Ketone fuel
β-Hydroxybutyrate
Also searched as β-Hydroxybutyrate.
You want it available: rising β-hydroxybutyrate is the signature of a fasted state, and it quiets the NLRP3 inflammasome.
In depth
The ketone body the liver makes when glucose runs low — an alternative fuel that doubles as an anti-inflammatory signaling molecule.
What drives it
Fasting response increases it.
Youm 2015, Nat Med 21:263 — β-hydroxybutyrate levels are elevated by starvation, caloric restriction, and the ketogenic diet as an alternative fuel. doi:10.1038/nm.3804. A threshold, not a gradient — and it is the most actionable number on this row: energy restriction for 10 to 14 hours OR more depletes liver glycogen and triggers hydrolysis of triglycerides to free fatty acids in adipocytes. Those FFAs travel to hepatocytes and are converted to the ketone bodies ACETOACETATE and beta-hydroxybutyrate. Below roughly ten hours the liver is still running on glycogen and this edge carries no flux. The same FFAs also activate PPAR-alpha. doi 10.1038/nm.3804.
Training load increases it.
10.7554/eLife.15092 — mouse hippocampus, 30 days voluntary wheel running. doi 10.7554/eLife.15092
Fat burning increases it.
Ketone bodies are made from acetyl-CoA derived from fatty-acid oxidation. Carried by the intermediary-metabolism, micronutrient and clinical reviews. doi 10.3390/nu18132141 · PMC9967593
Ketone production increases it.
10.3390/vetsci7030095 — Nbk560564 — the other disposal route, and the one that actually removes fat from the body. 'Die aus der enzymatischen Spaltung entstandenen Fettsäuren werden in das Blut abgegeben. Sie können von der Muskulatur zur beta-oxidation oder von der Leber zur KETOGENESE aufgenommen und verstoffwechselt werden' = the fatty acids from lipolysis enter the blood and can be taken up by muscle for beta-oxidation or by the liver for ketogenesis (DocCheck Flexikon — Lipolyze (deutsch)). ⇒ released fat has exactly two honest exits — burned in muscle, OR converted to ketones in the liver. Everything else is recapture. A release agent with neither exit open is moving fat around, not removing it. doi 10.3390/vetsci7030095
What it drives
It reduces Inflammatory alarm.
Youm 2015, Nat Med 21:263 — the ketone β-hydroxybutyrate suppresses NLRP3 inflammasome activation (blocking K+ efflux and ASC oligomerization), linking fasting to reduced inflammation. doi 10.1038/nm.3804
It increases Supports BDNF signaling.
Sleiman 2016 (eLife, PMC4915811) — β-hydroxybutyrate, which rises after prolonged exercise, induces BDNF promoter activity (notably the activity-dependent promoter I) by inhibiting HDAC2 and HDAC3; ventricular BHB raised hippocampal BDNF and increased TrkB-dependent neurotransmitter release. Replicated in hippocampal neurons (PMID 29966721). Mechanism is HDAC2/HDAC3 inhibition at selective BDNF promoters. Mouse; includes intraventricular administration. PMID 29966721 · PMC4915811
It reduces DNA methylation.
And an endogenous HDAC inhibitor - which is why fasting and ketogenic states produce effects fuel substitution alone would not explain. Carried by the intermediary-metabolism, micronutrient and clinical reviews. doi 10.3390/nu18132141 · PMC9967593
It increases Memory & focus.
An alternative cerebral fuel when glucose availability falls. Carried by the intermediary-metabolism, micronutrient and clinical reviews. doi 10.3390/nu18132141 · PMC9967593
It increases Curbs appetite.
Ketosis suppresses appetite independently of caloric intake. Carried by the intermediary-metabolism, micronutrient and clinical reviews. doi 10.3390/nu18132141 · PMC9967593
It increases Cellular cleanup.
Verbatim: 'D-BHB exposure to cultured astrocytes elevates the conjugated form of microtubule-associated protein 1A/1B-light chain 3 (LC3-II) levels, increases the number of autophagosomes, and reduces sequestosome-1 (SQSTM1/p62) protein content.' (10.1007/s12035-026-05852-6). What was measured: Autophagy flux markers in primary cultured astrocytes: LC3-II conjugation by immunoblot, autophagosome counts, SQSTM1/p62 degradation; plus AMPK and ULK1 phosphorylation. doi 10.1007/s12035-026-05852-6
It increases Mitochondrial energy.
Verbatim: 'βHB treatment increased β-cell survival and proliferation, while also increasing mitochondrial mass, respiration and adenosine triphosphate (ATP) production.' (10.4102/jir.v2i1.25). Scope (cell study): pancreatic beta-cells in culture · medium exposure · concentration not stated in the retrieved abstract · n not stated · in vitro experiment, Journal of Metabolic Health 2017. doi 10.4102/jir.v2i1.25
It increases Longevity gene.
Verbatim: 'BHBA significantly improved water maze performance; increased the ACh content, SOD activity, and SIRT1 expression; and decreased AChE and LDH activity, ROS, MDA, IL-1β, TNF-α contents, and NLRP3 expression.' (DOI 10.3389/fphar.2021.751028). What was measured: SIRT1 expression in hippocampus / HT22 cells (measured alongside water maze performance, ACh, SOD, AChE, LDH, ROS, MDA, IL-1β, TNF-α, NLRP3), in D-galactose-injured mice. doi 10.3389/fphar.2021.751028
It increases Cellular fuel.
The metabolic ratios lactate/pyruvate and β-hydroxybutyrate/acetoacetate are considered valuable tools to evaluate the in vivo redox cellular state by estimating the free NAD+/NADH in cytoplasm and…. PMC8125771
It increases Niacin receptor.
Beta-hydroxybutyrate is the endogenous agonist of GPR109A/HCAR2. doi 10.1002/advs.202003410
Blends that modulate it
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See it on the map
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