Bone scans reveal that adults who drink tea at moderate frequency have more favorable bone mineral density (BMD) compared to those who do not, according to a group in China.
The finding is from researchers from Southern Medical University and Sun Yat-sen University in Guangzhou, China, who examined the relationship between tea consumption frequency and longitudinal bone mineral changes over 13 years among a group of 1,708 community-dwelling adults.
“Moderate-frequency tea consumption was associated with better bone mineral status and more favorable longitudinal changes,” according to the group. The study was published August 10 in The American Journal of Clinical Nutrition.
Tea is among the most widely consumed beverages globally, and prior research has suggested that its polyphenol content, particularly flavan-3-ols, may benefit bone health, the authors noted. However, most prior evidence has relied on cross-sectional designs without repeated bone mineral assessments or objective biomarker confirmation of tea intake, limiting conclusions about longitudinal effects, they added.
To bridge the gap, the group enrolled 1,708 community-dwelling adults in the Guangzhou Nutrition and Health Study (GNHS), a prospective cohort with four assessment visits using dual-energy x-ray absorptiometry (DEXA) over 13 years. Tea consumption frequency was categorized as non- (0 times/week), low- (1 to 6 times/week), moderate- (7 times/week), or high- (> 7 times/week). The primary outcomes were sex-specific bone mineral density (BMD) and bone mineral content (BMC) Z-scores.
The researchers found that bone mineral trajectories diverged significantly between tea consumption groups over the 13-year follow-up, with differences observed for whole-body, lumbar spine, and femoral neck BMD and whole-body BMC. Moderate-frequency tea drinkers had the highest visit-averaged adjusted marginal mean Z-scores across bone sites: 0.107 for whole-body BMD, 0.090 for lumbar spine BMD, and 0.108 for femoral neck BMD.
“These findings suggest that habitual tea consumption and circulating flavan-3-ol concentrations may be related to bone health,” the authors wrote.
The group noted that the study did not establish an optimal level of tea intake and that further studies incorporating repeated biomarker measurements and more detailed assessments of tea intake, dose, and preparation methods are warranted.
Read the full study here.