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Garlic extract

Best studied for: High blood pressure; High cholesterol; Frequent colds and immune support. Best known for supporting heart health.

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What is garlic extract? Garlic extract is a concentrated form of garlic that is made by soaking crushed garlic cloves in a solvent, usually ethanol or water. This process extracts the active compounds found in garlic and creates a potent supplement that can be taken in capsule or liquid form. How does it work? Garlic extract is believed to work by producing a chemical called allicin, which is responsible for most of its health benefits. Allicin has been shown to have antimicrobial, antioxidant, and anti-inflammatory properties. Additionally, garlic extract contains other sulfur compounds that may also contribute to its medicinal effects. What are the active ingredients that are important for its medicinal properties? The active ingredient in garlic extract is allicin, which is formed when the enzyme alliinase converts alliin to allicin. Other sulfur compounds, such as diallyl sulfide and diallyl disulfide, may also contribute to its health benefits. What forms does it come in? Garlic extract is available in a variety of forms, including capsules, tablets, liquid extracts, and oils. When was it first used for medicinal purposes? Garlic has been used for medicinal purposes for thousands of years, dating back to ancient Egypt, Persia and Greece.

Helps

What does Garlic extract help with? Garlic extract is made from the garlic bulb. Healers and cooks have used it for more than 5,000 years . It shows up in Ayurvedic, Chinese, Egyptian, Mediterranean and Middle Eastern medicine. The human evidence is strongest for blood pressure and cholesterol. Other uses rest on smaller studies, on blood markers, or on lab work alone. Our files do not record trial sizes or doses, so none are named below. High blood pressure Strong evidence — several human clinical trials that agree; sizes and doses not on file. In a number of clinical trials, people taking garlic extract had lower blood pressure. Both the top and bottom numbers fell. The drop was largest in people who started with high readings. Evidence grade A · Traditional tier T3 High cholesterol and blood fats Good evidence — human trials on file, with sizes and doses not recorded. In human trials, total and LDL ("bad") cholesterol fell in people taking garlic. Blood fats called triglycerides fell too. HDL, the "good" kind, usually stayed flat or rose a little. Evidence grade B · Traditional tier T3 Catching colds often Good evidence — human clinical studies; sizes and doses not on file. In clinical studies, people taking garlic supplements caught fewer colds. Those who did get sick got better faster. In lab work, garlic compounds acted against viruses and bacteria. Evidence grade B · Traditional tier T3 Stiff arteries and heart risk Early evidence — small human studies of artery markers, not of heart attacks. Some human studies found less stiffness in artery walls with garlic extract. Early work also suggests it may slow calcium buildup in arteries. These are markers of risk, not counts of heart attacks or strokes. Evidence grade C · Traditional tier T3 Blood sugar in type 2 diabetes Early evidence — small or mixed human studies; doses not on file. Some human studies found lower fasting blood sugar in people taking garlic. Insulin sensitivity also improved in parts of this work. It is not a stand-in for diabetes medicine. Evidence grade C · Traditional tier T3 Blood that clots too easily Early evidence — human studies measuring platelet clumping, not clot events. In human studies, garlic made platelets slightly less likely to clump. Platelets are the blood cells that start a clot. This mild effect also means care is needed if you take blood thinners. Evidence grade C · Traditional tier T3 Long-term inflammation Early evidence — human studies of blood markers only. Studies of aged garlic extract found lower inflammation markers in blood. A compound called SAC mopped up free radicals in lab tests. Better markers do not always mean you feel better. Evidence grade C · Traditional tier T3 Gut balance and feeding good bacteria Long traditional use · not yet tested in trials — content analysis and lab work; no human trial on file. Garlic holds prebiotic fibres known as FOS (fructooligosaccharides). In lab studies, helpful gut bacteria feed on fibres of this kind. We hold no human trial on garlic and gut balance. Evidence grade insufficient · Traditional tier T3 Infections that keep coming back Long traditional use · not yet tested in trials — lab dish studies of allicin; no human trial on file. In lab dishes, allicin and related compounds acted against many bacteria, fungi and some parasites. Some people take garlic alongside standard care for Candida or H. pylori. Our files hold no human trial showing it clears these infections. Evidence grade insufficient · Traditional tier T3 What Garlic extract has not been shown to do Garlic has not been shown to raise HDL ("good") cholesterol much; in trials it mostly stayed the same. It has not been shown to replace blood pressure medicine. It has not been shown to replace diabetes medicine or insulin. It has not been shown to cut the number of heart attacks or strokes; the files hold risk markers only. How to read this: Each grade covers one use, not the whole herb. A mean

Garlic extract

Quick Facts

  • What it is: A concentrated form of garlic (Allium sativum) standardized for its active sulfur compounds, especially allicin and S-allylcysteine.
  • Main uses: Best known for supporting heart health, lowering blood pressure, and fighting infections naturally.
  • Best for: High blood pressure, High cholesterol, Frequent colds and immune support
  • Active ingredients: Allicin, S-allylcysteine (SAC), S-allylmercaptocysteine (SAMC), Diallyl disulfide (DADS), Diallyl trisulfide (DATS), Quercetin, Fructooligosaccharides (FOS)
  • Forms: Aged garlic extract (liquid or capsule), Allicin-standardized capsule, Garlic oil softgel, Enteric-coated tablet, Raw garlic powder capsule, Fresh clove (whole food)
  • Time to effect: Blood pressure and cholesterol improvements typically show up within 4–12 weeks of consistent use.
  • Side effects: Generally very safe; the most common complaints are garlic breath, digestive upset, and mild heartburn — especially with raw or high-dose forms.
  • Pregnancy & breastfeeding: Not assessed for this entry. Ask your doctor or midwife before use.

Educational information, not medical advice — ask your doctor or midwife.

What is garlic extract?

Garlic extract is a concentrated form of garlic that is made by soaking crushed garlic cloves in a solvent, usually ethanol or water. This process extracts the active compounds found in garlic and creates a potent supplement that can be taken in capsule or liquid form.

How does it work?

Garlic extract is believed to work by producing a chemical called allicin, which is responsible for most of its health benefits. Allicin has been shown to have antimicrobial, antioxidant, and anti-inflammatory properties. Additionally, garlic extract contains other sulfur compounds that may also contribute to its medicinal effects.

What are the active ingredients that are important for its medicinal properties?

The active ingredient in garlic extract is allicin, which is formed when the enzyme alliinase converts alliin to allicin. Other sulfur compounds, such as diallyl sulfide and diallyl disulfide, may also contribute to its health benefits.

What forms does it come in?

Garlic extract is available in a variety of forms, including capsules, tablets, liquid extracts, and oils.

When was it first used for medicinal purposes?

Garlic has been used for medicinal purposes for thousands of years, dating back to ancient Egypt, Persia and Greece.

Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.

Reviewed by the HealisticMD editorial team How we grade evidence →

Remedies related to Garlic extract

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