Introduction

This fact sheet provides basic information about garlic--uses, potential side effects, and resources for more information. Garlic is the edible bulb from a plant in the lily family. It has been used as both a medicine and a spice for thousands of years.

Common Names--garlic

Latin Names--Allium sativum

What It Is Used For

• Garlic's most common uses as a dietary supplement are for high cholesterol, heart disease, and high blood pressure.
• Garlic is also used to prevent certain types of cancer, including stomach and colon cancers.

How It Is Used

Garlic cloves can be eaten raw or cooked. They may also be dried or powdered and used in tablets and capsules. Raw garlic cloves can be used to make oils and liquid extracts.

What the Science Says

• Some evidence indicates that taking garlic can slightly lower blood cholesterol levels; studies have shown positive effects for short-term (1 to 3 months) use. However, an NCCAM-funded study on the safety and effectiveness of three garlic preparations (fresh garlic, dried powdered garlic tablets, and aged garlic extract tablets) for lowering blood cholesterol levels found no effect.
• Preliminary research suggests that taking garlic may slow the development of atherosclerosis (hardening of the arteries), a condition that can lead to heart disease or stroke.
• Evidence is mixed on whether taking garlic can slightly lower blood pressure.
• Some studies suggest consuming garlic as a regular part of the diet may lower the risk of certain cancers. However, no clinical trials have examined this.
• NCCAM is supporting studies looking at how garlic interacts with certain drugs and how it can thin blood.