Green tea, other teas and coffee consumption and risk of death from chronic kidney disease as the underlying cause among Japanese men and women: the JACC Study.

BACKGROUND

To explore the associations of green tea, coffee, black tea, and oolong tea consumption with mortality from chronic kidney disease (CKD) as the underlying cause among Japanese adults.

METHODS

We conducted a prospective cohort study of 110,585 men and women aged 40-79 years at recruitment from 1986 to 1990. Baseline information on the consumption of tea and coffee, lifestyles, and medical histories was obtained via self-administered questionnaires. We used multivariable Cox regression models to estimate sex-specific hazard ratios and 95% CIs of mortality from CKD associated with the consumption of green tea, coffee, black tea, or oolong tea.

RESULTS

After a median 19-year follow-up, the hazard ratios of mortality from CKD in women were 0.49 (95% CI, 0.22-1.06) for 1-2 cups of green tea per day, 0.56 (0.31-0.99) for 3-4 cups per day, and 0.55 (0.32-0.93) for ≥5 cups per day, compared with <1 cup per day. No such association was found in men. Coffee, black tea, and oolong tea consumption were not associated with CKD risk in either sex.

CONCLUSIONS

Daily consumption of green tea was associated with a lower risk of mortality from CKD in women.