Our Moldy World Part 1: Mycotoxins

moldy bread

Some new research has come to light that provides an explanation for why the problem of mycotoxins (mold toxins) in our food supply is becoming worse. This may be the most important post I’ve ever written when you consider how little is known about this information and how big of a problem mycotoxins are for your health and performance.

This blog post is the story of how we accidentally created a monster in our soil, in our homes, and in our food.

The Bulletproof Diet is designed to reduce as many toxins as possible in food, including mycotoxins, the name for toxins formed by yeast and fungi. You’ll find almost no one in the health and wellness community writing about these toxins, although I hope to change that in my upcoming book about nutrition for pregnancy.

We only learned to detect many of the mycotoxins after 1985 and we’re still discovering them, although the first known mycotoxin is ubiquitous. It’s penicillin, the mycotoxin that a fuzzy mold on a cantaloupe produced to kill any bacteria foolish enough to try to also eat the cantaloupe. Alexander Fleming discovered this in 1928, and we’ve been looking for more ever since, and finding them. Another potent mycotoxin is LSD, which is derived from the ergot fungus on grains.

Think about how powerful those are. The tiny antibiotic pill that can cure infection, or the even smaller amount of ergot required to cause potent hallucinations. This should give you an idea of how important some of these toxins are in very small amounts.

Frankly, I wish we were only dealing with antibiotic forming molds and hallucinogens in the food supply. It’s much worse than that. We are facing extremely potent xenoestrogens that cause rapid weight gain and decimate fertility in all mammals including people. There are also potent mutagens that cause cancer. On top of that, we have other mycotoxins implicated in a host of cardiovascular and nervous system diseases, and others that depress RNA synthesis. These things are in our food supply, and many are unregulated.

Other than studies on mycotoxins, I have never seen a nutritional study control for the presence of mycotoxins in the diet even though mycotoxins can have a huge impact on weight gain. Cattle ranchers know about this –they use a purified form of the zearalenone mycotoxin to quickly fatten cattle on less food. (Of course, when you eat those cattle, you will quickly fatten too…)

Round-up: Biohacking the Planet’s Soil “Probiotics” since 1964

Mycotoxins weren’t always such a problem for mankind. We have used them for years when we ferment foods and allow the toxins–including alcohol–formed by yeast to preserve our food. The problems we’re facing now began in 1964. That’s when Stauffer chemical company patented glyphosate, the herbicide now commonly known as Round-up™.

Glyphosate acts by chelating (chemically binding) essential nutrients in soil or in plants, things like zinc, iron, manganese, or copper. This is one of the reasons Round-up™ causes skeletal deformations.  The problem is that soil is a living organism, a complex system, and the microbes in soil are affected by glyphosate too. Soil microbes are to the planet what probiotics are to your gut. Soil microbes keep pathogenic fungi from becoming dominant. In the past 30 years, we have used glyphosate with reckless abandon, and it has destroyed the balance in the soil.

According to Dr. Don Huber, an agricultural scientist and expert in microbial ecology, glyphosate not only destroys protective bacteria in soil, it also promotes more aggressive and virulent pathogens.

It’s Dr. Huber who provides a smoking gun here:

“What we see with the fusaria, which causes sudden death syndrome in soybeans, is that it can be stimulated by glyphosate… so we find [up to] 500 percent increase in root colonization by this fungus. It’s a very serious pathogen, not only on soybeans. Fusaria on most of our crops is a major disease organism that we have to deal with.”

Fusarium is a particularly potent fungi that creates havoc in our agricultural system because it contaminates almost all corn and a lot of wheat and other grains. Even worse, it’s on coffee. (one of the many reasons I created Bulletproof Upgraded Coffee)

Fusarium creates more than a dozen known mycotoxins. The 3 categories you should be thinking about are:

–          Fumonisins which are linked to nervous system irregularities and cancer.

–          Trichothecenes which are the most potent and damaging for people.

–          Zearalenone which is a potent xenoestrogen.


Fumonisin comes in two flavors, B1 and B2. B1 is very scary because corn has been reported worldwide to contain milligrams of fumonisin B1 per kilogram, but B1 starts to affect our health at of micrograms per day. B1 destroys liver and kidney function in all animals tested including people. In people B1 Fumonin causes esophageal cancer and defects of the brain and spinal cord in the human embryo known as neural tube defects. B2 is like B1 but is more mild (at least in chicken embryos).


I have a personal beef with trichothecenes because I’ve lived in water damaged buildings with mold contamination, most likely from stachybotyris, the dreaded “black mold” that also makes trichothecenes.

These toxins work because they are powerful inhibitors of protein synthesis. They react with parts of the ribosome inside a cell and work on contact with your skin or G.I. tract. They don’t need to be metabolized to start harming cells.

Trichothecenes are also used in biological warfare.

In 1950, trichothecenes from fusarium contaminated grains killed 100,000 Russians.  (Joffe, A. Z. 1950. Toxicity of fungi on cereals overwintered in the field: on the etiology of alimentary toxic aleukia. Dissertation, Inst. Bot. Acad. Sci. Leningrad. P. 205.

Just think: that happened before we supercharged fusarium by abusing glyphosate for 30 years.


Zearalenone is well-known by ranchers because it is the primary toxin that causes infertility, abortion, and other breeding problems. Pigs, which have a reproductive system similar to humans, are the livestock most affected by zearalenone. In pigs, levels above 30 parts per million affect semen and hair loss, and exposure to only 3 ppm towards the end of pregnancy creates birth defects.  Zearalenone also causes imbalances in sex hormones.  Young pigs are especially susceptible, as are humans.  In mice, zearalenone causes DNA damage, and is thus a potential carcinogen.

All of this is on top of the rapid fat gain caused by Zearalenone.  Round-up™ is bred into plants like corn.  This means you are getting a double dose of sex organ destroying chemicals, because Round-up™ is also toxic to human reproductive tissue.

Perhaps the worst part is when multiple strains of mycotoxins are present at the same time.  There is evidence these compounds work synergistically to produce negative effects more powerful than the sum of their parts.

This blog post is only half the story of how we got here. Monsanto’s Round-up™ is just one of the two main chemicals that turned our planet’s relatively benign microbial ecology against us. The other is a gift from DuPont, but that will be the topic of another post.

Please watch my mycotoxin video if you’d like to learn more about mycotoxins.

None of this is meant to be alarmist. I’ve read just about every book I can find on mycotoxins, excluding some university level biochem textbooks. I have personally experienced the effects of mycotoxin exposure and it played a major role in my former obesity and chronic illnesses. I am a part of the 28% of humanity that is genetically predisposed to not excrete mycotoxins very well.

Every person I have worked with who has taken the time to reduce their exposure to mycotoxins from their diet and their living environment has experienced significantly improved health and performance. These very powerful, mostly invisible chemicals have a huge impact on how we think and feel every day. Fortunately, most of the time, they can be hacked.  Removing mycotoxins from your food and environment is key to losing fat, improving your mental performance, living longer, and being more.





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