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Mycotoxin: What You Need to Know About This Popular Coffee Contaminant

The Bulletproof coffee craze introduced most people to the word and concept of mycotoxins — microbial contamination of food by, essentially, mold spores. Ideally, you only make Bulletproof coffee with mycotoxin-free coffee, or clean coffee, which you can purchase from the company, of course. But how much of a problem are mycotoxins in coffee? The answer is complicated — and there’s a lot more involved than just coffee. Here’s a look at what you should know about mycotoxin poisoning, including mycotoxin symptoms and which foods are most likely to be contaminated.

What Are Mycotoxins?

According to the World Health Organization, mycotoxins are naturally occurring toxins produced by certain molds and fungi. They grow in grains and cereal, nuts, spices, dried fruits, coffee beans, cocoa beans, and apples, among other things. You may also see scientists refer to mycotoxins as metabolites — a chemical by-product of metabolism. In other words, molds produce mycotoxins when they grow and spread. You’ll also find mycotoxins in some animal products, including eggs and dairy products (if the animals ate contaminated feed).

What’s the Problem with Mycotoxins?

Mycotoxins are poisonous to both humans and animals. They cause a variety of adverse effects, including symptoms of acute poisoning. The long-term effects of chronic exposure to mycotoxins may include immune deficiencies and cancer. You can absorb mycotoxins by breathing them in — for example, through exposure to toxic mold in the environment, and also through your skin or through the intestinal lining if you eat foods contaminated with mycotoxins.

What Foods are Contaminated with Mycotoxins?

Scientists have identified several hundred mycotoxins, but most research focuses on a small handful that seems to present the most danger to humans and livestock — aflatoxins, ochratoxin A, patulin, fumonisins, zearalenone, and nivalenol/deoxynivaleno. The mycotoxin most likely to affect coffee beans, cacao beans, grapes, cheese and dried fruit or wine from vine fruits is ochratoxin A. You may encounter aflatoxin in nuts, seeds, and grains, including rice, wheat and maize or corn.

What are the Effects and Symptoms of Mycotoxin Exposure?

Mycotoxin poisoning — mycotoxicosis — has so many symptoms and malign effects that the mycotoxin symptom list reads like a laundry list of every ailment known to man. It’s like the opposite of the hyperbolic claims for superfoods that cure everything — except these toxins actually do seem to be at the root of a huge list of symptoms and long-term effects.

According to a review of literature published in Frontiers In, mycotoxins may cause cancer, mutate genes, affect the immune system, damage your kidneys or liver, cause skin rashes and other skin symptoms and affect the neurological system.

Another review published in Clinical Therapeutics notes that the effects and symptoms of mold exposure include:

  • Asthma
  • Wheezing
  • Bronchitis
  • Fatigue
  • Musculoskeletal pain
  • Headaches
  • Anxiety
  • Mood swings
  • Cognitive impairments
  • Depression

Some research even suggests a link between exposure to mycotoxins — including ochratoxin A, most commonly found in coffee — and autism spectrum disorder.

How Big a Problem Are Mycotoxins?

The FAO — the United Nations Food and Agriculture Organization — estimates that 25 percent of the world’s food crops are contaminated with mycotoxins. Mold is practically unavoidable, but many countries, including the United States — regulate how much mycotoxins can be present in food that’s imported or sold in their countries. Newer research, however, is suggesting cumulative effects of long-term exposure to mycotoxins, so it’s difficult to set “safe” levels of exposure. The truth is that many of the foods you consume every day are probably contaminated with mycotoxins. But there are ways to limit your exposure.

How to Limit Your Exposure to Mycotoxins in Food

You can limit your exposure with some common-sense routines and actions, such as the following recommended by the WHO:

  • Inspect whole grains, nuts, dried figs and other foods that are commonly contaminated for any signs of mold, and discard any that look discolored, moldy or shriveled.
  • Store food properly to prevent mold from growing.
  • When you buy nuts, grains, fruits or coffee — especially green coffee — buy it as fresh as you can get. — Purchasing fresh products reduces the likelihood that the foods have become contaminated by improper storage.
  • Don’t keep food for too long before using it.
  • Eat a healthy, diverse diet. A nutritious and well-balanced diet will strengthen your immune system to deal with any exposure more efficiently.

Finally, you can buy mycotoxin-free coffee if it makes you feel safer, but most experts say that’s not necessary. They do suggest, however, that you buy higher quality coffee — cheaper brands are more likely to have higher levels of mycotoxins — and store your coffee beans in a cold, dry place to discourage the growth of mold.

Deb Powers is a freelance writer living and working in Massachusetts. She writes frequently about health, wellness and lifestyle topics.


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