Association between body mass index and body fat in 9-11-year-old children from countries spanning a range of human...

Area of Science:

• Pediatric Endocrinology
• Global Health
• Anthropometry

Background:

• Childhood obesity is a growing global concern.
• Understanding the relationship between Body Mass Index (BMI) and body fat is crucial for public health.
• Cross-cultural variations in body composition need further investigation.

Purpose of the Study:

• To assess the association between Body Mass Index (BMI) and body fat.
• To examine these associations in a multinational sample of children aged 9-11 years.
• To explore potential country-specific differences in body composition relative to BMI.

Main Methods:

• Utilized data from 7265 children across countries with varying human development levels.
• Measured total body fat (TBF) and percentage body fat (PBF) using a Tanita SC-240 scale.
• Calculated BMI z-scores (BMIz) using WHO and CDC reference data; employed multilevel models to estimate mean PBF at different BMIz levels.

Main Results:

• Consistently high correlations (>0.90) between BMI and TBF observed across all countries.
• Correlations between BMI and PBF ranged from 0.76 to 0.96.
• Identified specific country-based variations: Indian boys showed higher PBF, Kenyan girls lower PBF, and Colombian children exhibited higher PBF at various BMIz levels compared to others.

Conclusions:

• Body Mass Index (BMI) is a reliable indicator of adiposity in children across diverse global settings.
• Significant cross-cultural differences exist in body fat percentage even at similar BMIz levels.
• Further research is needed to understand the determinants of these observed variations in childhood body composition.