Updated association of tea consumption and bone mineral density

Abstract
Current studies evaluating the association of tea consumption and bone mineral density (BMD) have yielded inconsistent findings. Therefore, we conducted a meta-analysis to assess the relationship between tea consumption and BMD. The PubMed, Embase, and Cochrane Library databases were comprehensively searched, and a meta-analysis performed of all observational studies assessing the association of tea consumption and BMD. Forest plots were used to illustrate the results graphically. The Q-test and I2 statistic were employed to evaluate between-study heterogeneity. Potential publication bias was assessed by the funnel plot. Four cohort, 1 case–control, and 8 cross-sectional studies including a total of 12,635 cases were included. Tea consumption was shown to prevent bone loss [odds ratio (OR): 0.66; 95% confidence interval (CI), 0.47–0.94; P = 0.02], yielding higher mineral densities in several bones, including the lumbar spine [standardized mean difference (SMD): 0.19; 95% CI, 0.08–0.31; P = 0.001], hip (SMD: 0.19; 95% CI, 0.05–0.34; P = 0.01), femoral neck [mean difference (MD): 0.01; 95% CI, 0.00–0.02; P = 0.04], Ward triangle (MD: 0.02; 95% CI, 0.01–0.04; P = 0.001), and greater trochanter (MD: 0.03; 95% CI, 0.02–0.04; P < 0.00001), than the non-tea consumption group. This meta-analysis provided a potential trend that tea consumption might be beneficial for BMD, especially in the lumbar spine, hip, femoral neck, Ward triangle, and greater trochanter, which might help prevent bone loss.