The influence of body size, smoking, and diet on bone density in pre- and postmenopausal women

We studied the determinants of low bone mineral density, using data from a population-based screening program of osteoporosis carried out among 1,373 women (age 40-64 years) in the province of Pordenone, Italy, by means of dual photon absorptiometry of the lumbar spine. Menopause had a major effect on bone mineral density. Age had little influence before menopause. In multivariate linear regression analyses, weight was the strongest predictor of bone mineral density in pre- as well as postmenopausal women. After the inclusion in a single model of a term for current weight, weight at ages 12 and 30 years explained some additional variance, whereas high waist-to-hip ratio (an indicator of central adiposity) had no influence. Smoking 15 or more cigarettes per day entailed a small increased risk of osteoporosis, but this effect, independent of weight, appeared to be restricted to premenopausal women. No food or micronutrient that we examined was predictive of bone mineral density, nor was coffee or alcoholic beverage intake.