Evaluation of circadian rhythm and eating behavior by using salivary and urinary biomarkers

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K00895
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Eating habits
• Research Institution: Kyoto Women's University
• Principal Investigator: Komenami Naoko 京都女子大学, 家政学部, 准教授 (70291979)
• Co-Investigator(Kenkyū-buntansha): 若村 智子 京都大学, 医学研究科, 教授 (40240452)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 唾液 / コルチゾル / バイオマーカー / 非侵襲性 / 食習慣 / 生活習慣 / 高強度運動 / 朝食

Outline of Final Research Achievements

This study investigated non-invasive salivary and urinary biomarkers as useful objective indices for monitoring body conditions. Salivary cortisol secretion exhibited typical diurnal rhythm with a peak observed immediately upon awakening that then fell rapidly. Skipping breakfast affected the diurnal rhythm of salivary cortisol secretion. Food composition and moderate exercise did not affect salivary and urinary cortisol secretion. However, urinary 8-OHdG levels significantly increased after carbohydrate ingestion without exercise. In cyclists, significant positive correlations were observed between riding distance and weight loss rate as well as between riding distance and Δ cortisol secretion rate. Hypercatabolism might have been caused by high-intensity exercise that led to weight loss as well as dehydration during riding. Body conditions were successfully evaluated based on circadian rhythm, eating behavior, and exercise by using non-invasive salivary and urinary biomarkers.

Free Research Field

食生活

Academic Significance and Societal Importance of the Research Achievements

近年、24時間営業の店舗が増え、夜間の活動に伴うライフスタイルの変化や食生活の乱れ、不定愁訴などによる体調不良が指摘されることが多い。健康の維持増進やQOL(生活の質）の向上のためには、個々人の食習慣や生活スタイルを評価し、改善していくことが急務である。そのためには、質問紙による心理的・身体的コンディションの主観的評価に加えて、臨床データなどの客観的指標による評価が重要になる。そこで、非侵襲的に採取可能な唾液および尿中バイオマーカーであるコルチゾルなどを分析することにより、生体リズムおよび食習慣を含む生活スタイルの評価を行って、栄養指導や生活指導に役立つエビデンスを収集することは意義がある。