11/18/2009 05:12 am ET Updated Nov 17, 2011

Meet Quorn: This Fungus Ain't No Portobello

I should say from the beginning that I have nothing against fungi.

I love my sauteed shitakes and occasional grilled Portobello. I have nothing but respect for the humble, industrious yeasts that help turn flour and grape juice into bread and wine, respectively. I'm not much of a cheese eater, but even I can appreciate the mysterious molds that give Roquefort and Gorgonzolas their distinctive veins. And should I contract strep throat, pass the penicillin, please!

Of course plenty of fungi are considerably less savory, making their homes in shower stalls, locker rooms, and stinky socks.

But when it comes to eating, I draw the line at Quorn, and so should you.

Meet Quorn-brand foods. In the 1960s, scientists and others became alarmed by the prospect of a global shortage of edible protein. In 1967, some British scientists thought they found the answer: A fungus growing in the dirt near Buckinghamshire, England. Quorn's copywriters describe the discovery thusly on packages:

After 15 years of searching in many parts of the world, we finally found what we were looking for. And it was literally growing in our own backyard!

The British scientists found that with some poking and prodding, this fungus could be grown in vats and then processed into an edible, low-fat, high-protein paste. Approved for sale in the U.K. in the 1980s, Quorn's so-called mycoprotein hit the grocery shelves in the form of meat-free burgers, cutlets, and in time, uniquely British things like "Cottage Pie," "Cornish Pasties," and "Toad in the Hole."

Around 2002, the makers of Quorn brought it to America.

Keep in mind that unlike the mushrooms that have been eaten for millennia, this is a new entrant into the human food supply. There had been remarkably little safety testing done of Quorn's fungus, though what had been done wasn't all that reassuring. One early company-sponsored test found that 10 percent of 200 test subjects who ate the fungus experienced nausea, vomiting, or stomach ache, compared with five percent in a control group.

The Latin name of the fungus, Fusarium venenatum, should have tipped off regulators: venenatum means 'venomous.' But most Americans would probably be surprised to learn that the Food and Drug Administration (FDA) does not actively investigate and "approve" new foods, as such. Rather, it simply requires manufacturers to self-affirm that the substance is "Generally Recognized as Safe," or GRAS. It's the same loosey-goosey regulatory framework that has grandfathered in other problematic ingredients like partially hydrogenated oils (the source of artery-clogging artificial trans fat) and salt (a major cause of high blood pressure, heart attacks, and strokes).

So now Quorn's Toad is out of the Hole, as it were. And its sunny orange packaging is now a familiar sight in the frozen food aisles at "health food" stores, Whole Foods, and some other supermarkets. Since the Center for Science in the Public Interest began logging complaints about Quorn in 2002, we've heard from more than 1,400 people who have experienced everything from mild nausea to projectile vomiting, and even life-threatening anaphylactic shock. Our lawyers are now assisting a woman who is suing to get the company to place warning labels on the product about those problems.

If you are already eating Quorn and haven't experienced any of these adverse reactions, you probably don't need to stop. But if you don't want to risk any of these symptoms, I'd opt for something else.

The FDA's policy has been that if a substance does not cause permanent, severe harm, it may appropriately be considered GRAS. Frankly, that's nuts. There is fresh new leadership at the FDA, so I hope they take a long, careful look at Quorn--and their broader policy on when something is GRAS. On Quorn, I hope the FDA applies a massive dose of regulatory fungicide.