Glyphosate and GMOs Are Damaging Our Health. It's Time to Ban Them

The Scientific Evidence That Justifies Banning GMOs and Glyphosate

There are an enormous number of published scientific studies showing that GMOs and their associated pesticides are responsible for multiple serious health problems for people, animals, and the wider environment.

The widespread adoption of GMO crops in the U.S. has resulted in a massive increase in the application of glyphosate, the active ingredient in Roundup, as the primary method of weed control. [1]

A landmark study on glyphosate by Panzacchi et al. was published on June 10, 2025, examining total lifetime exposure to the so-called ‘safe’ levels to which most people are subjected [2].

The study found that the lowest dose of 0.5 mg/kg, which is four times lower than the US Environmental Protection Agency’s (EPA) proposed ‘safe’ level, led to increased rates of both benign and malignant tumors at various anatomical sites compared to the controls. These tumors included leukemia, skin, liver, thyroid, nervous system, ovary, mammary gland, adrenal glands, kidney, urinary bladder, bone, endocrine system, pancreas, uterus, and spleen. [2,3]

This study confirms evidence from earlier research, including that by the IARC and Seralini et al., among many others[4,5]. It also validates the accuracy of “Genetically engineered crops, glyphosate and the deterioration of health in the United States of America,” where Dr. Nancy Swanson, our co-authors, and I demonstrated how glyphosate and GMOs are linked to over 20 chronic diseases in the U.S [1].

The First Credible Peer-reviewed Lifetime Study of GMOs and Roundup

Until Panzacchi et al. was published, there was only one credible, independent, non- industry funded, peer-reviewed lifetime feeding study of GMOs and Roundup. It found that mammary and other tumors, liver and kidney damage result from regular exposure to minute amounts of Roundup and/or a diet containing GMO corn, similar to the typical exposures people get from food. [5]

The image above shows a rat with large mammary tumors caused by consuming glyphosate at the usual levels found in food. The tumors on the right-hand side, starting from the top, are caused by eating GMO corn, GMO corn treated with Roundup, or just Roundup. (Seralini et al.)

All female rats in the study that were fed GMOs and/or Roundup (Treated Group) developed mammary tumors and died earlier than the rats fed non-GMO food without Roundup (Control Group), except for one rat that died early from an ovarian tumor. This finding aligns with Thongprakaisang et al., showing that glyphosate promotes the growth of human breast cancer cells via estrogen receptors. [6]

Treated males presented four times the number of tumors that were large enough to be felt by hand than the controls, and these occurred up to six hundred days earlier.

The International Agency for Research on Cancer (IARC)

The International Agency for Research on Cancer (IARC) has assigned glyphosate a rating of Group 2A for Cancer, the second-highest classification. [4]

This means it causes cancer in animals and has some evidence of causing cancer in humans, most notably non-Hodgkin lymphoma.

A study by Flower et al. examined the levels of cancer in children whose parents used glyphosate for weed control. They found that these children had increased levels of all childhood cancers, including all lymphomas, such as non-Hodgkin lymphoma.[7]

A case-controlled study by Swedish scientists Lennart Hardell and Mikael Eriksson also linked non-Hodgkin lymphoma to exposure to various pesticides and herbicides, including glyphosate. [8] The link between glyphosate and non-Hodgkin lymphoma has resulted in significant court cases, most of which Bayer-Monsanto has lost and awarded millions of dollars to the victims.

Genetically engineered crops, glyphosate, and the deterioration of health in the United States of America
Dr. Nancy Swanson, myself, and co-authors Jon Abrahamson and Bradley Wallet published a peer-reviewed paper, “Genetically engineered crops, glyphosate, and the deterioration of health in the United States of America,” showing how glyphosate and GMOs are linked to over 20 diseases in the U.S. The study searched US government databases for genetically engineered crop data, glyphosate application data, and disease epidemiological data. This was correlated with numerous diseases linked to the increased use of glyphosate and GMOs. A standard accepted statistical analysis showed that the odds of glyphosate and GMOs not being the cause of these diseases was 10,000 to 1. On top of these, numerous studies are confirming the link between GMOs and glyphosate with these diseases. [1]

We compiled this data into graphs demonstrating the rise in diseases, glyphosate, and GMOs. We also included green trend lines to illustrate that these increases are linked to the growing use of genetically engineered (GE) corn and soy, along with glyphosate.

Correlations with Cancer
We found strong correlations for cancers of the liver, kidney, thyroid, and pancreas, as well as deaths from acute myeloid leukemia. These correlations have now been confirmed by Panzacchi et al., who demonstrated that small levels of glyphosate and glyphosate herbicides cause these issues in rats.

