Tea consumption may decrease the risk of osteoporosis: an updated meta-analysis of observational studies

Several epidemiological investigations have evaluated the correlation between tea consumption and risk of osteoporosis, but the results are inconsistent. Therefore, we conducted an updated meta-analysis of observational studies to assess this association. We searched for all relevant studies including cohort, cross-sectional, and case-control studies published from database inception to July 15, 2016, using MEDLINE EMBASE, and Cochrane Library. Polled odds ratios (ORs) were calculated using the random-effect model. Fourteen articles (16 studies) that examined 138 523 patients were included in this meta-analysis. Seven studies concerning bone mineral density (BMD) showed an increase in BMD with tea consumption, including 4 cross-sectional studies (OR, 0.04, 95% confidence interval [CI], 0.01-0.08) and 3 cohort studies (OR, 0.01; 95% CI, 0.01-0.01). The remaining 9 studies concerning fracture, including 6 case-control studies and 3 cohort studies, showed no association between tea consumption and osteoporotic fracture (OR, 0.86; 95% CI, 0.74-1.01). This updated meta-analysis demonstrates that tea consumption could increase BMD, but the association with osteoporotic fracture requires further investigation. Together, the results highlight the need for future, high-quality designed clinical trials on tea consumption and osteoporosis. (C) 2017 Elsevier Inc. All rights reserved.