← All supplements
Limited evidenceHeart & metabolic

Black Garlic

Garlic slowly heat-aged until it turns dark and sweet, sold for cholesterol and antioxidant effects. Human trials are few and mostly small or uncontrolled; the broader garlic literature is stronger than the black garlic literature specifically.

Where to buy

View on iHerb

Ships to 180+ countries · welcome discount for new customers

Referral link — this site may earn a commission on purchases.

What the science says

  • Lipid profile Limited evidence

    A randomized triple-blind trial of aged black garlic in grade I hypertension found shifts in lipoprotein subclass composition rather than clear reductions in standard cholesterol values. A separate before-and-after study in hypercholesterolaemic subjects reported lipid changes but had no control group.

  • Endothelial function Limited evidence

    The same before-and-after study reported improved endothelial measures after black garlic consumption. Without randomisation or a placebo arm, the result cannot be separated from diet and seasonal variation.

  • Cardiovascular risk factors from garlic generally Moderate evidence

    An updated systematic review and meta-analysis of randomized trials found garlic supplementation modestly improves blood pressure and some lipid markers in adults. Those trials mostly used powdered or aged garlic, not black garlic, so the finding transfers only loosely.

Dosage & safety

Studied doseHuman studies used roughly 2–6 g of black garlic daily (about 1–2 cloves) or 250–1000 mg of concentrated extract, for 6–12 weeks.
SafetyA food, generally very well tolerated and much gentler on the stomach than raw garlic. Aging reduces allicin, so the antiplatelet effect is likely smaller, but caution with anticoagulants is still sensible before surgery. It is higher in sugars than raw garlic.

How to take it

TimingTiming does not matter.
With food?With or without food; black garlic is far gentler on the stomach than raw garlic.
Worth knowingAgeing destroys most of the allicin, so if you are taking garlic specifically for its cardiovascular effects, aged black garlic is not interchangeable with a raw or allicin-standardised product.

Interactions

With medications

  • warfarin and other anticoagulants or antiplatelet drugs

    Garlic preparations can affect platelet function, though ageing reduces the allicin responsible. tell your doctor, and stop concentrated extracts 7 to 10 days before surgery

With other supplements

  • fish oil, ginkgo and other antiplatelet supplements

    Additive effect on platelet function. avoid stacking several before surgery or if you bruise easily

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does black garlic lower cholesterol?

Evidence that black garlic lowers cholesterol is limited: a randomized trial found shifts in lipoprotein subclasses rather than clear drops in standard cholesterol values, and another study had no control group. Ordinary garlic supplements have moderate evidence for modest lipid and blood pressure effects, but that transfers only loosely to black garlic.

Is black garlic as good as regular garlic for heart health?

Black garlic is not interchangeable with raw or allicin-standardised garlic, because ageing destroys most of the allicin. The stronger cardiovascular evidence for garlic comes mostly from powdered or aged garlic trials, not black garlic.

How much black garlic should I eat per day?

Human studies of black garlic used roughly 2–6 g daily, about 1–2 cloves, or 250–1000 mg of concentrated extract, for 6–12 weeks. Timing does not matter and it can be taken with or without food.

Is black garlic safe with blood thinners?

Black garlic likely has a smaller antiplatelet effect than raw garlic because ageing reduces allicin, but caution with warfarin and other anticoagulants is still sensible. Tell your doctor, and stop concentrated black garlic extracts 7 to 10 days before surgery.

Scientific references

Related in Heart & metabolic

Herbal medicines: what the evidence says (335)