Ketogenic diet may help tame flu virus

Mice fed a ketogenic diet were better able to combat the flu virus than mice fed food high in carbohydrates, according to a new study by researchers at Yale University and published in the journal Science Immunology.  

The ketogenic diet, which for people includes meat, fish, poultry, and non-starchy vegetables, activates a subset of T cells in the lungs not previously associated with the immune system's response to influenza, enhancing mucus production from airway cells that can effectively trap the virus, the researchers report.

Researchers led by Akiko Iwasaki, PhD, and Visha Deep Dixit, DVM, PhD, had previously found that immune system activators called inflammasomes can cause harmful immune system responses in their host, and that the ketogenic diet blocked formation of inflammasomes, respectively. The team wondered if diet could affect immune system response to pathogens such as the flu virus.

The researchers found that mice fed a ketogenic diet and infected with the influenza virus had a higher survival rate than mice on a high-carbohydrate normal diet. Specifically, the researchers found that the ketogenic diet triggered the release of gamma delta T cells, immune system cells that produce mucus in the cell linings of the lung, while the high-carbohydrate diet did not.

When mice were bred without the gene that codes for gamma delta T cells, the ketogenic diet provided no protection against the influenza virus, researchers said.

"This study shows that the way the body burns fat to produce ketone bodies from the food we eat can fuel the immune system to fight flu infection," Dixit said.