A 3-Week Ketogenic Diet Increases Global Cerebral Blood Flow and Brain-Derived Neurotrophic Factor.
Level 2 - randomized trial
Individual randomized crossover trial
PubMed 40172923 · doi:10.1210/clinem/dgaf207
What was done
Eleven cognitively healthy individuals with overweight participated in a randomized crossover trial comparing a 3-week ketogenic diet to a 3-week standard diet. At the end of each diet period, participants underwent blood sampling for basal plasma beta-hydroxybutyrate and brain-derived neurotrophic factor, alongside [15O]H2O PET co-registered with MRI to quantify global cerebral blood flow.
What was found
Compared to the standard diet, the ketogenic diet increased basal plasma beta-hydroxybutyrate levels (647 [418-724] vs 50 [50-60] µmol/L, P < .05), elevated cerebral blood flow by 22% (P = .02), and increased brain-derived neurotrophic factor by 47% (P = .04). Beta-hydroxybutyrate levels correlated significantly with cerebral blood flow across both diets (R2 = 0.54, P < .001).
Why it matters
This study demonstrates in humans that short-term dietary ketosis increases global cerebral perfusion and circulating neurotrophic factor levels, supporting further investigation of ketogenic diets for conditions associated with cerebral hypoperfusion.
Limits
The sample size was very small (n = 11) and the intervention was short (3 weeks). The study was conducted in cognitively healthy individuals with overweight, meaning results may not generalize to clinical populations with cognitive impairment, and cognitive function itself was not evaluated.
Cited by
- partial Beta-hydroxybutyrate increases brain GABA levels, elevates BDNF, and reduces cellular oxidation.