Table of ContentsView AllTable of ContentsUsesSide EffectsPrecautionsDosageToxicityInteractionsHow to StoreSimilar SupplementsSources & What to Look ForFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
Uses
Side Effects
Precautions
Dosage
Toxicity
Interactions
How to Store
Similar Supplements
Sources & What to Look For
Frequently Asked Questions
Allicin is a compound that may help ease inflammation and block free radicals, unstable molecules that harm cells and tissues in your body.Research suggests the compound may also help lower cholesterol, prevent bacterial infections, and support cancer prevention.
Allicin is derived from garlic. Specifically, it’s formed when garlic is crushed or chopped, which activates the enzyme alliinase that converts the compound alliin into allicin.Allicin is primarily responsible for garlic’s distinct aroma, along with many of the health benefits attributed to it.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
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Uses of Allicin
Many studies have shown that the allicin in garlic may support health in various ways. Here’s a look at some of the more compelling evidence.
Cholesterol
In general, adults in the study with slightly elevated cholesterol levels—above 200 milligrams per deciliter (mg/dL)—who took garlic for at least two months had lower:
A 2016 review of studies also supports these findings. The results of eight of nine reviews found a marked decrease in total cholesterol.Lowering total and LDL cholesterol levels (when they’re elevated) helps reduce your risk of heart attack and stroke.
Blood Pressure
Research suggests that allicin may help lower blood pressure and keep it within a healthy range.
In adults with high blood pressure who took garlic supplements, the mean systolic blood pressure (the top number in a blood pressure reading) was around 8 points lower than those who took a placebo (sugar pill). Their diastolic blood pressure (the bottom number) was about 5 points lower.
Cancer
In 1990, the National Cancer Institute (NCI) praised garlic for its ability to guard against cancer.Since then, multiple preclinical 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 the following cancers:
Allicin is a sulfur-containing compound. The role of sulfur compounds is being studied in the prevention of colon cancer, as well as in slowing the progression of colon cancer. Sulfur compounds are thought to positively affect the gut microbiota and intestinal lining, as well as disrupt cancer cell growth.
It’s important to note that most of these studies were done on animal models or cells in a test tube. Robust human trials are needed to learn more about allicin’s effects on cancer.
The NCI does not recommend taking garlic supplements to prevent cancer.
Infection
Garlic is a natural antibiotic whose use has been documented since the 1300s. Allicin is the compound responsible for garlic’s ability to fight illness. It’s considered broad-spectrum, meaning it’s able to target the two main types of bacteria that cause disease.
Allicin also seems to enhance the effect of other antibiotics. Because of this, it may help combat antibiotic resistance, which happens when, over time, bacteria do not respond to medicines meant to kill them.
Other Uses
In addition to the potential health benefits listed above, some people use allicin to help muscle recovery after a workout.
What Are the Side Effects of Allicin?
Your healthcare provider may recommend you take allicin to help lower blood pressure, blood sugar, or cholesterol or for other conditions. Allicin has some side effects to be aware of, and these may be common or severe.
Common Side Effects
Allicin causes a garlic odor or breath in about one in three people who use it.
High doses may also cause digestive issues, such as:
These side effects may be more common with raw garlic than with supplements.Taking allicin with food may help limit or prevent these problems.
Severe Side Effects
Skin blisters and burns have been reported with raw garlic topical application (on the skin).High doses may cause liver damage.
It is not known whether it is safe to take garlic supplements for:
Garlic may cause allergies and shouldn’t be taken if you are allergic to plants in the lily family, including:
If you are due to have surgery or another procedure, your healthcare provider may recommend that you avoid garlic and products with its compounds for seven to 10 days beforehand.This is because garlic can increase the risk of bleeding.
Verywell / Anastasia Tretiak
Dosage: How Much Allicin Should I Take?
Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.
There is no standard dose for allicin. The dose can vary based on your health needs and the specific product. In general, it’s best to follow the instructions on the label.
Standard doses used in blood pressure studies were 600 to 900 milligrams (mg) daily of garlic powder for up to 24 weeks; 600 mg of garlic powder contains approximately 7.8 mg of allicin.
Higher daily doses are often divided into multiple doses taken throughout the day. Breaking up doses may also help limit some of the digestive side effects.
