Hundreds of studies suggest the answer is yes, but the data is hard to interpret because some studies are sponsored by manufacturers of garlic extracts, sold as dietary supplements, while others simply track health outcomes in people who do, or don’t, eat lots of garlic.

In October, 2000, a government report by the Agency for Healthcare Research and Quality found that while garlic may lower some types of cholesterol in the short term, it did not appear to offer long-term protection against cardiovascular disease. The study also found no evidence that garlic had a beneficial impact on blood pressure or diabetes.

On the other hand, a randomized, double-blind clinical trial of 152 people in 1999 by German researchers found that over four years, those taking the supplement Kwai showed less buildup of plaque in their arteries than those not on the pills.

Another randomized, double-blind study of 19 people by researchers at the Harbor-UCLA Medical Center used a different supplement, Kyolic. Dr. Matthew Budoff, a cardiologist and the lead researcher, said the 2004 study suggested that the extract slows progression of calcification, a marker of plaque, in coronary arteries.

As for cancer, the National Cancer Institute says on its website that “a host of studies provide compelling evidence that garlic” can slow the cancer process, particularly for cancers of the stomach and prostate. But the studies were mostly simple correlations between garlic intake and cancer – not true experiments showing that garlic caused the reduction in cancer.

Mark Blumenthal, executive director of the American Botanical Council, a Texas-based, nonprofit group supported by the herbal industry, the government and health professionals, said the chemistry of garlic is so complex that it’s hard to extrapolate from research on supplements, which differ among themselves, into recommendations for consuming raw or cooked garlic.

Cooking destroys many of the chemicals with potential medicinal value. To get some health benefits from raw garlic, he said, you have to eat one to two raw cloves a day. No problem for me – I love the stuff.