Objective: To examine whether the relation between lifestyle and metacarpal bone mineral density (BMD) varied with life-stages. Design: Cross-sectional study. Setting: Taking questionnaires related to lifestyle and examining metacarpal BMD by computed X-ray densitometry at a local health care center. Subjects: Out of 750 Japanese women aged 40 ± 69 y old who underwent screening for osteoporosis, we selected 535 healthy subjects without medical conditions or lifestyle factors known to affect bone metabolism. Results: A cross-sectional comparison of BMD and years since menopause (YSM) resulted in a logarithmic regression model (BMD 2.539 ± 0.1496log e YSM, r 2 0.418), indicating that a prominent reduction in metacarpal BMD appears up to 4 ± 6 y after menopause. In premenopausal women with regular menstruation, those who engaged in regular physical activity during adolescence showed signi®cantly greater BMD than those who did not. In 1 ± 5-y postmenopausal women, those with current calcium intake of more than 800 mgad, current milk intake greater than 900 mlaweek, daily consumption of milk andaor dairy products, or frequent consumption of small ®sh showed signi®cantly greater BMD. In 6 ± 15-y postmenopausal women, those who took more than 6000 or 8000 stepsaday showed signi®cantly greater BMD. Conclusions: The relation between lifestyle and BMD differed with life-stages in Japanese women. It was suggested that to perform lifestyle modi®cations for the prevention of osteoporosis, life-stages should be taken into consideration.