Cholesterol and Garlic


Garlic is a vegetable that offers many healing properties and has medicinal value. It may be best known for its ability to reduce your risk of developing heart disease. Various compounds found in abundance in this vegetable hinder plaque buildup in the arteries, enhance blood flow and may reduce damage caused by elevated LDL (bad) cholesterol levels. While most research studies have shown that garlic does not independently reduce blood cholesterol levels, it benefits heart health in other ways.

Identification and Description

Garlic (Allium sativum), a small vegetable, is a member of the Lily family. It is closely related to onions, chives and leeks. Garlic is best known for its aromatic odor and pungent flavor. This vegetable is arranged in a head, also known as the “bulb.” The bulb is made up of separate cloves. The entire vegetable (as well as each clove) is encased in paper-like wrappings, like those of an onion. The cloves are firm but can easily be cut or crushed. Garlic bulbs average about 2- inches in height by 2-inches in width.

A Cholesterol-Lowering Agent?

A meta-analysis of thirteen trials including over 1,000 subjects was published in the “Journal of Clinical Pharmacy and Therapeutics” in April 2009. Overall, garlic intake did not produce any statistically significant reduction in total blood cholesterol levels or LDL (“bad”) cholesterol levels when compared to placebo. The conclusion was that there are no significant beneficial effects of garlic on blood cholesterol levels. Another study, published in “Archives of Internal Medicine” in 2007 also concluded that garlic consumption (one clove daily, six days per week for six months) did not help lower LDL cholesterol in adults with moderately high cholesterol levels.

Heart Health Benefits

If garlic does not lower cholesterol levels directly, how does it benefit heart health? Güautnter Siegel, M.D., from the University of Medicine in Berlin, Germany presented research at the 6th Annual Conference on Arteriosclerosis, Thrombosis and Vascular Biology in Washington, D.C., suggesting that garlic helps prevent plaque formation in the arteries by acting in a manner similar to HDL (“good”) cholesterol. HDL cholesterol prevents the build-up of plaque in the arteries by blocking LDL cholesterol from binding to its receptor sites in blood vessels. Thus, while garlic doesn’t directly lower LDL cholesterol levels, it helps prevent it from doing damage.

Antioxidant Action

Garlic is rich in many essential vitamins and minerals that play a role in heart health, including vitamin C, an antioxidant nutrient. Vitamin C is particularly active in the bloodstream, a major water-soluble area of the body. Vitamin C helps prevent LDL cholesterol from oxidation. When LDL cholesterol is oxidized it forms plaque on artery walls, causing damage and increasing the risk of developing heart disease. Furthermore, vitamin C helps prevent further damage from free radicals (to the cardiovascular system) from such sources as pollution, chemicals and other toxins.

Recommended Preparation

Chopping or crushing garlic cloves stimulates the process that converts allin into allicin, a compound in garlic responsible for many of its health benefits. After chopping or crushing, wait a few minutes for maximum production of allicin. Lightly cooking crushed garlic cloves offers the most health benefits according to the Agricultural Research Service. Cooking garlic cloves for more than 10 minutes suppresses the action of garlic’s beneficial nutrients, so experts recommend lightly boiling, stir-frying, baking or microwaving it for less than 10 minutes.

About this Author

Michele Turcotte is a registered, licensed dietitian, and a certified personal trainer with the National Academy of Sports Medicine. She has more than 12 years of experience in clinical and corporate settings, and has extensive experience in one-on-one diet counseling and meal planning. She has written freelance food and nutrition articles for Trouve Publishing Inc. since 2004.