Thyroid cancer, in particular, appears to be linked to the introduction of GE crops and the use of glyphosate. It seems to affect women more, while men are more susceptible to liver and kidney cancers.

Autism and Dementia
Autism and dementia have reached epidemic levels in the U.S. The chart below clearly indicates the connection between the sharp increase in glyphosate and GMOs since the 1990s and the rise in these diseases.

Researchers have shown how exposure to minute amounts of glyphosate damages the normal development of nerves.

The image above shows how glyphosate harms nerve development. The cells exposed to glyphosate had shorter, unbranched axons (the long ‘arms’ of the nerve) and less complex dendritic arbors (the smaller ‘fingers’ extending from the cell body). It is clear from the image that the glyphosate-exposed cells do not develop properly and, therefore, cannot function effectively. [9]

The scientists identified how glyphosate impacts nerve development and stated that it cannot be reversed. The main concern is that the brain, the largest network of nerves in the human body, is still developing in unborn, newborn, and growing children. Exposure to small amounts of glyphosate in food can negatively affect the brain’s normal development, leading to major issues seen in children, such as autism spectrum disorder, bipolar spectrum disorder, ADHD, and other developmental and behavioral problems.

Adult brains are constantly renewing brain cells. These nerve cells are also adversely affected by glyphosate. The graph above shows a very strong link between the increase in glyphosate and deaths from dementia.

Endocrine Disruption – Disruption to Hormones
Gasnier et al. reported endocrine-disrupting actions of glyphosate at 0.5 ppm. According to the authors, this is “800 times lower than the level authorized in some food or feed (400 ppm, USEPA, 1998).” [10]

Professor Séralini’s study published in Environmental Sciences Europe found that both GM maize and Roundup act as endocrine disruptors, and their consumption led to female rats dying—at a rate two to three times higher than the control animals.

The pituitary gland was the second most affected organ, and the sex hormone balance was altered in females fed with the GMO and Roundup treatments. [4]

Disruption of Metabolic Pathways
One of the most important studies was published by Samsel and Seneff in the peer- reviewed scientific journal Entropy in 2013. This detailed review, titled “Glyphosate’s Suppression of Cytochrome P450 Enzymes and Amino Acid Biosynthesis by the Gut Microbiome: Pathways to Modern Diseases,” demonstrated how glyphosate disrupted many biochemical pathways in the human body, including those of gut microorganisms, which could potentially lead to various diseases. [11]

Studies show that disruptions of the normal hormone and metabolic pathways are major causes of obesity, in that they disrupt the normal control mechanisms that stop overeating. Science clearly shows that glyphosate is one of these chemicals.

Diabetes
The rise in diabetes is directly connected to obesity. Most obese people develop diabetes because they overload the hormonal systems that control blood sugar. Over time, these systems begin to fail, leading to dangerous spikes in blood sugar.

Disruption of the Gut Microbiome

Samsel and Seneff’s paper identified how glyphosate disrupted the gut microbiome, causing the suppression of biosynthesis of cytochrome P450 enzymes and key amino acids. In a later paper, “Glyphosate, Pathways to Modern Diseases II: Celiac Sprue and Gluten Intolerance,” Samsel and Seneff showed that the current increase in celiac disease and gluten intolerance in people was linked to glyphosate’s adverse effects on the gut microbiome. They highlighted that glyphosate is patented as a biocide, and consequently, it kills the beneficial gut bacteria, leading to a rise in intestinal diseases. [12]

Krüger et al. showed that glyphosate affects the microbiome of horses and cows. Shehata et al. found the same effects in poultry; the researchers state, “Highly pathogenic bacteria such as Salmonella Entritidis, Salmonella Gallinarum, Salmonella Typhimurium, Clostridium perfringens and Clostridium botulinum are highly resistant to glyphosate. However, most of beneficial bacteria as Enterococcus faecalis, Enterococcus faecium, Bacillus badius, Bifidobacterium adolescentis and Lactobacillus spp. were found to be moderate to highly susceptible.” Both groups of researchers postulated that glyphosate is associated with the increase in botulism- mediated diseases in these domestic farm animals. [13,14]

Inflammatory bowel diseases are rising along with deaths from intestinal infections. Glyphosate’s disruption of the gut microbiome must be seen as a significant cause.

Kidney and Liver Disease
Kidney and liver diseases are major chronic diseases. The graph below clearly shows the relationship between GMOs, glyphosate, and the rapid increase in deaths from kidney disease in the U.S. Deaths from kidney disease fell until the widespread increase of glyphosate and GMOs.

