This cross-sectional study evaluated the association between daily calcium intake and body mass index (BMI) in 647 subjects from Reus, Spain. 261 men and 313 women, aged 18 to 70 years, were randomly selected from the population census. Food intake was quantified by the 24-hour recall method, for three non-consecutive days including one holiday. Weight and height were measured. The study sample was divided into quartiles of calcium intake adjusted for age, energy, and total fat and fiber intake in both men and women. Average calcium intake was low (557.6 +/- 234.0 mg/day). Calcium intake was significantly (p < 0.0001) and positively associated with energy intake (r = 0.50 for men; r = 0.49 for women; p < 0.0001) and dietary fiber consumption (r = 0.27 for men; r = 0.25 for women; p < 0.0001). After adjusting for age, energy intake, fat intake, and dietary fiber, the odds ratio of being in the highest quartile of BMI was significantly reduced in the highest quartile of calcium intake [men: 0.63 (0.30-1.29); women: 0.36 (0.17-0.79)] compared to the lowest quartile in both sexes. We conclude that our study showed a negative relationship between calcium intake and BMI in a Mediterranean community.