Clay, Soap & Other

Black Garlic

Allium sativum

B Limited clinical evidence

In one small trial, black garlic extract slightly lowered diastolic blood pressure; cholesterol results are inconsistent. Take care with blood thinners.

Heart & Circulation
Black Garlic
PregnancyCaution
BreastfeedingCaution
ChildrenUnknown
Drug interactionsInteraction reported
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On this page

At a glance

Black garlic is made by keeping fresh garlic at controlled heat and humidity for weeks; the cloves turn black, soft and sweetish. In a study of 67 people with moderately high cholesterol, its extract slightly lowered diastolic blood pressure but did not significantly change cholesterol. The evidence is limited.

Parts used: bulb (cloves)
Key constituents: S-allyl cysteine (SAC), Polyphenols, Melanoidins

Updated: October 24, 2026

Sources and research limitations appear below. The existence of a source does not mean every use has been clinically verified.

What is it used for?

  • B Limited clinical evidence

    Limited clinical evidence: Limited human data; small samples, methodological problems or inconsistent results reduce certainty. Findings do not apply to every product.

    How do we rate evidence levels? →

    In a randomized, placebo-controlled crossover trial in 67 adults with moderately high cholesterol, 250 mg of aged black garlic extract daily lowered diastolic blood pressure by about 3.7 mmHg after 6 weeks; systolic pressure and cholesterol values did not change significantly. In an uncontrolled 12-week study where people ate 12 g of black garlic a day, lipid values also did not change in the high-cholesterol group. [2][3]

How is it used?

Food

Black garlic is eaten as food; one study used about 4 cloves (12 g) a day. There is no verified dose for extract supplements.

[3][2]

Safety & interactions

  • If you take blood thinners or aspirin, ask your doctor before using a black garlic supplement; garlic supplements may increase bleeding risk.
  • Tell your doctor before surgery if you take garlic supplements.
  • Garlic in amounts above food may not be safe in pregnancy or breastfeeding; do not use supplements.
  • People allergic to garlic should also avoid black garlic.
  • Black garlic studies are small and mostly industry-funded; do not stop blood pressure or cholesterol medicine on your own.
[1][2]

Drug interactions

Drug interactions
Medicine / substanceEffectSeverity
Blood thinners and aspirinGarlic supplements may increase bleeding risk. There are no separate data for black garlic; use the same caution and ask your doctor. [1]Moderate

Side effects

  • Breath and body odour, abdominal pain, flatulence and nausea (reported for garlic)
  • Allergic reactions
  • No serious side effects were reported in studies

⚕ When to see a doctor

  • If high fever, shortness of breath or purulent/bloody phlegm develops
  • If symptoms do not improve within 1–2 weeks or worsen
  • If severe abdominal pain, jaundice, rash or allergic reaction occurs

Frequently asked questions

Does black garlic lower blood pressure?

In a randomized trial of 67 people, its extract lowered diastolic blood pressure by about 3.7 mmHg after 6 weeks, without changing systolic pressure. It is a single small study and does not replace blood pressure medicine.

Does black garlic lower cholesterol?

In studies, LDL and total cholesterol did not fall significantly in people with high cholesterol. It has not been shown to work for this purpose.

What is the difference between black garlic and regular garlic?

Black garlic is made by keeping fresh garlic in a warm, humid environment for weeks; it tastes sweeter and smells milder. Studies on regular garlic cannot be applied directly to black garlic.

Does black garlic thin the blood?

There are no separate data for black garlic, but garlic supplements are known to possibly increase bleeding risk. Ask your doctor if you take blood thinners.

Can I eat black garlic while pregnant?

Apart from small amounts in food, garlic above food amounts may not be safe in pregnancy and breastfeeding. Do not use supplements or extracts.

Sources

Source type is not an efficacy rating. A monograph may document traditional use or safety. Claim numbers link to the relevant source; the access date does not indicate professional approval.

  1. Garlic: Usefulness and SafetyNIH NCCIH · 2025 · Official agency informationSource accessed:
  2. Effects of an Optimized Aged Garlic Extract on Cardiovascular Disease Risk Factors in Moderate Hypercholesterolemic Subjects: A Randomized, Crossover, Double-Blind, Sustained and Controlled StudyNutrients · 2022 · Randomized controlled trialSource accessed:
  3. Effect of Black Garlic Consumption on Endothelial Function and Lipid Profile: A Before-and-After Study in Hypercholesterolemic and Non-Hypercholesterolemic SubjectsNutrients · 2023 · Observational study / case seriesSource accessed:

Cite This Page

Black Garlic (Allium sativum). Herbadex — Doğal Şifa Rehberi (2026). https://herbadex.com/en/herb/black-garlic/

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