Background: The beneficial effect of 3-hydroxy-3-methylglutyaryl co-enzyme A reductase inhibitors on cardiovascular risk reduction has been clearly established. Concerns have been raised that lowering blood cholesterol by other hypolipidemic drugs or by a non-pharmacologic approach may have deleterious effects on psychopathologic parameters. Garlic is one of the most commonly used herbal remedies and is considered to have hypocholesterolemic as well as other cardio-protective properties. Its effect on psychopathologic parameters has never been reported.

Objectives: To evaluate the effect of garlic on lipid parameters and depression, impulsivity, hostility and temperament in patients with primary type 2 hyperlipidemia.

Methods: In a 16 week prospective double-blind placebo-controlled study, 33 patients with primary hypercholesterolemia and no evidence of cardiovascular disease were randomly assigned to receive either garlic or placebo. Garlic in the form of alliin 22.4 mg/day was given to 13 patients, and placebo to 20. Both groups received individual dietary counseling. The changes in lipid profile and the various psychopathologic parameters were determined at the beginning and end of the trial. The differences in lipid parameters were evaluated by Student’s t-test. The psychological data were analyzed by one-way analysis of variance (ANOVA) with repeated measures and Neuman-Keuls test.

Results: No significant changes were observed in levels of total cholesterol, low density lipoprotein-cholesterol, high density lipoprotein-cholesterol and triglycerides, or in the psychopathologic parameters evaluated.

Conclusion: Short-term garlic therapy in adults with mild to moderate hypercholesterolemia does not affect either lipid levels or various psychopathologic parameters.