consume. I myself raise my own milk, eggs, and this year enough veggies and fruits for the entire year for my family, all on 1/3 of a acre. I am proud to know my seeds are non-GMO, as well as safe, because I watched the entire process of the growth, and production of my food. Food is killing America, and it is killing our future our children.

Melis Ann (author) from Mom On A Health Hunt on November 05, 2012:

In light of the election I've shared this again with my followers. Please pass this along. Californians ~ we are counting on you to vote YES for Prop 37 to enforce labeling of genetically modified foods.

Melis Ann (author) from Mom On A Health Hunt on October 03, 2012:

When I get back in to add the latest research, I will definitely add more source data. I agree the argument is more compelling with cited research. I'm happy to have found a wide variety of studies from around the world which I summarized in tabular form above. I've been meaning to get back to this article as there are some great new studies showing the detrimental impacts of GMOs.

aa lite from London on October 03, 2012:

Your arguments would be more convincing if you provided links to the actual papers in which scientists published the studies whose conclusions you cite. It isn't really enough to write "scientists say", or even to give the name of a specific scientist.

In 1998 Andrew Wakefield published a paper claiming that the MMR vaccine caused autism. Other studies failed to reproduce his results and later investigations showed that he had a lot of undeclared conflicts of interest and that he manipulated data. Basically anybody can say "scientists say that..........." fill in your favourite argument, but that doesn't really mean much.

Ocho7 on August 21, 2012:

Thanks for replying.

Melis Ann (author) from Mom On A Health Hunt on August 21, 2012:

Good question Ocho7. I'm guessing that when you first plant they remain separate crops, but over the season would mix. It would be difficult to do a controlled experiment with them side by side as like you said they would need different treatments and care.

Ocho7 on August 21, 2012:

I have a questions in regards to video of Jeffery mentioning his friend who is a farm grew GMO corn and NON GMO Corn and the cows choose the Non GMO corn. How is it possible to plant GMO and NON GMO Corn side by side? From the research I have done, it implicates that the soil, seed and weed killer, attaches to the Non GMO and makes it GMO especially when they are so close.

Melis Ann (author) from Mom On A Health Hunt on February 24, 2012:

Someday I hope it's easier to find non-GM foods with labels! Thanks for the comment Turtlewoman.

Kim Lam from California on February 24, 2012:

This is a great article, very thorough and informative. More Americans need to learn about this scary acronym. I read labels obsessively to avoid consuming GMO-products but there are sneaky ways they can add it in our food. Considering almost every processed food contains some form of corn, they're everywhere! The best way to avoid it is to buy mostly organic foods.

Voted up and useful!

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