Garlic

Garlic is an herb that has long been used in cooking and in medicine. When a garlic bulb is cut or crushed, an amino acid by-product called allicin is released. Allicin is responsible for garlic’s strong odor and medicinal properties.

Because the active ingredients are destroyed when the garlic is crushed, the amount of active ingredient in the various forms of garlic varies greatly. Aged garlic extract (AGE), made from garlic allowed to age for at least 20 months, has more stable active compounds than most forms. Consuming garlic supplements in this form appears to provide the greatest health benefits and with fewer adverse effects.

(See also Overview of Dietary Supplements Overview of Dietary Supplements Dietary supplements are used by about 75% of Americans. They are the most common therapies included among integrative medicine and health (IMH) and complementary and alternative medicine (CAM)... read more .)

Garlic reduces the normal clotting tendency of platelets (particles in the blood that help stop bleeding). Because garlic stops microorganisms (such as bacteria) from reproducing, it has some antiseptic and antibacterial effects. Proponents also claim that garlic can

The strongest evidence available for garlic supplementation, specifically AGE, is for lowering blood pressure. In large doses, garlic can reduce systolic and diastolic blood pressure slightly.

Most studies have used aged garlic extracts. Preparations formulated to have little or no odor may be inactive and need to be studied.

Garlic usually has no harmful effects other than making the breath, body, and breast milk smell like garlic. However, consuming large amounts can cause nausea and burning in the mouth, esophagus, and stomach.

Small amounts of garlic that may be eaten as part of the diet are unlikely to cause drug interactions. However, larger amounts as may be taken as supplements may interact with drugs that prevent blood clots (such as warfarin), increasing risk of bleeding. Thus, garlic should not be eaten or taken as a supplement 2 weeks before surgery or before a dental procedure.

Garlic may interact with drugs used to treat human immunodeficiency virus (HIV) infections (such as saquinavir) making them less effective, and may interact with drugs that decrease blood sugar levels Medication Treatment of Diabetes Mellitus Many people with diabetes require medication to lower blood glucose levels, relieve symptoms, and prevent complications of diabetes. There are two types of diabetes mellitus Type 1, in which... read more causing excessive decreases in blood sugar levels.

Garlic can also add to the effects of blood pressure–lowering drugs and thus lower blood pressure too much. Garlic can also interact with tacrolimus (a drug to prevent rejection of a transplanted organ), resulting in increased levels of tacrolimus and liver damage. Animal studies have shown that garlic decreases isoniazid levels.

Garlic appears to lower blood pressure, total cholesterol and LDL cholesterol levels, and fasting blood sugar levels. As a result, garlic may help decrease risks of cardiovascular problems. Garlic is relatively safe, but people should talk with their doctor before taking garlic if they