Ketone Ester Effects on Biomarkers of Brain Metabolism and Cognitive Performance in Cognitively Intact Adults ≥ 55 Years Old. A Study Protocol for a Double-Blinded Randomized Controlled Clinical Trial

This paper describes the protocol for a double-blinded randomized placebo-controlled trial at a clinical unit in Baltimore, US, in 50 cognitively intact adults aged 55 or older with metabolic syndrome. Participants will drink 25 g of ketone monoester or an isocaloric placebo three times daily for 28 days. The primary outcome is precuneus beta-hydroxybutyrate concentration measured by magnetic resonance spectroscopy, with exploratory outcomes including cognition, plasma and urine BHB, Alzheimer's disease biomarkers, and stool microbiome.