Green tea consumption is associated with lower psychological distress in a general population: the Ohsaki Cohort 2006 Study.
BACKGROUND
Although green tea or its constituents might reduce psychological stress, the relation between green tea consumption and psychological distress has not been investigated in a large-scale study.


OBJECTIVE
Our aim was to clarify whether green tea consumption is associated with lower psychological distress.


METHODS
We analyzed cross-sectional data for 42,093 Japanese individuals aged > or =40 y from the general population. Information on daily green tea consumption, psychological distress as assessed by the Kessler 6-item psychological distress scale, and other lifestyle factors was collected by using a questionnaire. We used multiple logistic regression analyses adjusted for age, sex, history of disease, body mass index, cigarette smoking, alcohol consumption, time spent walking, dietary factors, social support, and participation in community activities to investigate the relation between green tea consumption and psychological distress.


RESULTS
We classified 2774 (6.6%) of the respondents as having psychological distress (Kessler 6-item psychological distress scale > or =13/24). There was an inverse association between green tea consumption and psychological distress in a model adjusted for age and sex. Although the relation was largely attenuated when possible confounding factors were adjusted for, a statistically significant inverse association remained. The odds ratio (with 95% CI) of developing psychological distress among respondents who consumed >/=5 cups of green tea/d was 0.80 (0.70, 0.91) compared with those who consumed <1 cup/d. These relations persisted when respondents were stratified by social support subgroups or by activities in communities.


CONCLUSIONS
Green tea consumption was inversely associated with psychological distress even after adjustment for possible confounding factors.
Hozawa
Atsushi
A
Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan. hozawa-thk@umin.ac.jp
Kuriyama
Shinichi
S
Nakaya
Naoki
N
Ohmori-Matsuda
Kaori
K
Kakizaki
Masako
M
Sone
Toshimasa
T
Nagai
Masato
M
Sugawara
Yumi
Y
Nitta
Akemi
A
Tomata
Yasutake
Y
Niu
Kaijun
K
Tsuji
Ichiro
I
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007564:Japan; D008019:Life Style; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D013315:Stress, Psychological / Q000517:prevention & control* / Q000523:psychology; D011795:Surveys and Questionnaires; D013662:Tea / Q000502:physiology*
D013662:Tea