Pesticides and Your Gut Microbiome

Environmental toxins are everywhere; from pesticides to PFAS, VOCs to heavy metals, environmental toxins have invaded every corner of our lives. And many are carcinogenic, endocrine disruptors and a contributing cause of chronic illness through the disruption of our gut bacteria. It can be a difficult topic to navigate as there is so much to learn (but that’s why I am here!) This will be the first post in a series: “Environmental Toxins and Your Health.” My aim is to help you by chewing up this massive topic into bite sized, very digestible chunks, so that you can make informed decisions about your health.

Pesticides are chemical substances used to destroy pests such as insects, rodents, weeds or fungi. Although commonly used within agriculture, they are also widely used at golf courses, on turf, greenhouses, utility posts, etc., and have been since the late 1800s. One of the most commonly known is “RoundUp”, and it’s active ingredient Glyphosate, which has been labeled a probable carcinogen, along with many other commonly used pesticides.

Pesticides are widely used in industrial farming.
Pesticides are widely used in industrial farming.

There are many different ways that we are being exposed to pesticides without realizing it. Did you know that pesticides have been one of the most commonly detected contaminants in indoor air? Or that indoor air pollution is one of the 5 top health issues in America? “Exposure to pesticides have been known to be associated with elevated chronic diseases such as cancer, diabetes, ALS, Alzeihmers, birth defects, etc..” Studies were conducted on pregnant women, farmers and children, showing that pesticides even impaired childhood brain development, doubling the odds of leukemia and brain tumors.

PESTICIDES & our GUT Bacteria

But how does this relate to your gut microbiome? Your gastrointestinal tract acts as a physical and biological barrier against all manner of harmful things. When it comes to pesticides, it is the first exposure site. Studies have shown that certain pesticides can promote obesity and insulin resistance in mice via the gut microbiota. Experts continue to find that the disruption of the gut microbiota equilibrium may create a chronic low grade inflammation leading to obesity associated diseases.

A commonly used organophosphate insecticide is diazinon. Not only was it used for conventional agriculture but also for home insect sprays and lawn care products up until 2004. Although it was banned for concerns over human and wildlife health, it is still widely available. Many studies show that when mice were exposed to this pesticide, their gut microbiome was directly impacted, leading to the proliferation of pathogenic bacteria. These types of gut bacteria are directly related to respiratory infections and irritable bowel syndrome in humans.

Another study showed firm evidence that exposure to pesticides, even at assumed “safe” levels, were negatively affecting our gut bacteria. It also showed that even low doses of glyphosate-based products not only contributed to fatty liver disease but death of liver tissue as well. Imbalances in the gut microbes have already been linked to several diseases and studies showed that pesticides were affecting the Shikimate Pathway, the way in which many bacteria create amino acids. Scientists speculated that perhaps the effects from pesticides on the Shikimate Pathway within our gut microbiome was contributing to these diseases.

There are over 85 different types of these chemicals currently approved within the U.S., and are all found in groundwater, drinking water and the air. Eating conventional fruits and vegetables, unknowingly trailing these pesticides into your home and/or using these chemicals on your lawn or garden is increasing your exposure and risk for disease.

So what should you do?

Properly cleaned produce is great for your gut bacteria!
Properly cleaned produce is great for your gut micribome!

Minimize your daily exposure! Here’s how:

  • Go organic. The harmful pesticides we’ve discussed are not allowed to be used in organic produce. Organic food also has a wealth of other health benefits. It has been proven to have higher levels of phenolic phytonutrients, which are plant-based compounds that have antioxidant and anti-inflammatory properties and may reduce the risk of cardiovascular diseases and cancer. These phytonutrients are so powerful that they enhance immunity, detoxify carcinogens and repair damage from exposure to toxins. Regular fruits and vegetables have them as well, just not in as high quantities as organic foods.

  • Don’t just go organic for your produce! Pesticides are used on cotton farms, too! Make sure to buy organic wherever cotton is involved, including tampons and/or pads. This is a big one that sometimes goes unnoticed! If you’re looking to take the next step, try a menstrual cup or period underwear for not only safer but environmentally friendly alternatives.

  • Wash your produce! Even if you buy organic, it is always important to thoroughly wash your fruits and vegetables. A study showed that pre-soaking apples, tomatoes, lettuce and broccoli in either a 5% vinegar solution or 15% lemon mixture and then rinsing under water worked similar to scrubbing and rinsing under cold water. Be careful with commercial produce washes as these can sometimes contain less than ideal ingredients.

  • Adopt a “no shoe” policy at home. Try and have a designated home pair of sandals or slippers that you can change into. If you feel strange asking guests to remove their shoes, there are special floor mats meant to help decrease the spread of pesticides within your household. Your guests can simply wipe the bottom of their shoes with the mat.

  • Look for less toxic versions of flea and tick treatments for your pets. Also remember to always wear gloves when applying and to follow the directions thoroughly.

  • One last precaution we can take is to speak with your landscapers and ensure they are not using pesticides on your lawns. People often walk around barefoot in their backyard but that is another easy way to expose yourself and your home. Ensure that they use other methods of pest control, such as insect-repelling plants and other natural repellants. Nature is pretty incredible and can provide us with the tools we need. Natural repellant plants include marigolds, sunflowers, lavender, petunia, lemongrass, rosemary, and chrysanthemums.

Remember, try to not get overwhelmed with information. Take bite sized pieces and make small, weekly changes to your routine and add healthier choices as you become more comfortable. The goal is to make long-term, sustainable changes. There are opportunities to improve every day and with knowledge, we can use every decision to live a healthier, cleaner lifestyle.


To optimize your Gut Health, download Dr Mendez Gut Health Guide! If you are looking for support to help improve your diet and boost your gut microbiome, then get in touch today or register to make an appointment to discover how Doctor Méndez can help you to optimize your health.

–Written in collaboration with Cynthia Romero


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