ABSTRACT
In order to explore the risk factors of osteoporosis , a 1:1 matched case-control study was conducted on 157 pairs of intellectuals with age above 40 years. Bone mineral density of distal radius was measured using single photon absorptiometry and radiograph of calcaneus was classified according to Jhamaris's method.Multivarious factors related to diet, physical exercise, tea drinking, smoking,menstrual and reproductive history were significantly associated with osteoporosis. In a multiple conditional logistic regression model, low calcium intake, exercise index before 40 years of age, average time of exercise per week above 40 years old, tea consumption, and the number of years after menopause in women were the most important and predictive factors. The risk led by lower calcium intake was higher in women than in men. The risk due to lack of regular exercise was more prominent in men,but for both sexes lack of exercise in early years of life was more risky than that in later years. As many people have habit of excessive tea drinking, the exact effect of tea on osteoporosis deserves further study.