Everstack Evidence

Keto BHB (beta-hydroxybutyrate salts): ketones, brain energy and what the human evidence shows

Grade D for BHB salts specifically. Salts reliably raise blood BHB, but only modestly (about 1 mM in Stubbs 2017, versus about 2.8 mM for a ketone ester at a similar dose), and we found no long-term randomized trial of BHB salts on brain energy or cognition in older adults, MCI or Alzheimer's disease. The one salt cognition trial we found was null (Waldman 2018). The stronger brain evidence is for ketogenic MCT drinks (6-month RCT in MCI, PET studies, a meta-analysis), which we would grade C to B for that use, and for ketone esters, whose small trials are pooled in a 2026 meta-analysis showing a modest cognitive benefit. We do not transfer those results to salts.

Published 2026-10-15Sources checked 2026-10-1513 sourcesEverstack research teamHow we work

Editorial section. Research summaries are not product claims and contain no product links or offers. A summary is never proof that any product works.

The question

Do BHB salt supplements raise blood ketones, and is there human evidence that they support brain energy or cognition, compared with ketone esters and MCT oil?

Study design

Salts: a randomized metabolic study comparing sodium plus potassium BHB salts with a ketone monoester in healthy adults (Stubbs 2017); a crossover trial of 11.38 g of BHB salt before exercise and a cognitive task in 15 young men (Waldman 2018); a crossover trial of 0.3 g/kg salts before cycling in 10 men (O'Malley 2017); a 90-day safety trial in 22 adolescents (Stefan 2021). Esters and all exogenous ketones: a 28-day ketone monoester safety study in 24 adults (Soto-Mota 2019) and a 2026 meta-analysis of 38 randomized studies of exogenous ketones and cognition (Bonnechère 2026). MCT: a 6-month RCT of a ketogenic MCT drink in 83 adults with MCI (Fortier 2021), a PET study in Alzheimer's disease (Croteau 2018), a 90-day RCT in 152 people with Alzheimer's disease (Henderson 2009) and a meta-analysis of 12 MCT studies (Avgerinos 2020). Background: reviews of brain ketone uptake in aging (Cunnane 2016, 2020) and a meta-analysis of ketone supplements and exercise (Valenzuela 2020). ^{[1][2][3][4][5][6][7][8][9][10][11][12][13]}

What they found

The aging brain takes up less glucose, but its ketone uptake looks preserved, and in Alzheimer's disease brain ketone use rose in direct proportion to blood ketones when people took MCT (Croteau 2018). In MCI, 15 g of ketogenic MCT twice a day for 6 months improved several memory, language and attention tests versus placebo (Fortier 2021); MCT in Alzheimer's disease gave a short-term ADAS-Cog benefit, mostly in people without APOE4 (Henderson 2009), and pooled MCT data show mild ketosis and a small cognitive signal (Avgerinos 2020). Across exogenous ketones, the 2026 meta-analysis found a modest improvement in cognition (SMD 0.29), with no clear difference by formulation, and a higher dose linked to a larger effect. For salts: blood BHB rose to about 1 mM, much lower than with an ester, partly because many salts contain the L form that the body uses less well (Stubbs 2017). In young men, salts did not improve cognitive or sprint performance (Waldman 2018), increased fat burning but lowered time-trial power by about 7% (O'Malley 2017), and pooled trials show no exercise benefit for salts or esters (Valenzuela 2020). ^{[1][2][3][4][5][6][7][8][9][10][11][12][13]}

Limitations

The brain trials with real duration used MCT drinks or ketone esters, not BHB salts. Salt trials are small, short (single doses or up to 90 days) and done mostly in young healthy people. The 2026 meta-analysis pooled many formulations and short tests, and we have not yet reviewed its funding and disclosure statements; Fortier 2021 and Henderson 2009 had industry links to the products tested. Henderson 2009's benefit faded by day 90 in the full group. Exercise results from salts are mixed to negative.

What this does not mean

None of this shows that BHB salts are a treatment for MCI, Alzheimer's disease, epilepsy or any disease, and we make no weight-loss or fat-loss claim. Our claims are structure/function only: supports blood ketone levels, and supports brain energy metabolism as an alternative fuel. Cautions: a serving of BHB salts can carry a large dose of sodium, plus potassium, calcium or magnesium, so people with high blood pressure, heart failure or kidney disease, or on a low-sodium diet or blood pressure drugs, should ask a clinician first. Stomach upset and diarrhea are common at higher doses. Ketones can lower blood glucose, so people taking glucose-lowering drugs should ask first. Not for pregnancy, breastfeeding or children.

Sources

1. Stubbs BJ et al. Front Physiol. 2017;8:848. doi.org/10.3389/fphys.2017.00848
2. Waldman HS et al. Appl Physiol Nutr Metab. 2018;43(7):711-717. doi.org/10.1139/apnm-2017-0724
3. O'Malley T et al. Appl Physiol Nutr Metab. 2017;42(10):1031-1035. doi.org/10.1139/apnm-2016-0641
4. Stefan M et al. Nutrients. 2021;13(3):854. doi.org/10.3390/nu13030854
5. Bonnechère B et al. Front Nutr. 2026;13:1802531. doi.org/10.3389/fnut.2026.1802531
6. Soto-Mota A et al. Regul Toxicol Pharmacol. 2019;109:104506. doi.org/10.1016/j.yrtph.2019.104506
7. Fortier M et al. Alzheimers Dement. 2021;17(3):543-552. doi.org/10.1002/alz.12206
8. Croteau E et al. J Alzheimers Dis. 2018;64(2):551-561. doi.org/10.3233/jad-180202
9. Henderson ST et al. Nutr Metab (Lond). 2009;6:31. doi.org/10.1186/1743-7075-6-31
10. Avgerinos KI et al. Ageing Res Rev. 2020;58:101001. doi.org/10.1016/j.arr.2019.101001
11. Cunnane SC et al. Front Mol Neurosci. 2016;9:53. doi.org/10.3389/fnmol.2016.00053
12. Cunnane SC et al. Nat Rev Drug Discov. 2020;19(9):609-633. doi.org/10.1038/s41573-020-0072-x
13. Valenzuela PL et al. Int J Sports Physiol Perform. 2020;15(3):298-308. doi.org/10.1123/ijspp.2019-0918

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