Findings from animal and human studies suggest an association between low cholesterol levels and suicidal behaviors. The purpose of this case-control study was to test whether cholesterol levels in suicide attempters are lower than in controls without suicide attempt history matched by gender, age, and body mass index (BMI). Suicide attempters (n=177: 68 men and 109 women) and controls (177 blood donors) were assessed. Serum cholesterol levels were significantly lower in suicide attempters than in controls. After gender stratification, the difference remained significant in men, but not in women.