The Risks of False Morel Mushrooms
A particularly hazardous relative of a gourmet favorite could pose significant health risks to mushroom enthusiasts. The true morel is a highly prized wild mushroom, celebrated in fine dining for dishes like risotto and creamy sauces thanks to its rich, earthy flavor and limited seasonal growth.
However, morels have dangerous impostors. The false morel has misled many amateur foragers and has gained a following in Montchavin, a small village in the French Alps, where locals believe in its “rejuvenating” effects. Despite its name, the false morel belongs to a different fungal family—the Gyromitra.
These false morels harbor toxic hydrazines that can affect the nervous system. While symptoms might include stomach discomfort and diarrhea, severe cases may lead to seizures and even organ failure. The primary toxin, gyromitrin, is also known to be carcinogenic.
Recently, researchers have suggested a possible connection between the consumption of false morels and an uptick in Amyotrophic Lateral Sclerosis (ALS) cases in Montchavin, particularly concerning a mysterious cluster that has emerged over the last decade.
ALS, or Lou Gehrig’s disease, is a devastating neurological condition that leads to progressive paralysis and is ultimately fatal. In a village with about 200 residents, 16 cases have been reported over the past ten years, which is markedly higher than the global average of two to three cases per 100,000 people annually.
When adjusted for population size, Montchavin’s rate of ALS cases would equate to about 800 per 100,000 residents per year. Dr. Emmeline Lagrange, a neurologist at Grenoble University Hospital, spearheaded the investigation after a local resident presented with neurological issues and was diagnosed with ALS.
Upon further inquiry, Lagrange discovered multiple ALS cases within the village. Notably, none of the patients had genetic mutations that might predispose them to the condition, nor did they share a family history of ALS, which typically results in worsening paralysis and death within a few years.
Currently, the causes of ALS remain largely unknown, affecting roughly 33,000 individuals in the U.S. Genetics contribute to about 10-15 percent of cases, while other potential environmental factors include pollution, smoking, heavy metal exposure, and prior head injuries.
The investigation caught the attention of Dr. Peter Spencer, an environmental neuroscientist from Oregon Health & Science University. He has explored a theory linking food to ALS, noting that toxic compounds in cycad seeds were implicated in an epidemic of ALS-Parkinsonism dementia among Guam’s Chamorro people. At its worst, that condition was 50 to 100 times more common there than elsewhere.
Spencer has spent over forty years studying these links and believes that cycasin—a toxin in cycad seeds—breaks down into methylazoxymethanol (MAM), a neurotoxin. Interestingly, MAM is also produced when the body metabolizes hydrazine, found in false morels.
After reviewing Lagrange’s findings, Spencer noticed mentions of mushrooms. Curious, he inquired about what specific types had been consumed, linking them to the conditions he’d studied.
Collaboration began for a study, and they learned that ALS patients in Montchavin had actively sought false morels, despite knowing their consumption is illegal. One villager noted the existence of a “secret group” that foraged for these mushrooms.
In this research, the team studied patients who had consumed false morels alongside villagers without ALS who had eaten other wild mushrooms. Some ALS patients reported gathering up to six pounds of these toxic fungi annually, and many had been doing so for two decades before any symptoms emerged.
All ALS patients examined had histories of consuming the particularly hazardous Gyromitra gigas, while none of the controls did. Lagrange concluded that repeated ingestion of these neurotoxic mushrooms is likely the primary risk factor for ALS in this community.
Despite their toxicity, false morels are considered a delicacy in some parts of Scandinavia, featured in high-end restaurants for their unique taste. In Finland, they even appeared on a postage stamp in 1974, and the Finnish Food Authority recommends thorough cooking to minimize risks.
Amateur foragers often confuse false morels, which appear reddish-brown and brain-like, with true morels, which are typically green or gray. A recent study documented numerous poisonings in Michigan resulting from false morels, with many patients experiencing gastrointestinal distress and some suffering from liver damage or neurological symptoms.
