A rind extract from a Southeast Asian fruit, standardised to hydroxycitric acid. It became one of the best-selling weight-loss supplements in the world on the back of television promotion rather than trial data.
The largest and best-designed trial of garcinia — a 12-week randomised study in 135 people — found no difference in weight or fat mass against placebo. Meta-analyses since report an average difference of under a kilogram, within the range attributable to bias in small trials. Set against that near-absent benefit are repeated case reports of acute liver failure, including cases requiring transplantation, and the fact that weight-loss botanicals are the category most often adulterated with undeclared pharmaceuticals.
Regulation: Sold in the US as a dietary supplement with no pre-market efficacy or safety review. Weight-loss products in this category have repeatedly been recalled for containing undeclared prescription drugs such as sibutramine, which was withdrawn from markets for cardiovascular risk.
What the research used
The amounts, forms and durations published trials of Garcinia cambogia actually administered.
These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.
These doses are what trials administered; the trials themselves largely found no meaningful weight difference. Many retail products are blends where garcinia is one of several stimulant or laxative ingredients.
This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.
When it was taken
Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.
None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.
⏳On an empty stomach
Not enough
Product instructions commonly specify 30 to 60 minutes before meals, on the reasoning that hydroxycitric acid should act on the meal. No trial compared this against other schedules.
Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.
The evidence in depth
Best supported: Not enough
What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.
Evidence is limited for garcinia and weight loss. The largest well-controlled trial found no difference from placebo, and pooled estimates average under a kilogram — small enough to be explained by bias in the smaller studies.
What may be going on: Hydroxycitric acid inhibits ATP-citrate lyase in laboratory models, which was proposed to reduce fat synthesis.
Not enough evidence. Not enough human research to say anything useful yet.
Deep research mode adds each paper’s own conclusion and stated limitations.
Things to know
Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.
Worth knowing
Acute liver failure has been reported
Multiple published cases describe hepatitis and acute liver failure associated with garcinia-containing products, some requiring liver transplantation and some fatal. A widely publicised multi-ingredient product containing garcinia was withdrawn after a cluster of hepatitis cases.
Worth knowing
Adulteration with undeclared drugs
Weight-loss botanicals are the most frequently adulterated supplement category. Products have been found containing sibutramine, phenolphthalein, laxatives and diuretics that are not on the label, some of them withdrawn drugs.
Interaction
Serotonergic drugs and mania
Interacts withSSRIs, SNRIs, other serotonergic drugs
Case reports describe serotonin toxicity and manic episodes in people taking garcinia with antidepressants. Its proposed serotonergic activity makes that combination inadvisable.
Avoid
Pregnancy, breastfeeding and existing liver disease
It should not be used in pregnancy or breastfeeding, or by anyone with liver disease, and rhabdomyolysis has also been reported in isolated cases.
Interaction
Glucose-lowering medication
Interacts withInsulin, sulfonylureas
Garcinia has been reported to lower blood glucose, which can add to insulin or oral antidiabetic drugs.