Oolong tea drinking boosts calcaneus bone mineral density in postmenopausal women: a population-based study in southern China

Abstract

Introduction Observational studies have shown that tea consumption has a potentially beneficial effect on bone health. However, few studies have assessed the effects of types of tea consumed on bone health. We aimed to investigate whether drinking oolong tea is associated with increased calcaneus bone mineral density (BMD) in postmenopausal women. Methods From an epidemiological survey in Shantou, 476 postmenopausal women aged 40 to 88 years were enrolled in the study. All women were questioned about their demographic features, lifestyle, health status, types of tea consumed, habit of tea consumption, and habitual dietary intake by use of a structured questionnaire. Estimated areal BMD was measured by calcaneal quantitative ultrasound (QUS). Results As compared with non-tea drinkers, oolong tea drinkers had higher calcaneus BMD (beta 34.70 [95% CI 10.38, 59.03]). In addition, calcaneus BMD was significantly increased for those drinking 1-5 cups/day (beta 27.43 [95% CI 3.70, 51.16]) but not > 5 cups/day. We observed no linear increase in calcaneus BMD with increasing years of tea consumption and local polynomial regression fitting showed a parabola-shaped association between years of tea consumption and calcaneus BMD. However, symptoms of osteoporosis did not differ by types of tea consumed. Conclusion Long-term moderate oolong tea consumption may have beneficial effects on bone health in postmenopausal women in Shantou of southern China.