Seasonal variability in body mass index, waist circumference, and skinfolds in Norwegian children

Am J Hum Biol. 2024 Sep;36(9):e24084. doi: 10.1002/ajhb.24084. Epub 2024 Apr 12.

Abstract

Objectives: Studies have shown that children develop a higher body weight during summer months. This has been demonstrated repeatedly using the body mass index (BMI), but the effect of season on other weight-related anthropometric measurements is still unclear.

Methods: Measurements of height, weight, waist circumference (WC), triceps, and subscapular skinfolds (TSF and SSF), collected from September till May in a cross-sectional sample of 4-16-year-old children and adolescents (n = 4525) from the Bergen Growth Study 1 (BGS1). Differences in z-score by season were tested with linear models adjusted for age group and separately for sex. Overall differences were tested with a one-way between-group analysis of variance.

Results: The girls had higher BMIz (+0.12, p = .03) and WCz (+0.18, p = .002) in fall compared with spring. TSFz (-0.19, p < .001) and SSFz (-0.18, p < .001) were lower in winter in girls, and in boys both in fall (TSFz -0.10, p = .046; SSFz - 0.16, p < .001), and winter (TSFz -0.15, p = .004; SSFz -0.14, p = .003), when compared with spring.

Conclusions: Seasonal variation was detected for all anthropometric measures, but differences in the direction of the effect between measures of global (BMI), central (WC) or subcutaneous (SF) adiposity suggest a more complex mechanism that needs further exploration.

MeSH terms

  • Adolescent
  • Body Mass Index*
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Female
  • Humans
  • Male
  • Norway
  • Seasons*
  • Skinfold Thickness*
  • Waist Circumference*