What Is Allicin?

Garlic's Heart-Health Booster

Allicin capsules and tablets

Verywell / Anastasia Tretiak

Allicin is a compound that may help ease swelling and impede free radicals that harm cells and tissues within your body and lead to disease.

Allin is an amino acid found in fresh garlic. An enzyme called alliinase is released when the clove is injured or damaged.

This enzyme converts the amino acid into allicin.

The compound is one of the main active components of garlic and what gives it its distinct taste and scent.

Pure allicin only remains stable in freshly crushed or cut garlic for a short time. But letting it sit for around 10 minutes after crushing or cutting it may help boost levels.

The compound is also added to dietary products to help preserve its effects.

This article will discuss:

  • How allicin helps support good health
  • What risks and side effects are known
  • What’s the proper dosage
  • How it’s prepared
  • What to look for when choosing a product with it

Commonly Known As

  • Allicin
  • Allium sativum
  • Garlic

Why Is Allicin Used?

Allicin may help guard against health issues like heart disease and cancer.

It may also protect against health issues that impact your blood vessels and help lower your:

Some studies have also found that allicin may help your muscles recover faster after you work out.

And the compound is thought to support immune health by warding off agents that cause illness such as virus and fungus.

Does Allicin Support Health?

Many studies have shown that the allicin in garlic may support health in various ways.

Allicin May Support Healthy Blood Vessels

Studies have shown that the allicin in garlic supports blood vessel health.

It may help improve blood pressure (BP) control and keep the blood vessel disease known as atherosclerosis at bay.

A review of 39 randomized controlled trials (RCTs) compounds in garlic lowered the risk of cardiac events in adults at age 50 by close to 40 percent.

It also helped lower the “bad fats” within your blood when taken for at least two months. Tests showed that adults in the study had lower:

A more recent review of studies also supports these findings. The results of eight of nine reviews found a marked decrease in total cholesterol.

Allicin Helps Control High Blood Pressure

Research suggests that allicin may help lower blood pressure and keep it within a healthy range. 

In adults with high blood pressure, the mean systolic blood pressure (SBP or top reading) was around 6 points lower while diastolic blood pressure (DBP or bottom number) was almost 9 points lower.

A double-blind RCT published in 2021 backed up these results. Adults in the study received either placebo or two tablets of 400 mg garlic daily for 15 weeks.

The authors noted a nearly 8-point decrease in SBP and more than 5-point decrease in DBP at the end of the trial.

The people in this study were all living with nonalcoholic fatty liver disease (NAFLD).

Along with high blood pressure, NAFLD is closely tied to other health issues such as heart disease and metabolic syndrome.

NAFLD impacts your liver over the long haul but you may be able to keep the disease and the health problems tied to it at bay with lifestyle habits such as healthful eating.

Recap

Allicin may help you gain better control over your high blood pressure. Research has noted a decrease in SBP and DBP ranging from 2 to almost 9 mm Hg.

Allicin May Help Protect Against Some Cancers

The National Cancer Institute praised garlic for its ability to impede and guard against cancer in 1990.

Since then, multiple studies have shown that allicin and other active garlic compounds may shield against some cancers and keep cancer cells from spreading.

Research has explored its role against cancers of the:

What Are the Risks and Side Effects of Allicin?

Few side effects and health risks have been tied to allicin use. But be sure to talk with your healthcare provider about how it fits into your care plan before adding it to your regimen.

Discuss how the compound can impact your health or interact with drugs and health aids you take such as:

  • Drugs prescribed and over the counter (OTC)
  • Dietary supplements
  • Herbal aids
  • Essential oils

Using allicin carries the risk of:

Digestive Issues

The compound may cause issues such as:

  • Belching
  • Gas
  • Nausea
  • Diarrhea
  • Heartburn

Taking it with food may help limit or prevent these problems. 

Bleeding

Allicin may raise the risk of bleeding. That is because this and other garlic compounds help keep blood clots from forming. 

Part of your care plan will likely involve not having certain foods and drugs within a set time before surgery. This includes foods such as garlic and products with its compounds.

Be sure to talk with your health provider if you also take a blood thinner such as warfarin and other herbal and OTC aids that can thin your blood such as:

  • Aspirin
  • Gingko biloba
  • Vitamin E

Drug Interactions and Other Unknown Risks

If you have blood pressure or blood sugar issues and take medicines to manage these, be sure to talk with your health provider before adding allicin to your care plan.

Using allicin at the same time may cause your blood pressure or blood sugar to drop too low.

It is not known whether it is safe for all people to take the compound. This includes people with special health needs such as:

  • Pregnant women
  • Nursing mothers
  • Children

Recap

Allicin poses few known side effects and health risks. These may include digestive issues and risk of bleeding.

 

People with certain health issues and special health needs should check with their health provider before adding the compound to their health routine.

Allicin tablets

Verywell / Anastasia Tretiak

How is Allicin Prepared and What Dose Works Best?

Products are sold in pill or tablet form and may have garlic or allicin on the label. They may also come in powder, oil, or extract form.

There is no standard dose for the compound. The dose can vary based on your health needs and product form.

A single garlic clove has about 5 mg to 18 mg of allicin. The doses most often studied range between 300 mg and 1,500 mg.

Higher daily doses are often divided into multiple doses. Breaking up doses may also help limit side effects.

Be sure to talk with your doctor about the dose that’s right for you.

What to Look for When Choosing an Allicin Product?

Stomach acids can dissolve tablets and garlic enzymes before they have the chance to work. Coated tablets may help prevent this. 

But a 2018 review of garlic and allicin supplements found that tablets with enteric coating were not more bioavailable (able to be used and absorbed by the body) than those without it.

The study also found that allicin derived from garlic powder supplements were as bioavailable as those from equivalent amounts of crushed raw garlic when taken with a meal.

Be sure the product has been certified by one or more of these agencies no matter which product you choose to use:

  • Consumer Labs
  • U.S. Pharmacopeial Convention
  • NSF International

Summary

 Allicin is one of the main active compounds derived from garlic. It helps guard against certain cancers and may help lower blood:

  • Lipids
  • Pressure
  • Sugar

It may help your muscles recover after your workout and it can ward off illness caused by agents such as virus and fungus.

Taking the compound carries a few side effects and health risks. Most involve digestive issues or risk of bleeding.

Aim to have a frank talk with your health provider about these risks and side effects before adding the compound to your health routine. Also discuss how it can bolster or harm your health.

This is especially true since there is no standard dose for allicin. Your health provider can help you decide on the right dose based on:

  • Why you would like to use it
  • What your health needs and risks are
  • What form you prefer to use

Be sure the allicin product you choose has been certified by one of the main agencies that oversee its quality.

Frequently Asked Questions

  • Does cooking reduce the allicin in garlic?

    Yes. But because allicin forms after garlic is chopped, you can boost the active amount by waiting at least 10 minutes before you cook it. It's also best not to expose garlic to heat higher than 140 degrees. One way to do this is to add garlic during the final stages of cooking.

  • How much garlic should I take to treat a cold?

    Some studies suggest garlic may help prevent or treat colds. But current research hasn't determined what this dose or dose range should be.

  • Can internal garlic use treat a yeast infection?

    There's no clinical proof that placing garlic inside the vagina cures a yeast infection. Oral garlic tablets have been shown to have some effect in various lab strains of the fungus. But the practice of placing cloves inside the vagina hasn't been vetted by strong science. It's best not to put any foreign object into your vagina other than a tampon or suppository prescribed by your healthcare provider.

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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