Smoking, high blood pressure, and diabetes are known risk factors for the fatty thickening and hardening of the arteries known as atherosclerosis.

A study involving 280 patients assessed the influence of garlic on arterial wall thickness/plaque buildup, an established indicator of atherosclerosis. Patients were randomly assigned to a group that received garlic supplementation (900 milligrams of garlic powder daily) or a placebo group that received a harmless tablet containing no garlic powder.

More than half of the patients completed the 48-month study (61 in the garlic group, 91 in the placebo group), at which time sonographic measurements were recorded and compared with baseline measurements.

Results: Continuous intake of high-dose garlic powder reduced the increase in arterial plaque volume by 6-18% compared with the placebo group, and seemed to cause a slight reduction over the 48-month study period. Specifically, plaque volume increased by 15.6% in the placebo group but decreased by 2.6% in the garlic group. The authors suggest that “not only a preventive but perhaps a curative role in plaque regression may be ascribed to garlic remedies.”