Relationship between chewing ability and high-level functional capacity in an 80-year-old population in Japan

Objectives: To evaluate the association between high-level functional capacity and chewing in a middle-old community-based population. Background: Although basic and instrumental activities of daily living are known to be associated with chewing ability in the elderly, an association between higher levels of competence and chewing ability has not been evaluated in the elderly. Materials and methods: The association between chewing ability using a number of different foods and high-level functional capacity by the Tokyo Metropolitan Institute of Gerontology was evaluated in 694, 80-year-old people residing in Fukuoka Prefecture, Japan. Results: A significant correlation was found, using multiple regression or logistic regression analyses adjusted for various confounding factors, between the number of total chewable foods, hard foods or moderately hard foods, and total functional capacity, instrumental activity, intellectual activity or social role ability. In contrast, the number of slightly hard foods, easily chewable foods and remaining teeth were only partly related to total functional capacity and intellectual activity. Conclusion: High-level functional capacity including intellectual activity and social role in middle-old elderly was associated with the ability to chew hard foods than to chew easily chewable foods. Maintenance of chewing ability in elderly might result in better intellectual activity and social role.