Garlic Can't Scare Away Cholesterol

B O S T O N, Sept. 19, 2000 -- Garlic may scare away vampires, but its powers apparently don’t extend to chasing away cholesterol.

The aromatic spice that many hoped would cut their cholesterol levels as a pill or as a pizza topping has a negligible effect, according to a comprehensive review of the research.

Researchers at Britain’s University of Exeter have re-examined 13 studies that previously looked at whether garlic could help patients with elevated cholesterol levels. Their conclusion? For this population, sniff researchers, using garlic is of “questionable value.”

The medicinal use of garlic dates back to ancient times. More recently,garlic has been hailed as the “aspirin of the ’90s” ever since early studies linked it to blood-thinning and cholesterol-lowering properties.

Researchers noticed impressive longevity in populations with garlic-heavy diets decades ago, leading to the hypothesis that garlic’s active ingredient, allicin, might play a role in lowering high cholesterol levels, a marker for future heart disease.

Early research seemed to back this up, and two comprehensive reviews completed in the mid-’90s, known as “meta-analyses,” or investigations that analyze data compiled from already published studies, seemed to confirm that garlic reduced cholesterol levels by at least 9 percent to as much as 12 percent.

Research Called Foul But some scientists criticized the research, saying the poor quality of the included studies cast a foul odor on the results. Since then, several major follow-up studies have failed to find significant benefits of garlic on cholesterol levels.

Now, this meta-analysis of more current research, published in the current issue of the Annals of Internal Medicine, yet again confirms those poor results, finding that garlic produced only a 5 percent average drop in cholesterol levels, at best.

And when looking at the half dozen studies the researchers considered most reliable, the effect vanished completely.

“The size of the effect is modest,” wrote lead author Dr. Edzard Ernst, a professor of complementary medicine at the University of Exeter. “Garlic is not an efficient way to decrease total serum cholesterol level.”

“Garlic is a dead issue,” confirms Dr. Sidney Alexander, director of the lipid clinic at the Lahey Clinic Medical Center in Burlington, Mass. “No one recommends it anymore.”

Sales Have Nosedived Indeed, sales of garlic supplements have taken a nosedive in recent years, dropping 28 percent, from $223 million in 1997 to $174 million last year, reports the Nutrition Business Journal, a San Diego-based market research and publishing firm.

One reason may be that garlic compares poorly with other proven dietary methods for reducing high cholesterol levels, says Dr. Nilo Cater, an assistant professor of nutrition and preventive cardiology at University of Texas Southwestern Medical Center in Dallas.

Fiber has been proved to reduce cholesterol levels by around 6 percent to 8 percent; soy protein, such as soy milk or tofu, by 7 percent to 10 percent; and the new cholesterol-lowering margarine spreads such as Benecol, by 10 percent to 20 percent, he says.

Finally, the popular group of cholesterol-lowering medications known as statins have been shown to reduce cholesterol levels from 17 percent to 32 percent, the article reports.

But garlic proponents say that even an effect as small as 5 percent should not be discounted.

Don’t Discount Small Amount “The test of time shows that garlic does work,” says Dr. Stephen Warshafsky, an associate professor of medicine at New York Medical College in Valhalla, N. Y., who conducted one of the earlier meta-analyses. “It’s a small but probably real effect.”

“Of course it’s not a great drug,” he adds. “If you want to lower your cholesterol levels by 20 percent, use a statin. But if your cholesterol is a little high, it’s a wonderful thing to know there are things you eat that can keep you healthy.”

There is also some evidence that garlic has some other health benefits, such as helping lower blood pressure and acting as a blood thinner, he says, although patients already on blood-thinning medications should be careful of gorging on garlic.

Fresh is Best? Garlic enthusiasts also believe the studies may not show garlic’s true effects because they looked mainly at garlic in pill form. They suspect the herb somehow loses its potency when processed into pills and powders, and may be most therapeutic when eaten fresh from the clove.

“Probably, incorporating a clove of fresh garlic a day into your food would be the ultimate use,” Warshafsky says.

Doctors concede fresh garlic may be more vital, but no one knows for sure.

“Until someone does a study using the real stuff, rather than oils or powders,” sighs Lahey’s Alexander, “this issue will never be laid to rest.”