Hydroxycitrate

Hydroxycitrate refers to the salts and esters of hydroxycitric acid (HCA), a naturally occurring compound most notably found in Garcinia cambogia and other Garcinia species. The name is typically used for the deprotonated form present in dietary supplements, such as calcium hydroxycitrate. HCA is a derivative of citric acid and is used in research and commercial products marketed for weight management.

Biochemical action and mechanism: In biochemical studies, hydroxycitrate inhibits ATP citrate lyase (ACLY), an enzyme that converts citrate to acetyl-CoA in the cytosol for fatty acid and cholesterol synthesis. By limiting cytosolic acetyl-CoA availability, it is proposed to reduce de novo lipogenesis and potentially influence energy balance. The magnitude of this effect in humans at commonly used supplement doses remains uncertain.

Clinical use and evidence: HCA-containing products are marketed as weight-management supplements. Randomized trials have produced mixed results, with some showing small effects on weight loss and others finding no meaningful benefit beyond placebo. Meta-analyses generally report limited and inconsistent efficacy, and study quality varies. Reported effects on appetite are not consistently observed.

Safety, regulation, and cautions: HCA is not approved as a drug for obesity or metabolic disease. Safety data are incomplete, and adverse effects commonly reported include digestive upset and headaches. There have been case reports and regulatory warnings related to liver injury in association with Garcinia cambogia–containing products, though causal links remain debated. People with liver disease, pregnant or lactating individuals, or those taking anticoagulants, diabetes medications, or other therapies should exercise caution and consult a clinician before use.

Source notes: In nature, HCA occurs in free form and as salts or esters; Garcinia cambogia is a traditional source. Purified hydroxycitrate is used in supplements and as a research reagent, with attention to quality and purity due to contamination concerns.