4 1/2% of Britons report problems after eating Quorn

A letter published in a medical journal says that a new food ingredient called mycoprotein may cause more frequent adverse reactions than shellfish, milk, peanuts, and other common food allergens. Mycoprotein, sold under the brand name Quorn, is a meat substitute made from vat-grown mold. According to the letter in the American Journal of Medicine by Michael F. Jacobson, executive director of the Center for Science in the Public Interest (CSPI), eating Quorn can cause vomiting, diarrhea, hives, swelling, or even anaphylactic shock.

Quorn has been marketed in the U.S. for less than two years, but has been available for more than a decade in the United Kingdom. In a CSPI-commissioned telephone survey of British consumers, approximately 4 1/2 percent of people who ate Quorn reported adverse reactions. That was a higher percentage of people than reported allergies to shellfish (three percent); milk, peanuts, and wheat (two percent); or other common food allergens.

In contrast, Quorn manufacturer Marlow Foods contends that only 1 out of 146,000 people—or 0.0007 percent—suffer adverse reactions. In other words, Marlow Foods has understated the rate of reactions by a factor of roughly 6,000.

In addition, the letter refers to CSPI’s analysis of 597 reports of adverse reactions attributed to Quorn. Of those people, 67 percent suffered vomiting; 33 percent diarrhea; 6 percent hives or broken blood vessels in the gastrointestinal tract or eyes; and 1 percent anaphylactic reactions. Many people suffered repeated reactions, which helped them identify Quorn as the cause. Most of those reports were collected on a CSPI web site, www.QuornComplaints.com.

“It is quite astonishing that the Food and Drug Administration considers Quorn Foods as ‘Generally Recognized As Safe,’ even though many people have suffered severe vomiting or diarrhea, hives, and even anaphylactic reactions,” Jacobson said. “Many people said that Quorn made them sicker than they ever were before, that cramps and vomiting were debilitating, and that they had to go to their doctor or the emergency room. At a time of widespread public concern about food allergies, it is shocking that the FDA would permit a new food that it knows will sicken countless consumers. The FDA should order it off the market immediately.”

Other recent reports in the medical literature have proven that mycoprotein causes allergic reactions. It is unclear whether it also can cause toxic reactions, but the particular fungus used, Fusarium venenatum, is known for producing mycotoxins. In fact, the word ‘venenatum’ is Latin for venomous. Quorn’s manufacturer, Marlow Foods, contends that the strain of fungus it uses does not produce toxins.

In addition, the British developer of mycoprotein conducted a clinical study in 1977-78 that proved that the product causes sometimes-severe gastrointestinal disturbances. CSPI obtained that unpublished study via a Freedom of Information Act request to the Food and Drug Administration (FDA).

The FDA and authorities in the United Kingdom forced Marlow Foods to change the labeling of Quorn foods, which had falsely claimed that mycoprotein was “mushroom in origin,” “mushroom protein,” or “a small, unassuming member of the mushroom family,” even though it’s made from a non-mushroom processed mold. The FDA has been investigating reports of adverse reactions to Quorn, but CSPI has repeatedly criticized the agency for the glacial pace of its investigation and for allowing its sale in the first place.

Note: Contact CSPI at 202-777-8370 for a copy of the published report. The citation is Am. J. Med. 2003 (September);115:334. This is an update of a press release first issued on Tuesday, September 23.