Risk factors for osteoporosis in men.

We evaluated the risk factors for osteoporosis in men. The subjects of this study consisted of 686 healthy middle-aged (40-59 years) men who had undergone bone mineral density (BMD) measurement and medical examination, including physical strength. BMD of L2-4 was measured at the anterior-posterior position, using dual X-ray absorptiometry. Physical investigations, such as height, weight, and physical strength, were carried out on the examination day. Details of tobacco and alcohol consumption, exercise, and food intake were described on a questionnaire completed by the subjects. Sixty-five (9.5%) of the 686 subjects had a BMD less than 2.5 SD below the peak bone mass (PBM), 182 (26.5%) had a BMD between 1 SD and 2.5 SD below the PBM; and 439 (64.0%) had a BMD no less than 1 SD below the PBM. Body mass index (BMI) and leg strength were significant positive determinants of BMD, and smoking was a significant negative determinant on multiple regression analysis, with a coefficient of determination of 9.5%. Calcium intake, exercise, and alcohol consumption were not significant determinants of BMD. These results suggest that poor lifestyle behaviors (i.e., smoking) accelerate the reduction of bone density.