Study Crushes Garlic's Claim to Lower Cholesterol

MONDAY, Feb. 26 (HealthDay News) -- For those enduring bad breath for the sake of good cardiovascular health, a new study brings bad news: Garlic doesnotlower LDL, the so-called "bad cholesterol."

The finding, reported in the Feb. 26 issue of theArchives of Internal Medicine, applies to both fresh garlic and popular garlic supplements.

"We did a bigger and better trial than has ever been done before and with NIH (National Institutes of Health) funding, not with supplement-manufacturer funding. And as far as lowering cholesterol, garlic didn't work," said Christopher D. Gardner, study lead author and nutrition scientist and assistant professor with the Stanford Prevention Research Center in Stanford, Calif.

Too much low-density lipoprotein (LDL) cholesterol in arteries is known to elevate risks for stroke or heart attack. Typically, patients with LDL levels below 130 mg/dl are considered to be in the healthy range.

The notion that garlic is one of nature's answers to all sorts of serious ills stretches as far back as Egypt, circa 1500 B.C., experts say.

More recent interest in garlic's specific potential as an LDL-lowering agent stems from lab work and animal testing done over the past few years. That data suggested that crushing garlic produces a sulfur-containing compound, allicin, that might block cholesterol synthesis.

To test that theory, Gardner's team analyzed the impact of garlic and garlic supplements on LDL blood levels in 192 men and women between the ages of 30 and 65. All of the study participants had moderately high LDL cholesterol readings that averaged out at about 140 mg/dl.

The researchers focused on this moderate-level group, because they assumed that those with more severely elevated LDL would be taking prescription drugs, such as statins, that could confound the results. By contrast, patients with moderate elevations were more likely to combat the problem with supplements alone.

Pregnant women, smokers, those with heart disease, cancer, or diabetes, and current users of high blood pressure or lipid-lowering medications were excluded from the study.

Six days a week for six months, all the participants ingested the equivalent of a four-gram clove of garlic in one of three forms: either mixed into a sandwich in raw form or as one of two popular commercially-available supplements, Garlicin and Kyolic-100.

The authors pointed out that the two chosen supplements are manufactured differently, with Garlicin being a powdered option that is the only brand so far to have demonstrated an ability in lab studies to produce a consumable amount of allicin equivalent to raw crushed garlic.

By contrast, Kyolic is an aged-garlic extract specifically designed to reduce bad breath side-effects in users. This option was described by the authors as "one of the most popular brands on the market" and is the only supplement to have been previously tested for cholesterol-lowering abilities in more than one clinical trial.