Fungi in digestive system associated with cognitive impairment can be reduced through ketogenic diet

Specific fungi in the gut-associated with a higher risk of Alzheimer’s disease and found in people with mild cognitive impairment (MCI) can be altered in a beneficial manner by eating a modified Mediterranean-ketogenic diet, researchers at Wake Forest School of Medicine have found.

The small study was published in the current online edition of the journal EBioMedicine.

The foundation of the Mediterranean diet is vegetables, fruits, herbs, nuts, beans, and whole grains. Meals are built around these plant-based foods. Moderate amounts of dairy, poultry, and eggs are also central to the Mediterranean Diet, as is seafood.

The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet that in medicine is used mainly to treat hard-to-control epilepsy in children. The diet forces the body to burn fats rather than carbohydrates.

Principal investigator Hariom Yadav, assistant professor of molecular medicine at Wake Forest School of Medicine, part of Wake Forest Baptist Health, said: “Our study reveals that unique fungi co-living with bacteria in the gut of patients with MCI can be modulated through a Mediterranean ketogenic diet.”

In the single-center, randomized, double-blind crossover pilot study, Yadav’s team identified the organisms in the gut microbiome by sequencing the fungal rRNA ITS1 gene in 17 older adults (11 with diagnosed MCI and six with normal cognition) before and after a six-week intervention of a modified Mediterranean ketogenic diet or the American Heart Association Diet to determine its correlation with Alzheimer’s markers in cerebrospinal fluid and gut bacteria.

“Although we do not fully understand how these fungi contribute to Alzheimer’s disease, this is the first study of its kind to reveal their role in our mental health, which we hope will ignite thinking in the scientific community to develop a better understanding of them in relation to Alzheimer’s disease,” Yadav said. “It also indicates that dietary habits such as eating a ketogenic diet can reduce harmful fungi in the gut which might help in reducing Alzheimer’s disease processes in the brain.”