January 2000, Volume 54, Issue 1, Pages 9 - 13

Original Communication

Relation of lifestyle factors to metacarpal bone mineral density was different depending on menstrual condition and years since menopause in Japanese women K Ishikawa1, T Ohta1, M Hirano1, K Yoshimoto2, S Tanaka2 & S Inoue3 1Division of Health Promotion, National Institute of Health and Nutrition, Tokyo, Japan     2Health Care Center of Oharu Town, Aichi, Japan     3Division of Geriatric Health Science, National Institute of Health and Nutrition, Tokyo, Japan     Correspondence to: K Ishikawa , Division of Health Promotion, National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku, Tokyo 162-8636, Japan. E-mail: kazu@nih.go.jp.      Guarantors: KI and TO. Contributors: KI was the lead investigator and wrote the paper. TO was the medical supervisor. MH undertook the nutritional assessment and performed data analyses. KY managed the screening for osteoporosis. ST conducted the lifestyle questionnaire. SI participated in drafting and editing the paper. All investigators were involved in the study design.

Keywords

bone mineral density;   menstruation;   menopause;   dietary calcium;   exercise;   walking

Abstract

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=2.539-0.149×loge YSM, r2=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 significantly greater BMD than those who did not. In 1-5-y postmenopausal women, those with current calcium intake of more than 800 mg/d, current milk intake greater than 900 ml/week, daily consumption of milk and/or dairy products, or frequent consumption of small fish showed significantly greater BMD. In 6-15-y postmenopausal women, those who took more than 6000 or 8000 steps/day showed significantly greater BMD. Conclusions: The relation between lifestyle and BMD differed with life-stages in Japanese women. It was suggested that to perform lifestyle modifications for the prevention of osteoporosis, life-stages should be taken into consideration. Sponsorship: Grant for Research on Health Service from Ministry of Health and Welfare, Japan and grant from The National Dairy Promotion and Research Association of Japan. European Journal of Clinical Nutrition (2000) 54, 9-13

Received 23 February 1999; Revised 6 July 1999; Accepted 16 July 1999

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