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Green Living

Are You Eating Toxic Food?

An MIT scientist sounds the alarm about the health-degrading effects of glyphosate, a common weed killer used on many of the crops we eat.

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Q: I used to spray Roundup on weeds in my yard, but I stopped doing that a few years ago after I learned about people who developed cancer after using it. I thought I was protected from exposure, but I’ve since heard from several sources that this chemical is used on many foods that we eat. What can I do?

A: One by one, people are waking up to the far-reaching problem of glyphosate, the active ingredient in Roundup, in our environment and food supply. “I believe that glyphosate is the most dangerous environmental chemical we face today due to its unique mechanism of toxicity, careless application, and pervasive presence,” writes Stephanie Seneff, PhD, an MIT senior research scientist, in her new book, Toxic Legacy. After close to a decade of research on the chemical, Seneff outlines how glyphosate is eroding human health in numerous ways.

Not using glyphosate-based weed killers is the first step toward protecting yourself, but the far trickier step is to avoid indirect or hidden sources of glyphosate, especially in the foods we eat.

The Alarming Rise in Glyphosate Use

It’s hard for many of us to grasp that glyphosate’s use has increased 300-fold since it was introduced in 1974. It particularly skyrocketed after the introduction of herbicide-resistant, Roundup Ready genetically modified organisms (GMOs) in 1996, but glyphosate is not just sprayed on GMO crops. It’s also used as a pre-harvest drying agent on non-GMO crops such as wheat, oats, and legumes. Surprisingly, the highest levels of glyphosate have consistently been found in these non-GMO foods.

Today nearly 150,000 tons of glyphosate are sprayed onto American crops each year—the equivalent of one pound of glyphosate per year for every person in the United States.

Health Problems from Glyphosate

Glyphosate wasn’t on Seneff’s radar for the first 64 years of her life, but since September 2012, she has worked tirelessly to understand the chemical and its effects on our health. The following are key points from her book:

    • Cancer: Excessive DNA damage is a precursor to cancer, and human liver cells and human white blood cells exposed to glyphosate suffer DNA damage. Cancer can take a long time to develop, and the scientific literature points to glyphosate being carcinogenic, “priming the body to fall prey to cancer,” she writes.


    • Liver damage: A large number of studies have demonstrated that glyphosate is markedly toxic to the liver, and that the liver is one of first organs to be affected by glyphosate exposure. This isn’t surprising because it’s the liver’s responsibility to clear toxins from the blood. Research reveals that glyphosate depletes the liver of glutathione, induces oxidative stress (which can lead to DNA damage), and causes fatty liver disease.


    • Harming the gut microbiome: Glyphosate, which was patented as an antimicrobial, is also hurting our guts. It preferentially kills the species of bacteria that we need the most, such as Lactobacillus and Bifidobacteria. These microorganisms help our bodies perform many functions, including digesting food and synthesizing chemicals that affect learning, memory, and mood. When glyphosate destroys beneficial bacteria, harmful disease-causing bacteria and fungi can thrive. Alterations in microbes in the gut are associated with many different conditions—not only digestive problems but also depression and other mental disorders, autoimmune diseases, and Parkinson’s disease.


    • Mineral deficiencies: Glyphosate is a chelating agent, which means it binds tightly to metal ions. The chelation action of the weed killer disrupts a plant’s uptake of essential minerals from the soil—including zinc, copper, manganese, magnesium, cobalt, and iron—which leads to mineral-deficient plants. When we eat these plants, we can become deficient in minerals too. Seneff also writes that glyphosate impairs the body’s ability to maintain adequate sulfate supplies. Sulfate is critical for escorting hormones through the bloodstream, deactivating toxic compounds, shuttling them out of the body, and controlling what goes into and what stays out of most cells in the body.


    • Hormone and reproductive issues: A review paper published in 2020 found that glyphosate exhibits eight of 10 key characteristics of an endocrine disruptor. It has been found to disrupt thyroid hormone regulation, suppress testosterone synthesis, and inhibit an enzyme critical for conversion of testosterone to estrogen. Exposure to glyphosate is linked to reproductive disorders, including fertility problems in adults and birth defects in children. And according to Seneff, the most devastating effects don’t appear until subsequent generations.


(Photo: Getty Images)

Taking Action

Once you understand the magnitude and severity of the glyphosate problem, it’s easy to be overwhelmed. But take heart: As more people become educated about glyphosate, the more they’re taking effective action. After hundreds of thousands of concerned citizens joined the Environmental Working Group’s campaign to get glyphosate out of our food, Kellogg’s announced plans to end the pre-harvest use of glyphosate in all of its crops by the end of 2025. Many other people are joining collective efforts to ban the use of glyphosate, which Seneff says is imperative.

