A ketogenic drink improves cognition in mild cognitive impairment: Results of a 6‐month RCT

Abstract Introduction Counteracting impaired brain glucose metabolism with ketones may improve cognition in mild cognitive impairment (MCI). Methods Cognition, plasma ketone response, and metabolic profile were assessed before and 6 months after supplementation with a ketogenic drink containing medium chain triglyceride (ketogenic medium chain triglyceride [kMCT]; 15 g twice/day; n = 39) or placebo (n = 44). Results Free and cued recall (Trial 1; P = .047), verbal fluency (categories; P = .024), Boston Naming Test (total correct answers; P = .033), and the Trail‐Making Test (total errors; P = .017) improved significantly in the kMCT group compared to placebo (analysis of covariance; pre‐intervention score, sex, age, education, and apolipoprotein E4 as covariates). Some cognitive outcomes also correlated positively with plasma ketones. Plasma metabolic profile and ketone response were unchanged. Conclusions This kMCT drink improved cognitive outcomes in MCI, at least in part by increasing blood ketone level. These data support further assessment of MCI progression to Alzheimer's disease.