Garlic

The pungent odor of garlic, which is offensive to some people, is noticeable on your breath and even your skin after you eat it. Despite this, herbalists worldwide consider garlic one of the most important herbal medicines. It has been used as both food and medicine in many cultures for thousands of years. The construction workers who built the Egyptian pyramids ate large amounts of garlic to protect themselves from diseases. Gravediggers in early eighteenth-century France drank a concoction of crushed garlic in wine to keep them from getting a plague that killed many people in Europe. During both World War I and II, soldiers were given garlic to prevent gangrene.

Plant Description

Garlic originally came from central Asia, and is now found throughout the world. Garlic is a perennial that can grow two feet high or more. The most important part of this plant for medicinal purposes is the compound bulb. Each bulb is made up of 4 to 20 cloves, and each clove weighs about 1 gram.

What's It Made Of?

The main active ingredient in garlic is alliin. Alliin is an odorless chemical relative of the sulfur-containing amino acid cysteine. When garlic bulbs are crushed, alliin is converted into another compound called allicin. Allicin is the active compound that gives garlic its characteristic odor and many of its healing benefits.

Fresh garlic contains about 0.25 to 1.15 percent of allicin. The total amount of sulfur-containing substances in garlic is about 25 to 35 percent after the bulbs have been crushed. Allicin gives garlic its antibiotic effects. Allicin also helps lower cholesterol by blocking cells from making more cholesterol. Ajoene is another important active compound in garlic that helps prevent hardening of the arteries and stroke.

Available Forms

Garlic products are made from whole fresh garlic, fresh or dried garlic cloves, or oil of garlic. But the amount of allicin in commercial products can vary, depending on how the product was prepared, or on the percentage of active compounds in fresh garlic cloves. Not all garlic starts with the same amount of active ingredients.

Aged garlic products are made by fermenting garlic. These products are odor-free, but they don't have many health benefits. Fermentation inactivates most of the active ingredients, so it's important that you carefully read the label on all garlic products. It is best to use standardized garlic products to be sure you're getting a specified concentration of allicin and other active substances.

How to Take It

For years, people have taken garlic to help prevent atherosclerosis (hardening of the arteries) and high blood pressure, colds, coughs, bronchitis, gastrointestinal problems, and menstrual pain. Medical research shows that garlic can kill many types of bacteria, some viruses and fungal infections, and even intestinal parasites. Garlic is also an antioxidant and it can boost your immune system. Garlic may even help prevent cancer. But garlic is best known for its favorable effects on cardiovascular health. Garlic is effective in treating and preventing high cholesterol and triglyceride levels, atherosclerosis, and respiratory infections such as colds and cough.

You can take garlic in the following forms to help prevent cardiovascular problems and the common cold.

• Capsules: 1,000 to 3,000 mg daily (lower doses for prevention, higher for treatment)
• Oil: 0.03 to 0.12 ml, three times a day

Precautions

Avoid eating too much garlic because it might give you a stomachache. Also, if you handle too much fresh or dried garlic, you might get burn-like skin lesions or other skin irritations. If you know that your blood clots slowly, don't take large therapeutic doses of garlic. This is especially important if you're going to have surgery. Too much garlic can increase your risk for bleeding during or after the operation. If you're pregnant or nursing, talk to your health care provider before taking or eating large amounts of garlic. In small amounts, it's fine, but extremely large doses can stimulate the uterus and may even cause a miscarriage.

Possible Interactions

Garlic has blood-thinning properties. Therefore, if you are taking anticoagulant (blood-thinning) medications such as aspirin, you should refrain from consuming large amounts of garlic, either fresh or commercially processed.

Supporting Research

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