Epidemiological evidence of increased bone mineral density in habitual tea drinkers.
BACKGROUND
Researchers have hypothesized that bone mineral density (BMD) may be influenced by chemical compounds such as caffeine, phytoestrogen, fluoride, and many compounds that are contained in tea extracts. Hence, the relationship between habitual tea consumption and BMD is an interesting issue.


METHODS
Based on an epidemiological survey, we enrolled 497 men and 540 women, 30 years and older, in our study. All subjects were questioned about their habit of tea consumption and other lifestyle characteristics by means of a structured questionnaire. Dual-energy x-ray absorptiometry was used to measure the BMD of the total body, lumbar spine (L1-L4), hip neck, and Ward triangle regions.


RESULTS
Five hundred two subjects (48.4%) were habitual tea drinkers, with a mean duration of tea consumption of approximately 10 years. Compared with nonhabitual tea drinkers, subjects with habitual tea consumption of 6 to 10 years showed higher lumbar spine BMDs, and those with consumption of more than 10 years showed the highest BMDs of all measured regions. Under the multiple stepwise regression models, sex, age, body mass index, total physical activity, and habit of tea consumption were the major significant variables for the different BMD regions. Regarding the behavioral characteristics of tea consumption, the duration of tea consumption was the only independent determinant for the BMDs.


CONCLUSIONS
Habitual tea consumption, especially for more than 10 years, has significant beneficial effects on BMD of the total body, lumbar spine, and hip regions in adults.
Wu
Chih-Hsing
CH
Department of Family Medicine, National Cheng Kung University Hospital, 138 Sheng-Li Rd, Tainan 70428, Taiwan. em75210@email.ncku.edu.tw
Yang
Yi-Ching
YC
Yao
Wei-Jen
WJ
Lu
Feng-Hwa
FH
Wu
Jin-Shang
JS
Chang
Chih-Jen
CJ
D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density; D016021:Epidemiologic Studies; D005260:Female; D006615:Hip / Q000000981:diagnostic imaging; D006801:Humans; D008019:Life Style; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D013662:Tea
D013662:Tea