Hardness of the habitual diet and its relationship with cognitive function among 70-year-old Japanese elderly

Findings from the SONIC Study

SONIC Study Group

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Background: There is increasing evidence of causal links between poor mastication and cognitive impairment, but possible effects of dietary hardness, which clearly affects mastication, on cognitive function are unknown. Objective: We investigated the hypothesis that hardness of the habitual diet would be associated with cognitive function among older Japanese adults. Methods: The subjects of this cross-sectional study were 635 Japanese community-dwelling people aged 69-71 years. The masticatory muscle activity required for the habitual diet was used to determine dietary hardness. Consumption of 38 foods was assessed by a validated, brief-type, self-administered diet history questionnaire. A published database was then used to estimate the masticatory muscle activity involved in the ingestion of these foods. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used for the measurement of cognitive function. Results: The principal contributors to dietary hardness were cooked rice (28.0%), green leafy vegetables (5.1%), dried fish (4.9%), and pork and beef (4.6%). There was a positive association between dietary hardness and MoCA-J score that was robust to adjustment for potential confounders (MoCA-J score per 100-unit increase in dietary hardness: β = 0.83 [95% CI: 0.08, 1.59], P = 0.03). These results did not change materially even after exclusion of subjects who reported substantial changes in their diet for any reason (β = 0.94 [95% CI: 0.02, 1.86], P = 0.04). Conclusion: This preliminary cross-sectional study suggests that dietary hardness might have a beneficial effect on cognitive function in older Japanese people. Further prospective studies with more accurate measurements are needed to confirm this finding.

Original languageEnglish
JournalJournal of Oral Rehabilitation
DOIs
Publication statusAccepted/In press - 2018 Jan 1

Fingerprint

Hardness
Cognition
Diet
Masticatory Muscles
Mastication
Cross-Sectional Studies
Independent Living
Food
Vegetables
Fishes
Eating
Databases
Prospective Studies

Keywords

  • cognitive function
  • dietary hardness
  • dietary intake
  • elderly
  • Japanese
  • masticatory muscle activity

ASJC Scopus subject areas

  • Dentistry(all)

Cite this

@article{e5ade850d4ce4ba4bc4bc6e8cd601245,
title = "Hardness of the habitual diet and its relationship with cognitive function among 70-year-old Japanese elderly: Findings from the SONIC Study",
abstract = "Background: There is increasing evidence of causal links between poor mastication and cognitive impairment, but possible effects of dietary hardness, which clearly affects mastication, on cognitive function are unknown. Objective: We investigated the hypothesis that hardness of the habitual diet would be associated with cognitive function among older Japanese adults. Methods: The subjects of this cross-sectional study were 635 Japanese community-dwelling people aged 69-71 years. The masticatory muscle activity required for the habitual diet was used to determine dietary hardness. Consumption of 38 foods was assessed by a validated, brief-type, self-administered diet history questionnaire. A published database was then used to estimate the masticatory muscle activity involved in the ingestion of these foods. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used for the measurement of cognitive function. Results: The principal contributors to dietary hardness were cooked rice (28.0{\%}), green leafy vegetables (5.1{\%}), dried fish (4.9{\%}), and pork and beef (4.6{\%}). There was a positive association between dietary hardness and MoCA-J score that was robust to adjustment for potential confounders (MoCA-J score per 100-unit increase in dietary hardness: β = 0.83 [95{\%} CI: 0.08, 1.59], P = 0.03). These results did not change materially even after exclusion of subjects who reported substantial changes in their diet for any reason (β = 0.94 [95{\%} CI: 0.02, 1.86], P = 0.04). Conclusion: This preliminary cross-sectional study suggests that dietary hardness might have a beneficial effect on cognitive function in older Japanese people. Further prospective studies with more accurate measurements are needed to confirm this finding.",
keywords = "cognitive function, dietary hardness, dietary intake, elderly, Japanese, masticatory muscle activity",
author = "{SONIC Study Group} and Hitomi Okubo and Kentaro Murakami and Hiroki Inagaki and Yasuyuki Gondo and Kazunori Ikebe and Kei Kamide and Yukie Masui and Yasumichi Arai and Tatsuro Ishizaki and Satoshi Sasaki and Takeshi Nakagawa and Mai Kabayama and Ken Sugimoto and Hiromi Rakugi and Yoshinobu Maeda and Madoka Ogawa and Ishioka, {Yoshiko Lily} and Chisato Inomatae and Taiji Ogawa and Matsuda, {Ken ichi} and Hirochika Ryuno and Ryosuke Oguro and Koichi Yamamoto and Yasushi Takeya and Yoichi Takami and Norihisa Ito",
year = "2018",
month = "1",
day = "1",
doi = "10.1111/joor.12731",
language = "English",
journal = "Journal of Oral Rehabilitation",
issn = "0305-182X",
publisher = "Wiley-Blackwell",

