Beyond weight loss, the ketogenic diet has been shown to have numerous therapeutic benefits. Everything from neurodegenerative diseases to psychiatric disorders have been researched. A new paper published out of Yale University explored a new topic: the flu.
The flu is a common infection caused by the influenza A virus (IAV). When an individual is infected with this virus, the immune response our body produces is heavily influenced by a variety of factors, including diet. This research team at Yale hypothesized that since a low-carb, high-fat ketogenic diet had been shown to promote immune cell response in the lungs, in previous studies, it may combat or improve symptoms of the flu.
Results of this Study
In this study, mice were fed a ketogenic diet for one week before being inoculated with the influenza virus. The effects of the viral infection were compared to a control group of mice that continued to consume a standard chow diet. 
The ketogenic mice group had an increased survival rate and maintained a higher blood oxygen saturation level as compared to the standard chow group. The researchers concluded the ketogenic diet protected against the flu virus by activating immune cells that protect the lungs and epithelial cells within the airway, thus enhancing antiviral resistance.
“Therefore, KD-mediated immune-metabolic integration represents a viable avenue toward preventing or alleviating influenza disease.”
Mechanism of Action (In-depth Science Review)
γδ T cells are a subset of T cells that play a key role in the recognition of lipid antigens. While many details about these specific T-cells are still unknown, it is known that they may act as a bridge between the innate and adaptive immune responses. γδ T cells are unique in that they do not appear to require MHC presentation and the specific antigen that triggers their activation is widely unknown; although, some studies have shown MHC class 1b recognition.
After the research team found increased antiviral resistance in the ketogenic fed mice, they performed a transcriptome analysis of the influenza virus-infected lung tissue. While the ketogenic diet group did not show increased interferon count or interferon-stimulated genes, IPA revealed increased T cell pathway activation, indicated the immune protection was mediated through nonconventional mechanisms.
The researchers investigated further and found that of the top regulated genes in the ketogenic diet mice, γδ T cells and 4 genes (Cxcr6, Blk, Cd163l1, and Ccr4) highly associated with γδ T cells were identified. Flow cytometry revealed no other cellular differences between the ketogenic and chow-fed mice, indicating the γδ T cells activation was largely responsible for the protective effects. This data suggests that following a ketogenic diet may improve or prevent influenza infection.
Have You Noticed a Difference During Flu Season?
Do you get less sick when you’re on the ketogenic diet? Are all of your friends coming down with the flu while you stay healthy? Let us know in the comments below!
Emily L. Goldberg, Ryan D. Molony, Eriko Kudo, Sviatoslav Sidorov, Yong Kong, Vishwa Deep Dixit, Akiko Iwasaki. Ketogenic diet activates protective γδ T cell responses against influenza virus infection. Science Immunology 15 Nov 2019: Vol. 4, Issue 41, eaav2026. DOI: 10.1126/sciimmunol.aav2026.
Chelsea Malone works as a researcher in the field of health and performance supplementation. She contributes science-based articles and information to Ketogenic.com. She received her Bachelor of Science in Biomedical Sciences from the University of Central Florida and her Master of Science in Medical Sciences from the University of South Florida. Her specialties are in biochemistry, immunology, and pathophysiology. In her free time, she enjoys cooking, traveling, hiking, and reading.