On an individual basis, our food purchases can make a world of difference. Seek out certified organic food or buy real food grown by local farmers who you know do not use glyphosate or other synthetic pesticides. You also can choose products with the Glyphosate Residue Free Label. (See “Seek Out These Food Labels,” below.) Even if you’ve been exposed in the past, the body has an amazing ability to heal itself when you simply remove hazardous substances. So start today! Other tips Seneff recommends in Toxic Legacy include:

    • Savor sulfur: Because it’s important for detoxification, eat lots of sulfur-containing foods such as grass-fed beef, fish, eggs, cheese, onions, leeks, garlic, and cruciferous vegetables. Or consider taking sulfur-containing supplements, such as alpha-lipoic acid, chondroitin sulfate, glucosamine sulfate, MSM, SAMe, liposomal glutathione, taurine, or Aged Garlic Extract. Better yet, soak in Epsom salts to absorb sulfate through the skin and bypass sulfur metabolism in the gut, which can be uncomfortable when our bodies have chronic glyphosate exposure.


    • Heal the gut with pre- and probiotics: Prebiotics are nondigestible plant fibers that are fermented by the beneficial bacteria that live in our intestines. Seneff advises eating foods high in prebiotics, including asparagus, artichokes, bananas, dandelion greens, garlic, leeks, and onions. Probiotics are living bacteria that promote human health. You can obtain probiotics by eating naturally fermented foods such as sauerkraut and yogurt, or by taking probiotic supplements.


    • Eat your antioxidants and polyphenols: To help protect your cells from damage by glyphosate and other toxic chemicals, emphasize food sources of glutathione, vitamin C, and polyphenols. Foods rich in glutathione include asparagus, avocados, okra, and spinach. Good food sources of vitamin C, which will reduce your need for glutathione, include citrus fruits, broccoli, kale, and Brussels sprouts. Foods that contain polyphenols—micronutrients produced by plants to protect themselves against disease, infection, and damage—include many fruits, vegetables, herbs, tea, and coffee.


    • Don’t forget the minerals: Keeping in mind that glyphosate is a major metal chelator, particularly for iron, magnesium, manganese, cobalt, copper, and zinc, consider taking a multiple mineral supplement—or eat mineral-rich foods, such as bone broth, seafood, eggs, and organ meats to boost your intake.


Seek Out These Food Labels

To help you avoid glyphosate in and on foods that you buy, look for these labels.

USDA Organic

By law, glyphosate and other synthetic chemical pesticides, along with synthetic fertilizers, sewage sludge, irradiation, and GMOs, cannot be used in the production of certified organic crops. Even though glyphosate is pervasive in our environment and can drift onto organic crops through wind or rain, research shows that people who eat a predominantly organic diet have significantly less glyphosate in their urine than people who consume mostly conventional foods.

Regenerative Organic Certified

Products that meet Regenerative Organic Certified (ROC) standards must first hold USDA organic certification, which means crops are not sprayed with glyphosate. ROC then adds further criteria to ensure soil health, pasture-based animal welfare, and social fairness for farmworkers.

Products that display the Regenerative Organic Certified label include Dr. Bronner’s Regenerative Organic Coconut Oil, Nature’s Path Oats, Patagonia Provisions Regenerative Organic fruit snacks, and Lotus Foods Brown and White Basmati Rice.

Glyphosate Residue Free

Products bearing the Glyphosate Residue Free label contain no glyphosate, meaning they’re at the bottom limit of detection for the chemical in laboratories, 10 parts per billion. The products are tested by an accredited laboratory at least three times per year, providing extra assurance against glyphosate exposure in foods that consumers buy.

This certification is one of the fastest-growing in the United States, according to Harry Rowlands, director of The Detox Project, the organization that launched the food label in 2018 to create transparency within the food industry, specifically regarding pesticides.

More than 70 food and supplement brands and 1,500 products have been certified, including Chosen Foods oils and mayo, Nutiva oils and seeds, White Leaf baby food, Kettle & Fire bone broth, Soozy’s Grain-Free baked goods, Jovial Foods grain products, Uncle Matt’s juices, Heavenly Organics chocolates, and MegaFood supplements.


Toxic Legacy

Written by MIT scientist Stephanie Seneff, PhD, Toxic Legacy is an exposé of the world’s most common weed killer, glyphosate, and its role in skyrocketing rates of chronic diseases, including cancer, liver disease, and more.

The book also is a call to action. “This issue is too important to ignore,” Seneff writes. “We need to ban glyphosate worldwide. Now.”