The Many Health Concerns Associated With Glyphosate


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Used by farmers and agricultural workers across the globe, glyphosate is the active ingredient in herbicides. It is one of the most common environmental pollutants, with glyphosate residues being found in personal care products, tap water, rainwater, sports fields, public parks, lawns, waterways, animal feed, and many of the conventional foods you eat every day. (25) The stance that glyphosate is harmless to humans has been long maintained, with claims even stating it is “safer than table salt”. (2)

What is glyphosate?

In recent news, several lawsuits over glyphosate’s link to various cancers have been lost by companies who have paid billions of dollars in settlements. (28) With the American Cancer Society adding glyphosate to their list of “Known and Probable Human Carcinogens” and the World Health Organization categorizing glyphosate as “probably carcinogenic to humans”, it’s important to encourage additional research into investigating the safety of glyphosate and its link to cancer in humans. (1)(26) Research has already revealed how this pesticide can negatively impact the gut microbiome in ways that may cause significant metabolic issues, creating the perfect environment for the development of chronic diseases. (18)

Foods with high glyphosate residue

Research has revealed some of the most common foods that contain glyphosate at high levels, including:

  • Apples
  • Canola
  • Celery
  • Cherries
  • Corn
  • Grapes
  • Kale
  • Pears
  • Potatoes
  • Processed foods (such as cereals, granola bars, snack bars, potato chips, and oatmeals)
  • Soy
  • Spinach
  • Strawberries
  • Sugar beets
  • Tomatoes
  • Wheat (6)(18)(23)

Why is your microbiome important?

Your gut microbiome helps with producing nutrients and proteins needed to make neurotransmitters and hormones; influences inflammatory responses, genetic regulation, immunity, and energy production; and plays a role in liver detoxification, anti-oxidant production, brain health, and behavior. (4)(10)(17)(18)(21)

Altering effects of glyphosate on the microbiome

Glyphosate’s mechanism of killing weeds and other problematic organisms is through the inhibition of a metabolic pathway that does not exist in humans but is found in plants, fungi, and bacteria. (3)(5) This pathway is called the shikimate pathway and it is present in the trillions of microorganisms that colonize your body and make up your microbiome. (19)

man in yard taking out all the weeds

Glyphosate is used to kill weeds, so when it enters your body it is killing balancing bacteria in your microbiome.

Similar to the effects of an antibiotic, (19) chronic glyphosate exposure affects the delicate balance of bacteria in the gut and can lead to microbiome alterations. Research has shown that glyphosate exposure may lead to notable imbalances and decreased microbiome diversity in mammals. (18)(19)(22) We now know decreased diversity is associated with many chronic health conditions. (27)

Altered gut microbiome health conditions

When the gut microbiome is affected, many health conditions are associated to this change. These conditions include:

Microbiome alterations and metabolic issues

Glyphosate’s disruption of the gut microbiome causes a cascade of other metabolic issues down the line. This is because gut microbes aid the body in the production of dozens of nutrients and are involved in the synthesis of neurotransmitters/hormones such as serotonin, epinephrine, dopamine, and thyroid hormones. (3)(19)

Glyphosate may also impair the function of certain liver enzymes involved in disposing of substances through bile acids. These disruptions may affect the production and metabolism of various nutrients that depend on these pathways, including:

These nutrients, hormones, and neurotransmitters are needed for hundreds of metabolic processes that occur in the body and control everything from energy production to bone integrity. Chronic glyphosate exposure has the potential to contribute to vitamin/mineral deficiencies, mood disorders, thyroid issues, gastrointestinal disorders, hormone disturbances, (19) infertility, sleep disturbances, (18) and immune disorders. (12)

Microbiome alterations and fertility

One of the most notable downstream effects of the metabolic disruption glyphosate creates are the fertility issues. (11)(16)(18) Puberty has been occurring at much earlier ages than ever before, (7) and infertility, (11) PCOS and other hormone imbalances are on the rise. (8) New research suggests that glyphosate has an impact on erectile dysfunction and male fertility by decreasing sperm count. (11) Not only can glyphosate cause changes in estrogen production and fertility problems in both men and women, but higher exposures to glyphosate during pregnancy may increase the risk of low weight, premature babies. (11)(13)(16)(18)

pregnant woman looking down at her child and holding her near her belly

Be aware of the effects of glyphosate on fertility, pregnancy, and hormonal health.

There are also disturbing observational studies linking parental glyphosate exposure to increased chances of a cancer diagnosis in their offspring. (20) With fertility problems on the rise all over the world, glyphosate residues found on our food and in our water may be a key player in this dilemma. (18)

The bottom line

Current evidence regarding the safety of glyphosate suggests that there may be long-term consequences to our health, ecosystems, and the environment. Eating organic food may be a more significant factor in maintaining health and avoiding chronic disease than has been previously recognized. (1)(18)(26)

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More about the author

Dr. Bay received her Doctor of Chiropractic, Master’s in Human Nutrition and Bachelor of Science in General Studies: Natural Sciences & Mathematics degrees from the University of Bridgeport. She has additional certifications as a certified nutrition specialist and certified dietician nutritionist. In addition to private practice, Dr. Bay has worked with various HIV nonprofit organizations, providing functional nutrition protocols for HIV patients with various health issues such as: diabetes, kidney disease, cardiovascular disease, cancer and several other HIV related comorbidities. Dr. Bay makes a point to attend a variety of functional medicine and nutritional seminars throughout the year, in an effort to remain well informed of the rapidly changing techniques and protocols available to her patients. Dr. Bay received an award from the LGBT Network in December 2019, for her work in the HIV community.

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