Poisonous ‘False Morel’ Mushrooms Linked to Devastating Neurological Disorder

French Alpine Village Sees Cluster of ALS Cases

A potentially deadly lookalike of a prized culinary mushroom may be the culprit behind a baffling surge of a debilitating neurological disease in a remote French Alpine village. Experts are investigating a possible link between the consumption of “false morels” and Amyotrophic Lateral Sclerosis (ALS).

Mystery Illness in Montchavin

The small ski village of Montchavin, home to around 200 residents, has reported 16 cases of ALS in the past decade. This rate is astronomically higher than the global average, suggesting an environmental trigger. Neurologist Dr Emmeline Lagrange of Grenoble University Hospital first noticed the unusual cluster when several patients from the village were diagnosed with the fatal neurodegenerative disease.

None of the affected individuals had genetic predispositions or family histories of ALS, also known as Lou Gehrig’s disease or motor neurone disease. This progressive condition leads to paralysis and is typically fatal within two to five years of symptom onset.

The False Morel Connection

False morels, belonging to the *Gyromitra* genus, are often mistaken for true morels, a gourmet delicacy. However, these poisonous fungi contain hydrazines, including gyromitrin, a substance toxic to the nervous system and a known carcinogen. The symptoms of false morel poisoning can range from gastrointestinal distress to severe neurological effects like seizures and organ failure.

Environmental neuroscientist Dr Peter Spencer of Oregon Health & Science University identified a potential link when he learned about the Montchavin cases. His prior research had explored how toxins in cycad seeds contributed to ALS-Parkinsonism dementia in Guam, noting that a metabolic byproduct of cycasin, methylazoxymethanol (MAM), is also produced when the body processes hydrazine. This chemical similarity pointed to a potential common cause.

Dr Lagrange’s investigation revealed that many ALS patients in Montchavin had a history of intentionally seeking out false morels, believing they possessed rejuvenating properties. “They are always in a group, a secret group, a social network, and they eat the mushrooms. And they all knew that it’s forbidden,” one villager reportedly told Dr Lagrange.

“All ALS cases but none of the controls had a history of consuming acutely poisonous False Morels, notably the Snow Morel Gyromitra gigas.”

—Dr Emmeline Lagrange

Researchers found that ALS patients had consumed false morels, sometimes for up to 20 years, before symptoms appeared. In contrast, a control group of villagers who ate wild mushrooms but avoided false morels did not develop the disease. “Since no other significant chemical or physical exposure was found, the primary risk factor for ALS in this community appears to be repeated ingestion of these neurotoxic fungi,” Dr Lagrange concluded.

A Global Culinary Conundrum

Despite their dangers, false morels, particularly *Gyromitra gigas*, are considered a delicacy in parts of Scandinavia. Finland even featured the mushroom on a postage stamp in 1974, with the Finnish Food Authority advising thorough boiling and rinsing before consumption. However, misidentification remains a risk, as illustrated by a 2024 study in Michigan that documented 118 cases of false morel poisoning between 2002 and 2020, leading to symptoms like vomiting, diarrhea, liver damage, and neurological effects.

Globally, ALS affects approximately 33,000 Americans, with genetics accounting for only 10-15% of cases. Environmental factors like pollution, heavy metals, and head injuries are also implicated. The ongoing investigation in Montchavin underscores the critical need for accurate mushroom identification and highlights the potential for even obscure food sources to carry profound health risks.