Does Japanese diet prevent brain atrophy in cognitively normal individuals: a 10-years cohort study of middle-aged and elderly dwelling Japanese

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K22175
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0108:Sociology and related fields
• Research Institution: National Center for Geriatrics and Gerontology
• Principal Investigator: Zhang Shu 国立研究開発法人国立長寿医療研究センター, 老年学・社会科学研究センター, 研究員 (00874471)
• Project Period (FY): 2020-09-11 – 2022-03-31
• Keywords: Japanese diet / MRI / brain atrophy / hippocampus / transverse temporal

Outline of Final Research Achievements

The present study uses the 3-day dietary record(3DR) data and the 3D brain magnetic resonance imaging (MRI) images during a 10-year follow-up to elucidate (1) whether Japanese diet suppresses the total brain atrophy in cognitively normal individuals, and (2) which part(s) of the brain is affected.
The results of the study (with 2-years follow-up) showed that green tea, one of the important components of the Japanese diet, exhibited an inhibitory effect on hippocampal atrophy. In addition, we observed a negative association between Japanese dietary pattern evaluated using a 9-component weighted Japanese Diet Index score and annual change ratio of transverse temporal. These findings suggest that the Japanese diet may have a positive effect in inhibiting brain atrophy in middle-aged and elderly Japanese community-dwellers.

Free Research Field

Nutritional epidemiology

Academic Significance and Societal Importance of the Research Achievements

By using 2-years' follow-up data, the present study elucidated the impact of Japanese diet on brain atrophy at an earlier disease stage of dementia, suggesting the possibility of preventing dementia by improving diet in daily life.