High calcium intakes are thought to be associated with strong bones and lower risk of fractures. However, findings from epidemiologic studies have not been consistent. In addition, the vast majority of such studies were conducted among women, leading to a relative lack of data concerning men. The objective of this study therefore was to investigate the relation between adult calcium intake and risk of fractures among men in the Health Professionals Follow-up Study (HPFS). During 331,234 person-years of follow-up over an 8-y period, 201 forearm and 56 hip fractures due to low or moderate trauma were reported among 43,063 men 40-75 y of age in 1986 when they first completed a questionnaire about diet and lifestyle factors. After controlling for age, smoking status, body mass index (BMI), physical activity, alcohol consumption and total energy intake, the relative risk (RR) of forearm fractures for men in the highest quintile of calcium intake (from foods plus supplements) compared with those in the lowest quintile was 0.98 [95% confidence interval (CI) = 0.59-1.61; P for trend = 0.78]; for hip fractures, the comparable RR was 1.19 (95% CI = 0.42-3.35; P for trend = 0.58). Relative risks for consuming >2.5 glasses (600 mL) of milk per day compared with one (240 mL) or fewer per week were 1.06 (95% CI = 0.69-1.62; P for trend = 0.82) for forearm fractures and 0.97 (95% CI = 0.39-2.42; P for trend = 0.56) for hip fractures. In conclusion, these results do not support a relation between calcium intake and the incidence of forearm or hip fractures in men.