The effects of diet and life-style on bone mass in women.

Osteoporosis is characterized by a reduction in bone density. The majority of Caucasian women are at risk for osteoporosis-related fractures, especially in the wrist, spine, and hip. The degree of fracture risk at a specific bone site is best assessed by measuring the density of the bone with single- and dual-photon absorptiometry or with computed tomography. Bone density in women at any adult age is quite variable. Numerous diet and life-style factors are thought to influence bone density and, in turn, fracture risk. Strong evidence exists for a relationship between bone density and amenorrhea, body weight, alcoholism, smoking, and inactivity. In contrast, conflicting or insufficient evidence exists for a relationship with dietary protein, phosphorus, caffeine, and calcium intake. To minimize fracture risk, young women should have regular menses, consume a nutritionally adequate diet, perform regular physical activity, and, probably, use fluoridated water. When immediately postmenopausal, women should seriously consider estrogen replacement, since osteopenia is the rule, rather than the exception, in old age.