Also listed as: Allium sativum
Garlic has been used as both food and medicine in many cultures for thousands of years, dating as far back as the time that the Egyptian pyramids were built. Later, gravediggers in early 18 th -century France drank a concoction of crushed garlic in wine they believed would protect them from the plague that killed many people in Europe. More recently, during both World Wars I and II, soldiers were given garlic to prevent gangrene. Today garlic is used to help prevent heart disease, including atherosclerosis (plaque buildup in the arteries that can block the flow of blood and possibly lead to heart attack or stroke), high cholesterol, high blood pressure, and to improve the immune system. Garlic may also protect against cancer.
While the science is not definitive at this point, much of the research is showing promise, and many clinicians continue to report improvements in the areas of cancer protection and heart-related risk factors for patients.
Garlic has antioxidant properties. Antioxidants help destroy free radicals -- particles that can damage cell membranes, interact with genetic material, and possibly contribute to the aging process as well as the development of a number of conditions including heart disease and cancer. Free radicals occur naturally in the body, but environmental toxins (including ultraviolet light, radiation, cigarette smoking, and air pollution) can also increase the number of these damaging particles. Antioxidants can neutralize free radicals and may reduce or even help prevent some of the damage they cause over time.
There are several types of garlic preparations. Most clinical studies have been performed on aged garlic extract (AGE) or enteric coated, dried garlic tablets. The conditions for which garlic is showing the most promise include:
Studies report that garlic consumption may decrease the progression of cardiovascular disease. Cardiovascular disease is associated with several factors, including raised serum total cholesterol, raised low density lipoprotein (LDL), and an increase in LDL oxidation (free radical damage), increased platelet aggregation (clumping), hypertension, and smoking. Garlic may help decrease LDL and total cholesterol levels while raising good cholesterols (high density lipoprotein, or HDL), decrease platelet aggregation (helps the blood flow more easily), and decrease blood pressure. Recently, garlic was also found to decrease two other markers of cardiovascular disease, homocysteine and C-reactive protein.
Garlic may also decrease blood pressure. Numerous studies have reported small reductions in systolic and diastolic blood pressure associated with the use of oral garlic.
A well-designed study of nearly 150 people supports the value of garlic for preventing and treating the common cold. In this study, people received either garlic supplements or placebo for 12 weeks during "cold season" (between the months of November and February). Those who received the garlic had significantly fewer colds than those who received placebo. Plus, when faced with a cold, the symptoms lasted a much shorter time in those receiving garlic compared to those receiving placebo.
Garlic may strengthen the immune system and may help the body fight diseases such as cancer. Laboratory studies suggest that garlic may have some anti-cancer activity. Studies which follow groups of people over time suggest that people who have more raw or cooked garlic in their diet are less likely to have certain types of cancer, particularly colon and stomach cancers. Dietary garlic may also offer some protection against the development of breast, prostate, and laryngeal (throat) cancers.
While these results are promising, more research is needed to best understand whether dietary intake of garlic and other plants in the same family (such as onions, leeks, scallions, chives, and shallots) truly help to protect us from cancer.
Garlic originally came from central Asia, and is now cultivated throughout the world. Garlic is a perennial that can grow 2 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 - 20 cloves, and each clove weighs about 1 gram. Garlic supplements can either be made from fresh, dried, aged, or garlic oil, and each may have different effects on the body.
There are several important components of garlic that hav