Source: PubMed / NCBI · human studies preferred · ranked by evidence qualityLast analyzed: May 26, 2026
⚫Insufficient Evidence
20 studies·4 RCTs·15 reviews
The summary below was generated by an AI system (Claude) based on the studies listed. It is a synthesis tool, not a clinical opinion. Read individual studies for full context.
Exogenous ketones — typically consumed as ketone esters or salts — have attracted growing research interest across several health domains including metabolic disease, cognitive function, cardiovascular health, and athletic performance. The available evidence base includes a mix of randomized controlled trials (RCTs) and narrative reviews, covering populations ranging from people with type 2 diabetes and heart failure with preserved ejection fraction (HFpEF) to women with polycystic ovary syndrome (PCOS) and individuals with mild cognitive impairment. While the breadth of potential applications is notable, the overall body of evidence remains early-stage, with most human trials being small, short-duration, and exploratory in nature.
Key findings
✓A 6-month RCT found that a ketogenic drink improved cognition in individuals with mild cognitive impairment, suggesting a potential role for exogenous ketones in early neurodegenerative conditions.
✓A crossover RCT in heart failure patients with preserved ejection fraction (HFpEF) examined exogenous ketones on cardiometabolic endpoints, reflecting interest in ketones as an alternative fuel source for the failing heart.
✓An RCT in women with PCOS found that ketone supplementation acutely lowered androgen and glucose levels, pointing to short-term hormonal and metabolic effects in this population.
✓Review literature supports the concept that ketone bodies — particularly beta-hydroxybutyrate — can serve as an alternative brain fuel and may have neuroprotective properties relevant to brain injury and neurodegenerative disease.
✓A weight-maintaining ketogenic diet RCT in obese adults with type 2 diabetes suggests potential benefits for glycemic control and insulin sensitivity, though the independent contribution of exogenous ketones versus dietary carbohydrate restriction is difficult to separate.
Evidence gaps
?Most human RCTs are small and short in duration, making it impossible to draw conclusions about long-term safety, efficacy, or optimal dosing of exogenous ketone supplements across any population.
?It remains unclear how much of the observed benefit in metabolic and cognitive outcomes is attributable to exogenous ketones specifically versus broader dietary or lifestyle changes such as carbohydrate restriction.
?Evidence on safety and efficacy across diverse populations — including older adults, people with type 1 diabetes, and critically ill patients — is sparse and largely based on reviews rather than controlled trials.
Safety summary
Exogenous ketones appear to be generally well-tolerated in short-term studies, but comprehensive long-term safety data in humans are lacking. Gastrointestinal discomfort is a commonly noted concern with ketone ester formulations, and caution is warranted in populations at risk for ketoacidosis, such as those with type 1 diabetes.
Studies (20)
Effects of Exogenous Ketone Supplementation on Blood Glucose: A Systematic Review and Meta-analysis.
Advances in nutrition (Bethesda, Md.) · 2022 · Falkenhain K et al.
Meta-Analysis🟢
Key finding
Effects of Exogenous Ketone Supplementation on Blood Glucose: A Systematic Review and Meta-analysis.
A ketogenic drink improves cognition in mild cognitive impairment: Results of a 6-month RCT.
Alzheimer's & dementia : the journal of the Alzheimer's Association · 2021 · Fortier M et al.
RCT🟡
Key finding
A ketogenic drink improves cognition in mild cognitive impairment: Results of a 6-month RCT.
Funded by: Industry (inferred from affiliations)
COI: Stephen C. Cunnane has consulted for or received travel honoraria or test products for research from Nestlé Health Science, Bulletproof, Cerecin, and Abitec. Stephen C. Cunnane is the founder and director of the consulting company, Senotec Ltd. JPG is an employee of the
Société des Produits Nestlé S.A. There are no other conflicts to report.
