There is a lot of controversy around the healthiness of coffee. Some studies show that coffee has a very beneficial effect on health, linking it to lower rates of diabetes, Alzheimer’s, and Parkinson’s disease. Coffee is also abundant in antioxidants, which are also linked to health benefits. But, on the flip side, coffee is addictive, can cause energy and mood swings, and is linked to higher cholesterol.

As if the coffee debate weren’t confusing enough, now new evidence is turning up which shows that coffee might be contaminated with harmful chemicals called mycotoxins.

What Are Mycotoxins?

Mycotoxins are a type of toxin which is produced by fungi. Even though people have long known that certain fungi growing in the wild are dangerous, it was only recently that people began to research the health effects of fungi growing on our food.

Many deaths from the 1900s have been attributed to mycotoxins, including thousands of humans. However, it is mainly livestock which have been affected. This is because grains and feeds often have fungi growing on them. According to the FAO, mycotoxins killed 100,000 turkeys in England in 1960, and thousands of cattle and horses in the USSR died from mycotoxins in the 1930s.

There are numerous different types of mycotoxins. The ones which are most commonly found on coffee are Aflatoxin B1 and Ochratoxin A. The first is a carcinogen and may cause liver damage and intestinal bleeding. The second is a weak carcinogen and may also cause harm to the brain and kidneys.

Should You Be Worried about Mycotoxins?

Studies have shown that most coffee beans are contaminated with mycotoxins. One study found that nearly 92% of coffee beans were contaminated even before processing, which means that the fungi would have had more time to grow. Another study found that more than half of green coffee beans and nearly half of brewed coffee was contaminated.

The level of mycotoxin contamination varies. Cheap coffees and blends, which allow more bad beans, have higher levels of contamination. Decaf also has more contamination because caffeine is a natural anti-fungal.

The good news is that most coffee, even low-quality coffee, only contains very low amounts of mycotoxins. This is because manufacturers take steps to reduce mold growth, and roasting also destroys much of the mycotoxins. One European study found that four cups of coffee per day only accounted for 2% of the deemed-safe level of mycotoxin intake.

The Bottom Line?

A wide variety of foods that humans eat are contaminated with mycotoxins, including coffee, wheat, corn, dairy, and peanuts. But these mycotoxins are in such low levels that you probably shouldn’t worry about it. If you want to do something for your health then consider drinking your coffee without so much cream and sugar instead!