Supplements Dietary Supplements What Is Allicin? Garlic's Heart-Health Booster By Cathy Wong Cathy Wong Facebook Twitter Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health. Learn about our editorial process Updated on March 13, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Arno Kroner, DAOM, LAc Medically reviewed by Arno Kroner, DAOM, LAc Facebook LinkedIn Twitter Arno Kroner, DAOM, LAc, is a board-certified acupuncturist, herbalist, and integrative medicine doctor practicing in Santa Monica, California. Learn about our Medical Expert Board Print Verywell / Anastasia Tretiak Table of Contents View All Table of Contents Health Benefits Possible Side Effects Dosage and Preparation What to Look For Frequently Asked Questions Allicin is a compound that may help ease inflammation and block free radicals that harm cells and tissues in your body. The compound is one of the main active components of garlic and what gives it its distinct taste and scent. Alliin is a chemical found in fresh garlic. An enzyme called alliinase is activated when the clove is chopped or crushed. This enzyme converts alliin into 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 levels. This article will discuss the possible health benefits of allicin, risks and side effects, and how to use it. Commonly Known As AllicinAllium sativumGarlic Health Benefits Allicin may help guard against health issues like heart disease and cancer. It may also protect against blood vessel damage by helping to lower your: Blood sugar Blood pressure Cholesterol 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 viruses and fungi. Many studies have shown that the allicin in garlic may support health in various ways. Support Blood Vessel Health 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) found that regular use of compounds in garlic lowered people's cholesterol levels by about 8%. 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: Low-density lipoprotein (LDL) Total cholesterol A more recent review of studies also supports these findings. The results of eight of nine reviews found a marked decrease in total cholesterol. Lower 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 (SBP, the top number in a BP reading) was around six points lower compared to people who took a placebo (sugar pill). Their diastolic blood pressure (DBP, the bottom number) was almost nine points lower. A double-blind randomized controlled trial published in 2021 backed up these results. Adults with nonalcoholic fatty liver disease (NAFLD) in the study received either a placebo or two tablets with 400 milligrams (mg) of garlic daily for 15 weeks. Those who took the supplements had a nearly eight-point decrease in SBP and more than a five-point decrease in DBP at the end of the trial. 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. Protect Against Cancer n 1990, the National Cancer Institute praised garlic for its ability to guard against cancer. 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: Breast Colon Liver Head and neck Ovaries Pancreas Prostate Skin Possible Side Effects Few side effects and health risks have been tied to allicin use. But be sure to talk with your doctor about how it may fit into your care plan before adding it to your regimen. Discuss how the compound can impact your health or interact with any drugs and health aids you take such as: Drugs, both prescribed and over-the-counter (OTC)Dietary supplementsHerbal remediesEssential oils Allicin supplements have a few risks you should be aware of. Digestive Issues The compound may cause issues such as: BelchingGasNauseaDiarrheaHeartburn 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. Be sure to talk with your doctor if you also take a blood thinner such as warfarin and other herbal and OTC aids that can thin your blood such as: AspirinGingko bilobaVitamin E If you are due to have surgery or another procedure, your doctor may recommend that you avoid garlic and products with its compounds for some time beforehand. Drug Interactions and Precautions If you have blood pressure or blood sugar issues and take medicines to manage these, be sure to talk with your doctor before you try allicin. 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 to take the compound for: Pregnant womenNursing mothersChildren Recap Allicin poses few known side effects and health risks. These may include digestive issues and risk of bleeding.Children, people who are pregnant or nursing, or people who have health conditions should check with their health provider before using Allicin. Verywell / Anastasia Tretiak Dosage and Preparation Allicin 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 the specific product. In general, it's best to follow the instructions on the label. A single garlic clove has about 5 mg to 18 mg of allicin. The doses most often used in studies range between 300 mg and 1,500 mg. 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. Be sure to talk with your doctor about the dose that’s right for you. What to Look For Stomach acids can dissolve tablets and garlic enzymes before they have the chance to work. 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 was as bioavailable as those from equivalent amounts of crushed raw garlic when taken with a meal. Supplements aren't regulated by the Food and Drug Administration, so their quality and potency can vary. Be sure the product has been certified by one or more of these agencies: Consumer LabsU.S. Pharmacopeia ConventionNSF International 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 for pregnant or breastfeeding women. If you're interested in trying allicin supplements, talk with your doctor or pharmacist first about whether they're safe and likely to be beneficial for you. Frequently Asked Questions Does cooking reduce the allicin in garlic? Yes, cooked garlic has less allicin than raw garlic. 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. Learn More: Does Garlic Reduce Your Risk of Cancer? 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 the effective dose should be. Learn More: Home Remedies for Chest Congestion Can garlic treat a yeast infection? Placing garlic cloves inside the vagina does not cure a yeast infection. It's best not to put any object into your vagina other than a tampon or suppository prescribed by your healthcare provider. Learn More: What You Should Know About Yeast Infections Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 14 Sources 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. White D. Healthy uses for garlic. Nurs Clin North Am. 2021;56(1):153-156. doi:10.1016/j.cnur.2020.12.001 Shang A, Cao SY, Xu XY, et al. Bioactive compounds and biological functions of garlic (allium sativum L.). Foods. 2019;8(7):246. doi:10.3390/foods8070246 Doma K, Devantier-Thomas B, Gahreman D, Connor J. Selected root plant supplementation reduces indices of exercise-induced muscle damage: s systematic review and meta-analysis. Int J Vitam Nutr Res. 2020;1-21. doi:10.1024/0300-9831/a000689 Ried K, Toben C, Fakler P. Effect of garlic on serum lipids: an updated meta-analysis. Nutr Rev. 2013;71(5):282-99. doi: 10.1111/nure.12012. 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