title: Dietary diversity and 14-year decline in higher-level functional capacity among middle-aged and elderly Japanese.
abstract: OBJECTIVE
  This study aimed to clarify the effects of dietary diversity on a decline in higher-level functional capacity among middle-aged and elderly subjects in Japan.
  
  
  METHODS
  Data were derived from the National Institute for Longevity Sciences - Longitudinal Study of Aging. Subjects comprised 1317 men and women aged 40 to 79 at baseline (1997-2000) who participated in a follow-up postal survey (2013). Higher-level functional capacity was measured using the Tokyo Metropolitan Institute of Gerontology index of competence (total score and 3 subscales). Dietary intake was assessed using a 3-d dietary record, and dietary diversity was determined using the Quantitative Index for Dietary Diversity (QUANTIDD). The odds ratios and 95% confidence intervals (CI) for a decline in higher-level functional capacity in the follow-up study according to quartiles of QUANTIDD at baseline were estimated, controlling for age, sex, higher-level functional capacity scores at baseline, body mass index, alcohol consumption, physical activity, depressive score, household income, education, smoking, and disease history.
  
  
  RESULTS
  A total of 214 (16%), 145 (11%), 70 (5%), and 136 (10%) subjects showed a decline in total score for higher-level functional capacity (≥2), instrumental self-maintenance (≥1), intellectual activity (≥2), and social role (≥2), respectively. Multivariate-adjusted odds ratios (95% confidence intervals) for the score for intellectual activity decline according to the lowest through highest quartiles of QUANTIDD were 1.00 (reference), 0.47 (0.23-0.95), 0.44 (0.22-0.90), and 0.41 (0.20-0.83), respectively (P for trend = 0.06).
  
  
  CONCLUSIONS
  Daily intake of various foods may protect against a decline in intellectual activity among middle-aged and elderly community dwellers in Japan.
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan. Electronic address: otsuka@ncgg.go.jp.
authors.forename: Rei
authors.initials: R
authors.lastname: Otsuka
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan; Faculty of Health and Medical Sciences, Aichi Shukutoku University, Aichi, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kato
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Nishita
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan.
authors.forename: Chikako
authors.initials: C
authors.lastname: Tange
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan; Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Nakamoto
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan; Research Fellow of the Japan Society for the Promotion of Science, Japan.
authors.forename: Makiko
authors.initials: M
authors.lastname: Tomida
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan; Faculty of Human Life and Science, Doshisha Women's College of Liberal Arts, Kyoto, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Imai
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan; Faculty of Health and Medical Sciences, Aichi Shukutoku University, Aichi, Japan.
authors.forename: Fujiko
authors.initials: F
authors.lastname: Ando
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan; Graduate School of Nutritional Sciences, Nagoya University of Arts and Sciences, Aichi, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shimokata
authors.affiliation: National Center for Geriatrics and Gerontology, Aichi, Japan; Institute of Gerontology, Oberlin University, Tokyo, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D003072:Cognition Disorders / Q000453:epidemiology*; D004032:Diet / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D015577:Geriatric Assessment / Q000379:methods / Q000706:statistics & numerical data*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged
keywords: Community dwellers; Dietary guidelines; Food variety; Intellectual activity; Japan; Public health nutrition