There’s conflicting evidence about whether garlic lowers blood cholesterol levels. If it does, the effect is small, and low-density lipoprotein (LDL) cholesterol (the so-called “bad” cholesterol that’s linked to increased heart disease risk) may not be reduced at all.

Garlic may be helpful for high blood pressure, but the evidence is weak.

Some studies indicate that certain groups of people who eat more garlic may be less likely to develop certain cancers, such as stomach and colon cancers. However, dietary supplement form has not been shown to help reduce the risk of these cancers. The National Cancer Institute recognizes garlic as one of several vegetables with potential anticancer properties but does not recommend using dietary supplements for cancer prevention.

There’s not enough evidence to show whether it is helpful for the common cold.

Side Effects Of Garlic

Garlic is probably safe for most people in the amounts usually eaten in foods.

Side effects include breath and body odor, heartburn, and an upset stomach. These side effects can be more noticeable with raw garlic. Some people have allergic reactions.

Taking garlic may increase the risk of bleeding. If you take an anticoagulant (blood thinner) such as warfarin (Coumadin) or if you need surgery, tell your health care provider if you’re taking or planning to take dietary supplements.

Garlic has been found to interfere with the effectiveness of some drugs, including saquinavir, a drug used to treat HIV infection.


Tell all your health care providers about any complementary or integrative health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.


All of this information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.