In the lifetime feeding study of rats conducted by Séralini et al. the treated males displayed liver congestions and necrosis at rates 2.5 to 5.5 times higher than the controls, as well as marked and severe kidney nephropathies (kidney damage) at rates generally 1.3 to 2.3 greater than the controls.[5]

The image above shows kidneys and livers that have been damaged by Roundup (glyphosate), GMO corn, and both. In a later published study designed to understand why Roundup and glyphosate-based herbicides caused kidney and liver damage in rats, scientists discovered that ultra-low doses of these herbicides disrupted numerous genes’ functions, resulting in changes consistent with multiple kidney and liver disease problems.

The researchers stated, “Our results suggest that chronic exposure to a GBH (glyphosate-based herbicides) in an established laboratory animal toxicity model system at an ultra-low, environmental dose can result in liver and kidney damage with potential significant health implications for animal and human populations.” [15]

Conclusion
Research shows that GMOs and glyphosate cause multiple serious chronic diseases. Over 50 years of regulation since glyphosate’s introduction in 1974 clearly highlight regulatory failure. Authorities should fulfill their duty to protect the public by banning these substances.

References

1. Nancy L. Swanson, Andre Leu, Jon Abrahamson, and Bradley Wallet, Genetically engineered crops, glyphosate and the deterioration of health in the United States of America, Journal of Organic Systems, 9(2), 2014

2. Panzacchi, S., Tibaldi, E., De Angelis, L. et al. Carcinogenic effects of long- term exposure from prenatal life to glyphosate and glyphosate-based herbicides in Sprague–Dawley rats. Environ Health 24, 36 (2025).

3. EPA R.E.D. FACTS Glyphosate, https://www3.epa.gov/pesticides/ chem_search/reg_actions/reregistration/fs_PC-417300_1-Sep-93.pdf

4. “Glyphosate,” IARC Monographs–112, http://monographs.iarc.fr/ENG/ Monographs/\vol112/mono112-02.pdf.

5. Gilles-Éric Séralini et al., “Long-Term Toxicity of a Roundup Herbicide and a Roundup-Tolerant Genetically Modified Maize, Environmental Sciences Europe, republished study (2014): 14.

6. Thongprakaisang, S., Thiantanawat, A., Rangkadilok, N., Suriyo, T. and Satayavivad, J., 2013, Glyphosate induces human breast cancer cells growth via estrogen receptors, Food and Chemical Toxicology, 59: 129-136.

7. K. B. Flower, J. A. Hoppin, C. F. Lynch, A. Blair, C. Knott, D. L. Shore, et al., “Cancer Risk and Parental Pesticide Application in Children of Agricultural Health Study Participants,” Environmental Health Perspectives 112, no. 5 (2004): 631–35.

8. Lennart Hardell and Mikael Eriksson, “A Case-Control Study of Non- Hodgkin Lymphoma and Exposure to Pesticides,” Cancer 85, no. 6 (March 15, 1999): 1353–60.

9. Romina P. Coullery, María E. Ferrari, Silvana B. Rosso, Neuronal development and axon growth are altered by glyphosate through a WNT non- canonical signaling pathway, NeuroToxicology 52 (2016) 150–161

10. Céline Gasnier et al., “Glyphosate-Based Herbicides are Toxic and Endocrine Disruptors in Human Cell Lines,” Toxicology 262 (2009): 184–91

11. Anthony Samsel and Stephanie Seneff, “Glyphosate’s Suppression of Cytochrome P450 Enzymes and Amino Acid Biosynthesis by the Gut Microbiome: Pathways to Modern Diseases,” Entropy 15, no. 4 (2013): 1416–63.

12. Anthony Samsel and Stephanie Seneff, “Glyphosate, Pathways to Modern Diseases II: Celiac Sprue and Gluten Intolerance,” Interdisciplinary Toxicology 6, no. 4 (2013):159–84, http://sustainablepulse.com/wp-content/uploads/2014/02/ Glyphosate_II_Samsel-Seneff.pdf (accessed March 21, 2014).

13. Monika Krüger, Awad Ali Shehata, Wieland Schrödl, and Arne Rodloff, “Glyphosate Suppresses the Antagonistic Effect of Enterococcus spp. on Clostridium botulinum,” Anaerobe 20 (April 2013): 74–78.

14. Awad Ali Shehata, Wieland Schrödl, Alaa A. Aldin, Hafez M. Hafez, and Monika Krüger, “The Effect of Glyphosate on Potential Pathogens and Beneficial Members of Poultry Microbiota in Vitro,” Current Microbiology 66, no. 4 (2012): 350– 58.

15. Robin Mesnage, Matthew Arno, Manuela Costanzo, Manuela Malatesta, Gilles-Éric Séralini, and Michael N. Antoniou, “Transcriptome Profile Analysis Reflects Rat Liver and Kidney Damage Following Chronic Ultra-Low Dose Roundup exposure,” Environmental Health 14 (2015): 70.