Does garlic prevent infection?

Garlic may improve resistance to infections. Garlic appears to be effective against many kinds of microbes that cause infections. Allicin, one of the main biologically active compounds of garlic, is an antibiotic. At least against one bacterial species, allicin is more potent than penicillin.

In the test tube, extracts of allicin can disable infection-causing amoebas by inhibiting key processes that many microbes need to cause infections.

Test-tube studies show garlic extracts to be protective of tissue against certain viruses. One study found that the garlic compounds ajoene and allicin were the most effective ingredients of garlic extracts against herpes simplex, common cold and a number of other viruses.

Anthony L. Komaroff, MD
Internal Medicine
Garlic may have some infection-fighting capability. In laboratory dishes, researchers have seen garlic work against bacteria, viruses, and fungi. Although this is promising, there haven't been enough well-designed human studies conducted to know whether this translates into human benefits. One study that looked at southern European populations found an association between the frequency of consumption of garlic and onions and a lower risk of some common cancers. Until more is known, however, it's too early to recommend garlic as a way of treating or preventing infections or controlling cancer.

Continue Learning about Garlic



Garlic is used as an herbal treatment for conditions of the heart, such as high blood pressure, high cholesterol and hardening of the arteries. As with any herbal remedies, the effectiveness of this treatment is not widely documen...

ted, so best to consult with your doctor on using garlic supplements to treat blood pressure, cholesterol or any other conditions. Learn more about garlic from our experts.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.