}

TY - JOUR

T1 - Hardness of the habitual diet and its relationship with cognitive function among 70-year-old Japanese elderly

T2 - Findings from the SONIC Study

AU - SONIC Study Group

AU - Okubo, Hitomi

AU - Murakami, Kentaro

AU - Inagaki, Hiroki

AU - Gondo, Yasuyuki

AU - Ikebe, Kazunori

AU - Kamide, Kei

AU - Masui, Yukie

AU - Arai, Yasumichi

AU - Ishizaki, Tatsuro

AU - Sasaki, Satoshi

AU - Nakagawa, Takeshi

AU - Kabayama, Mai

AU - Sugimoto, Ken

AU - Rakugi, Hiromi

AU - Maeda, Yoshinobu

AU - Ogawa, Madoka

AU - Ishioka, Yoshiko Lily

AU - Inomatae, Chisato

AU - Ogawa, Taiji

AU - Matsuda, Ken ichi

AU - Ryuno, Hirochika

AU - Oguro, Ryosuke

AU - Yamamoto, Koichi

AU - Takeya, Yasushi

AU - Takami, Yoichi

AU - Ito, Norihisa

PY - 2018/1/1

Y1 - 2018/1/1

N2 - Background: There is increasing evidence of causal links between poor mastication and cognitive impairment, but possible effects of dietary hardness, which clearly affects mastication, on cognitive function are unknown. Objective: We investigated the hypothesis that hardness of the habitual diet would be associated with cognitive function among older Japanese adults. Methods: The subjects of this cross-sectional study were 635 Japanese community-dwelling people aged 69-71 years. The masticatory muscle activity required for the habitual diet was used to determine dietary hardness. Consumption of 38 foods was assessed by a validated, brief-type, self-administered diet history questionnaire. A published database was then used to estimate the masticatory muscle activity involved in the ingestion of these foods. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used for the measurement of cognitive function. Results: The principal contributors to dietary hardness were cooked rice (28.0%), green leafy vegetables (5.1%), dried fish (4.9%), and pork and beef (4.6%). There was a positive association between dietary hardness and MoCA-J score that was robust to adjustment for potential confounders (MoCA-J score per 100-unit increase in dietary hardness: β = 0.83 [95% CI: 0.08, 1.59], P = 0.03). These results did not change materially even after exclusion of subjects who reported substantial changes in their diet for any reason (β = 0.94 [95% CI: 0.02, 1.86], P = 0.04). Conclusion: This preliminary cross-sectional study suggests that dietary hardness might have a beneficial effect on cognitive function in older Japanese people. Further prospective studies with more accurate measurements are needed to confirm this finding.

AB - Background: There is increasing evidence of causal links between poor mastication and cognitive impairment, but possible effects of dietary hardness, which clearly affects mastication, on cognitive function are unknown. Objective: We investigated the hypothesis that hardness of the habitual diet would be associated with cognitive function among older Japanese adults. Methods: The subjects of this cross-sectional study were 635 Japanese community-dwelling people aged 69-71 years. The masticatory muscle activity required for the habitual diet was used to determine dietary hardness. Consumption of 38 foods was assessed by a validated, brief-type, self-administered diet history questionnaire. A published database was then used to estimate the masticatory muscle activity involved in the ingestion of these foods. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used for the measurement of cognitive function. Results: The principal contributors to dietary hardness were cooked rice (28.0%), green leafy vegetables (5.1%), dried fish (4.9%), and pork and beef (4.6%). There was a positive association between dietary hardness and MoCA-J score that was robust to adjustment for potential confounders (MoCA-J score per 100-unit increase in dietary hardness: β = 0.83 [95% CI: 0.08, 1.59], P = 0.03). These results did not change materially even after exclusion of subjects who reported substantial changes in their diet for any reason (β = 0.94 [95% CI: 0.02, 1.86], P = 0.04). Conclusion: This preliminary cross-sectional study suggests that dietary hardness might have a beneficial effect on cognitive function in older Japanese people. Further prospective studies with more accurate measurements are needed to confirm this finding.

KW - cognitive function

KW - dietary hardness

KW - dietary intake

KW - elderly

KW - Japanese

KW - masticatory muscle activity

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U2 - 10.1111/joor.12731

DO - 10.1111/joor.12731

M3 - Article

JO - Journal of Oral Rehabilitation

JF - Journal of Oral Rehabilitation

SN - 0305-182X

ER -