COI: Funding Support and Author Disclosures Supported by the Doris Duke Charitable Foundation (#2020061, to Dr Selvaraj), the Measey Foundation (to Dr Selvaraj), the Penn Metabolic Tracer Resource (to Dr Zamani), and the UPenn Institute for Translational Medicine and Therapeutics (to Drs Selvaraj and Zamani). The project was also supported by the National Center for Advancing Translational Sciences, National Institutes of Health (NIH) grant UL1 TR001878, and by the National Institute of Diabetes and Digestive and Kidney Diseases, NIH grant P30 DK19525. Research reported in this publication was supported by the National Center for Advancing Translational Sciences of the NIH Award Number UL1TR001878. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. Supported in part by the Institute for Translational Medicine and Therapeutics’ (ITMAT) Transdisciplinary Program in Translational Medicine and Therapeutics. Dr Selvaraj has received related research support from the National Heart, Lung, and Blood Institute (K23 HL161348), Doris Duke Charitable Foundation (#2020061), American Heart Association (#935275), the Measey Foundation, the Mandel Foundation, Duke Heart Center Leadership Council, the Institute for Translational Medicine and Therapeutics, and Foundation for Sarcoidosis Research; and has consulted for AstraZeneca and BridgeBio for unrelated work. Dr Chirinos is supported by NIH grants R01-HL 121510, U01-TR003734, 3U01TR003734-01W1, U01-HL160277, R33-HL-146390, R01-HL153646, K24-AG070459, R01-AG058969, R01-HL104106, P01-HL094307, R03-HL146874, R56-HL136730, R01 HL155599, R01 HL157264, R01HL155, and 1R01HL153646-01; has recently consulted for Bayer, Sanifit, Fukuda-Denshi, Bristol Myers Squibb, Johnson and Johnson, Edwards Life Sciences, Merck, Biohaven, the University of Delaware, Emory University, and the Galway-Mayo Institute of Technology; has received University of Pennsylvania research grants from the NIH, Fukuda-Denshi, Bristol Myers Squibb, Microsoft, and Abbott; is named as an inventor in a University of Pennsylvania patent for the use of inorganic nitrates/nitrites in HFpEF; is named as inventor on patent applications for the use of protein biomarkers in heart failure; and has received research device loans from Atcor Medical, Fukuda-Denshi, Uscom, NDD Medical Technologies, Microsoft, and MicroVision Medical. Dr Kelly is supported by NIH R01 HL151345, R01 HL128349, and R01 HL058493; and serves on scientific advisory boards for Amgen and Pfizer. Dr Zamani is supported by R01 HL167753, R01 HL155599, R01 HL157264, UH3 DK128298, and U01 HL160277; has received research support from Amgen; and has consulted for Pfizer and Vyaire. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
Biochemical Society transactions · 2020 · Soto-Mota A et al.
Review🟡
Key finding
Why a d-β-hydroxybutyrate monoester?
COI: The intellectual property covering the uses of ketone bodies and ketone esters are owned by BTG Plc, Oxford University Innovation Ltd and the US National Institutes of Health. Professor Kieran Clarke, as an inventor, will receive a share of the royalties under the terms prescribed by each institution. Professor Clarke is a director of TdeltaS Ltd, a company spun out of the University of Oxford to develop products based on the science of ketone bodies in human nutrition. The other authors declare that they have no competing financial interests or personal relationships that could have influenced the work reported in this paper.
Exogenous ketone supplementation: an emerging tool for physiologists with potential as a metabolic therapy.
Experimental physiology · 2023 · Falkenhain K et al.
Review🟡
Key finding
Exogenous ketone supplementation: an emerging tool for physiologists with potential as a metabolic therapy.
Funded by: CIHR
COI: J.P.L. is volunteer Chief Scientific Officer for the Institute for Personalized Therapeutic Nutrition, a registered charity in Canada. He holds founder shares in Metabolic Insights Inc., a for‐profit company that developed non‐invasive metabolic monitoring devices.