Glucose has long been considered the brain’s primary fuel, but ketone bodies may offer critical support, especially during periods of low carbohydrate availability. A recent study found that a ketogenic diet boosted levels of brain-derived neurotrophic factor (BDNF)—a key protein that supports brain health—by 47%, highlighting the diet’s potential to support brain health even in people without cognitive impairment.

Researchers recruited 11 healthy but overweight adults to participate in a randomized, crossover study. Each participant followed two different diets: a ketogenic diet high in fat and low in carbohydrates, and a standard balanced diet. Each diet lasted three weeks and ended with brain imaging scans (using MRI and PET) and blood tests to measure brain blood flow and BDNF levels.

They found that the ketogenic diet markedly increased ketone levels in the blood compared to the standard diet. Brain blood flow rose by 22% after eating the ketogenic diet, and BDNF levels increased by 47%. Researchers also found a strong link between ketone levels in the blood and higher brain blood flow.

This was a small study, but the findings suggest that a ketogenic diet enhances brain blood flow and boosts vital brain-supporting proteins, even in people without memory loss. This opens up new possibilities for using ketogenic nutrition as a strategy to preserve cognitive function and support long-term brain health. Learn how to plan the optimal ketogenic diet in this clip featuring Dr. Dominic D'Agostino.