The Truth About Your Garlic Supplement

Is garlic cholesterol's natural enemy? This definitive study of garlic sandwiches and garlic pills says no way.


Is garlic cholesterol's natural enemy? This definitive study of garlic sandwiches and garlic pills says no way.

“Supports your cardiovascular system,” say the Kyolic bottles. “Cholesterol’s Natural Enemy,” boast the Garlique packages.

Sounds like taking garlic supplements keeps heart disease at bay. Not so fast. People have been eating or using garlic for hundreds of years, trying to ward off everything from gangrene and the plague to vampires.

And they’ve been taking garlic pills since the 1980s to lower their cholesterol.

In a 2007 study, Christopher Gardner, an associate professor of medicine at Stanford University, put raw garlic and two popular garlic-pill formulations to a rigorous long-term test in 192 adults with moderately high LDL (“bad”) cholesterol. Supplement manufacturers market garlic in a dizzying array of formulations.

“But the compounds that end up in garlic oil, aged garlic, and garlic powder, for example, wouldn’t necessarily be the same compounds or amounts or proportions that are in fresh garlic,” explains Gardner. So his team randomly assigned roughly a quarter of the participants to eat four grams (around 1½ teaspoons) a day of raw garlic. Another quarter were given Garlicin (powdered garlic) pills, while a quarter got Kyolic (aged garlic) pills and a quarter were told to take a placebo.

(The garlic-pill takers were given enough Garlicin or Kyolic to match the active compounds in the raw garlic.)

No matter how hard the researchers tried—they mixed the raw garlic into sandwiches—the raw-garlic eaters could tell which group they were in. “Our garlic pills, however, were successfully blinded,” notes Gardner. After six months, LDL cholesterol, HDL (“good”) cholesterol, and triglycerides were no different in the garlic eaters and the garlic-pill takers than in those who got the placebo.

“The backlash we got when we published our study! I must have had 50 offers from supplement companies of, ‘Hey! I know why your study didn’t work. You didn’t use my pill,’ ” recalls Gardner.

“But the industry, they want to sell pills. I wouldn’t buy any of these supplements to lower my blood cholesterol.”

Bottom Line: Leave the garlic pills on the shelf. If your LDL cholesterol is above “optimal” (if it’s 100 or more), cut calories (if you need to lose weight), exercise more, and eat a healthy OmniHeart diet. In any case, talk to your doctor about whether you should take a statin or other drug to lower your LDL level.

Source: Arch. Intern. Med. 167: 346, 2007