What Is This Study About?
In a state of ketosis, the brain uses more ketones and less glucose. This “metabolic switch” may improve cognitive function and reduce the risk of neurodegeneration. Here, researchers examined the effects of a ketogenic diet on Alzheimer’s disease risk factors.
How was this Study Conducted?
In this study, researchers put 20 older adults with mental impairments on two diets: a modified Mediterranean-ketogenic diet and a low-fat diet. The study used a randomized crossover design, so all participants ate both diets in separate trials. At baseline and after 6 weeks, researchers measured ketone levels, cerebrospinal fluid (CSF), cerebral perfusion (brain blood flow), and brain ketone utilization.
Study Results
Compared to the low-fat group, the keto group had increased blood-ketone levels, cerebrospinal fluid, cerebral perfusion, and ketone uptake in the brain—all positive changes in Alzheimer’s risk. Interestingly, both groups improved on a memory test, though the researchers believe this could be due to practice effects.
Conclusions and Insights
Perhaps the most important finding was the increase in cerebrospinal fluid (CSF) among keto dieters. During deep sleep, CSF helps flush the brain of amyloid beta and tao—two proteins linked to the development of Alzheimer’s. Ketones, the researchers believe, may also block amyloid beta from entering brain cells. More research is needed, however, before recommending the ketogenic diet as Alzheimer’s therapy.