‘Totally unexpected finding’: Ketogenic diet may subdue the flu virus, Yale study finds

NEW HAVEN, Conn. — Bad news for all you bread lovers out there. A new study conducted at Yale University has found yet another reason to cut back on the carbs: it may save you a nasty bout with the flu. Researchers say that a ketogenic diet, characterized by essentially no carbs and high fat and protein intake, helped a group of lab mice combat and overcome the influenza virus much more efficiently than another group of mice who had been enjoying a high-carb diet.

The ketogenic, or “keto,” diet has been gaining steam in recent years as a popular diet choice for those looking to lose weight and show off their abs quickly. After eating virtually no carbs for a few days, the human body runs out of blood sugar to use for energy, so instead it begins burning protein and fat to produce energy. This metabolic state, called ketosis, can result in fairly rapid weight loss.

According to the study’s authors, a ketogenic diet activates a specific group of gamma delta T-cells found in the lungs. This activation causes enhanced mucus production among airway cells, making them better equipped to trap the flu virus. Interestingly, up until now this group of T-cells were never even associated with the body’s immune response to the influenza virus.

“This was a totally unexpected finding,” comments co-senior author Akiko Iwasaki, professor of Immunobiology and Molecular, Cellular and Developmental Biology in a release.

After discovering that a keto diet could help block the formation of inflammasomes, a type of immune system activator that can cause a harmful immune response, researchers wondered if dietary choices could also influence the immune system’s overall response to harmful pathogens like the flu. Sure enough, they found that mice who had been fed a ketogenic diet and infected with the flu experienced a significantly higher survival rate than flu-infected mice who had been eating a normal diet.

The keto diet’s beneficial effect on flu response appears to be solely tied to these T-cells, as when mice who been specifically bred without the gene that produces the T-cells were given a keto diet, it failed to protect against the flu.

“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,” adds co-study author Visha Deep Dixit, professor of Comparative Medicine and of Immunobiology.

The study is published in the scientific journal Science Immunology.