Consumption of Green Tea is Associated with Reduced Risk of Cognitive Decline
M. Shinohara et al.
International Conference on Alzheimer's and Parkinson's Disease Presented March 19, 2015.
Objectives
We aimed to determine whether the consumption of green tea, coffee, or black tea is associated with the incidence of dementia and mild cognitive impairment (MCI) in the general population.
Methods
We conducted a population-based prospective study with Japanese residents aged >60 years from Nakajima, Japan (the Nakajima Project). Participants received an evaluation of cognitive function and blood tests. The consumption of green tea, coffee, and black tea was also evaluated at baseline.
Results
Of 723 participants with normal cognitive function at a baseline survey (2007-2008), 490 completed the follow up survey in 2011-2013. The incidence of dementia during the follow-up period (mean ± SD: 4.9 ± 0.9 years) was 5.3%, and that of MCI was 13.1%. With regard to the incidence of dementia, multiple-adjusted odds ratio was 0.26 (95% CI: 0.06–1.06) for consuming green tea every day compared with those who did not consume green tea at all. Regarding the incidence of cognitive decline (dementia or MCI), multiple-adjusted odds ratio was 0.32 (95% CI: 0.16–0.64) among individuals who consumed green tea every day and 0.47 (95% CI: 0.25–0.86) among those who consumed green tea 1–6 days per week compared with individuals who did not consume green tea at all.
No association was found between coffee or black tea consumption and the incidence of dementia or MCI.
Conclusions
Higher green tea consumption was associated with lower incidence of cognitive decline (dementia or MCI), even after adjustment for possible confounding factors.
Green Tea Linked to Lower Risk for Cognitive Decline