Safety of This Fungus-Derived Food Product

If you shop for meat substitutes, you may have noticed something in the freezer section called Quorn (pronounced "kworn"). It's the brand name for food products made with mycoprotein, derived from the soil fungus Fusarium venenatum.

The fungus is fermented in vats and the resulting paste is mixed with egg whites and flavorings and shaped into various meat-like forms, such as burgers, cutlets and chicken-like nuggets. Compared to other meat substitutes, it has a more "meaty" texture and taste.

Quorn is high in protein and fiber and is a good source of selenium and zinc. Marketers say it helps control cholesterol, blood sugar and weight. Sounds like a perfect vegetarian option—but it has been the subject of much controversy.

What's in a name? Quorn was originally promoted as "mushroom in origin," which sounds more appealing than calling it a fungus. But mycoprotein is not a mushroom (not all fungi are mushrooms), and the American Mushroom Institute, the Center for Science in the Public Interest (CSPI), and even some other food companies took issue with the labeling. It's now described as an edible fungus, like mushrooms and truffles—which, as opponents say, is still somewhat deceptive. And it's hardly "all-natural," as it's often touted, since it is highly processed.

A matter of safety. The Food and Drug Administration (FDA) categorizes mycoprotein as GRAS (generally recognized as safe), but more than 1,500 adverse reactions have been reported to CSPI, including severe abdominal pain, vomiting, diarrhea, and hives. Several people have suffered breathing difficulties and even anaphylaxis (a life-threatening allergic reaction).

Not surprisingly, a mycoprotein website lists a very low estimated risk of adverse reactions and says the most common side effect is just flatulence, due to the fiber. CSPI is urging the FDA to revoke Quorn's GRAS status, or at least to require warning labels.

What about the health claims? Several studies, most from the early 1990s, suggest that mycoprotein may have positive effects on cholesterol, blood sugar, and satiety. But they were small, short, and often flawed. The only recent study, a small company-funded one in 2010, suggested a link between mycoprotein and improved cholesterol—but this study had problems, too. The potential health benefits may be due to the specific types of fiber in mycoprotein (beta-glucans and chitin).

Bottom line: There are other meat alternatives, including those made from soy, that don't carry the risk of serious adverse reactions that have been reported from Quorn (unless, of course, you're allergic to soy or their other ingredients). Keep in mind that all processed meat substitutes, including Quorn, tend to be high in sodium and sometimes saturated fat from added cheese and other ingredients.

Source: Originally published in The University of California, Berkeley Wellness Letter (May 2011)

Publication Review By: the Editorial Staff at

Published: 07 Apr 2011

Last Modified: 16 Mar 2015