Caffeine intake increases plasma ketones: an acute metabolic study in humans

Can J Physiol Pharmacol. 2017 Apr;95(4):455-458. doi: 10.1139/cjpp-2016-0338. Epub 2016 Nov 25.


Brain glucose uptake declines during aging and is significantly impaired in Alzheimer's disease. Ketones are the main alternative brain fuel to glucose so they represent a potential approach to compensate for the brain glucose reduction. Caffeine is of interest as a potential ketogenic agent owing to its actions on lipolysis and lipid oxidation but whether it is ketogenic in humans is unknown. This study aimed to evaluate the acute ketogenic effect of 2 doses of caffeine (2.5; 5.0 mg/kg) in 10 healthy adults. Caffeine given at breakfast significantly stimulated ketone production in a dose-dependent manner (+88%; +116%) and also raised plasma free fatty acids. Whether caffeine has long-term ketogenic effects or could enhance the ketogenic effect of medium chain triglycerides remains to be determined.

Keywords: Alzheimer’s disease; acides gras libres; caffeine; caféine; cétones; cétonémie; free fatty acids; ketonemia; ketones; lipolyse; lipolysis; maladie d’Alzheimer; medium chain triglycerides; triglycérides à chaîne moyenne.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aging / metabolism*
  • Alzheimer Disease / metabolism
  • Brain / metabolism*
  • Caffeine / administration & dosage
  • Caffeine / blood
  • Caffeine / pharmacology*
  • Dietary Supplements
  • Dose-Response Relationship, Drug
  • Energy Metabolism / drug effects
  • Fatty Acids, Nonesterified / blood*
  • Female
  • Glucose / metabolism
  • Healthy Volunteers
  • Humans
  • Ketones / blood
  • Ketones / metabolism*
  • Lipid Metabolism / drug effects
  • Male
  • Middle Aged
  • Oxidation-Reduction / drug effects
  • Purinergic P1 Receptor Antagonists / administration & dosage
  • Purinergic P1 Receptor Antagonists / blood
  • Purinergic P1 Receptor Antagonists / pharmacology*
  • Young Adult


  • Fatty Acids, Nonesterified
  • Ketones
  • Purinergic P1 Receptor Antagonists
  • Caffeine
  • Glucose