Can garlic reduce levels of serum lipids? A controlled clinical study

To assess the effects of standardized garlic powder tablets on serum lipids and lipoproteins, glucose, and blood pressure.

Forty-two healthy adults (19 men, 23 women), mean age of 52 +/- 12 years, with a serum total cholesterol (TC) level of greater than or equal to 220 mg/dL received, in a randomized, double-blind fashion, either 300 mg three times a day of standardized garlic powder in tablet form or placebo. Diets and physical activity were unchanged. This study was conducted in an outpatient, clinical research unit.

The baseline serum TC level of 262 +/- 34 mg/dL was reduced to 247 +/- 40 mg/dL (p < 0.01) after 12 weeks of standard garlic treatment. Corresponding values for placebo were 276 +/- 34 mg/dL before and 274 +/- 29 mg/dL after placebo treatment. Low-density lipoprotein cholesterol (LDL-C) was reduced by 11% by garlic treatment and 3% by placebo (p < 0.05). There were no significant changes in high-density lipoprotein cholesterol, triglycerides, serum glucose, blood pressure, and other monitored parameters.

Treatment with standardized garlic 900 mg/d produced a significantly greater reduction in serum TC and LDL-C than placebo. The garlic formulation was well tolerated without any odor problems.