Talk with your healthcare provider about the correct dose for you.
What Happens if I Take Too Much Allicin?
So far, studies show little evidence of toxicity from allicin. One report suggested thatsepticemia(a serious blood infection),bradycardia(slow heart rate), or loss of consciousness could occur if high doses of allicin are taken for long periods.
More research is needed to determine if allicin could be toxic to adults at high doses.
If you are concerned about these or any other potential side effects, always discuss the use of allicin with your healthcare provider.
Allicin and other garlic compounds help keepblood clotsfrom forming.This may raise the risk of bleeding.Talk with your healthcare provider if you also take ablood thinnersuch asJantoven (warfarin), or other herbal and OTC aids that can thin your blood, such as:
Avoid high doses (more than 4 grams of fresh garlic or 3 mg of allicin) if you take warfarin or other blood thinners.
Allicin also interacts with a class of medicines called protease inhibitors used in human immunodeficiency virus (HIV) treatment.
If you have blood pressure or blood sugar issues and take medicines to manage these, be sure to talk with your healthcare provider before you try allicin. Using allicin at the same time may cause your blood pressure or blood sugar to drop too low, though there is not much evidence that these interactions cause harm.
It is essential to carefully read a supplement’s ingredient list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications.
How to Store Allicin
Always store allicin products as directed on the package—typically in a cool, dry place and away from children and pets.
Several supplements have similar activities as allicin. For example, some people take omega-3 fatty acids to lower cholesterol.
Other supplements that may help control blood pressure include:
Supplements that may lower blood sugar include:
Many other supplements have been studied to prevent cancer. Some examples are:
Popular supplements that may be taken to prevent or treatcoldsinclude:
Sources of Allicin and What to Look For
You can get allicin from food and/or supplements. Generally getting allicin through its food source (chopped garlic) may be considered to be most effective.
Food Sources of Allicin
Allicin is found in raw garlic, one of the most commonly used foods in cooking.It is also volatile (unstable and quickly changes into other chemicals).
A garlic clove has about 5 to 18 mg of allicin. Pure allicin only remains stable in freshly crushed or cut garlic for a short time. But letting garlic sit for 10 minutes after crushing or cutting it may help boost allicin levels.Try not to heat it above 140 degrees F; temperatures above this may degrade the amount of allicin.
Allicin Supplements
Allicin is found in garlic powder supplements, which can be formulated as:
The FDA does not regulate supplements, so their quality and potency can vary. Amounts of allicin released in the body are often lower than the product labels claim.
Supplement FactsActive ingredients:DiallylthiosulfinateAlternative name:Allium sativum,garlic, nectar of the gods, poor man’s camphor, stinking roseLegal status:Over-the-counter (OTC) supplementSuggested dose:2–4 grams (g) of crushed raw garlic; 7.2 g of aged garlic extract or one dried garlic powder tablet two to three times a daySafety considerations:Insufficient data in children and pregnancy, but it may impact a nursing child’s digestion
Supplement Facts
Active ingredients:DiallylthiosulfinateAlternative name:Allium sativum,garlic, nectar of the gods, poor man’s camphor, stinking roseLegal status:Over-the-counter (OTC) supplementSuggested dose:2–4 grams (g) of crushed raw garlic; 7.2 g of aged garlic extract or one dried garlic powder tablet two to three times a daySafety considerations:Insufficient data in children and pregnancy, but it may impact a nursing child’s digestion
Summary
Allicin is one of the main active compounds derived from garlic. It may help prevent certain cancers and may help lower blood sugar, cholesterol, and blood pressure. It may help your muscles recover after a workout and protect against infections.
Allicin supplements have few risks. It might cause some stomach upset and increase the risk of bleeding. Its safety isn’t known for children or pregnant or breastfeeding women.
If you’re interested in allicin supplements, talk with your healthcare provider or pharmacist about whether they’re safe and beneficial for you.
Some studies suggest garlic may help prevent or treat colds.However, current research hasn’t determined what the effective dose should be or even if it helps at all.Learn MoreHome Remedies for Chest Congestion
Some studies suggest garlic may help prevent or treat colds.However, current research hasn’t determined what the effective dose should be or even if it helps at all.
Learn MoreHome Remedies for Chest Congestion
Learn MoreWhat You Should Know About Yeast Infections
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