Exploring the Relationship between Chronotype and Waist Circumference: A Scoping Review.

Area of Science:

• Chronobiology
• Metabolic Health
• Public Health

Background:

• Chronotype, an individual's daily biological rhythm, influences metabolic health.
• Waist circumference (WC) is a recognized indicator of central obesity and metabolic risk.
• Understanding the link between chronotype and WC is crucial for personalized health strategies.

Purpose of the Study:

• To systematically review existing literature on the relationship between chronotype and waist circumference.
• To identify knowledge gaps and suggest future research directions in this area.
• To explore the implications for metabolic health management.

Main Methods:

• A comprehensive literature search was conducted across Scopus, Web of Science, and PubMed.
• The review followed the PRISMA extension for scoping reviews.
• Thirty-three relevant articles were included in the final analysis.

Main Results:

• A majority of studies (88%) found a significant positive correlation between evening chronotype and higher WC.
• Individuals with an evening chronotype generally exhibited larger mean WC compared to morning chronotype individuals.
• The significance of this difference varied across studies, highlighting potential inconsistencies.

Conclusions:

• Higher waist circumference values are associated with eveningness, indicating a potential link to metabolic health risks.
• Standardized definitions for chronotype categorization may be necessary for global applicability.
• Further validation using objective chronotype assessment methods is warranted.