Hypercholesterolemia is associated with an increased risk of heart disease. The effect of garlic on blood lipids has been studied in numerous trials and summarized in meta-analyses, with conflicting results. This meta-analysis, the most comprehensive to date, includes 39 primary trials of the effect of garlic preparations on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides. The findings suggest garlic to be effective in reducing total serum cholesterol by 17 ± 6 mg/dL and low-density lipoprotein cholesterol by 9 ± 6 mg/dL in individuals with elevated total cholesterol levels (>200 mg/dL), provided garlic is used for longer than 2 months. An 8% reduction in total serum cholesterol is of clinical relevance and is associated with a 38% reduction in risk of coronary events at 50 years of age. High-density lipoprotein cholesterol levels improved only slightly, and triglycerides were not influenced significantly. Garlic preparations were highly tolerable in all trials and were associated with minimal side effects. They might be considered as an alternative option with a higher safety profile than conventional cholesterol-lowering medications in patients with slightly elevated cholesterol.