The Effect of Yogurt Consumption on Body Fat Percentage in School-Age Children: A Quantile Regression Analysis.

Yogurt consumption was inversely associated with body fat percentage in boys across multiple quantiles of BFP distribution.

• Quantile regression showed significant correlations at the 0.25, 0.50, 0.75, 0.85, and 0.95 quartiles for boys after adjusting for potential confounders.
• Regression coefficients for boys were -0.207 (0.25 quartile), -0.300 (0.50 quartile), -0.688 (0.75 quartile), -0.570 (0.85 quartile), and -0.465 (0.95 quartile).
• The largest inverse association in boys was observed at the 0.75 quantile (coefficient -0.688), suggesting stronger effects among boys with higher body fat.
• Daily yogurt consumption was adjusted using the density method (daily yogurt consumption × 1000/total energy consumption) to account for total energy intake.

Yogurt consumption was inversely associated with body fat percentage in girls, but only at higher quantiles of the BFP distribution.

• Significant correlations were found only at the 0.75 and 0.85 quartiles for girls after adjusting for confounders.
• Regression coefficients for girls were -0.290 (0.75 quartile) and -0.582 (0.85 quartile).
• The association in girls was limited to higher body fat quantiles, indicating a sex difference in the yogurt-BFP relationship.
• Girls aged 15-17 years had the highest median BFP of 31, compared to 17.5 for boys in the same age group.

Body fat percentage and yogurt consumption differed substantially between boys and girls across age groups.

• Boys aged 6-10, 11-14, and 15-17 years had median BFP values of 19.6, 19.5, and 17.5, respectively.
• Girls in the same age groups had median BFP values of 20.3, 26.4, and 31.0, respectively, showing a marked increase with age unlike boys.
• Boys aged 6-10 and 11-14 years had median daily yogurt consumptions of 28.6 g/day, declining to 21.4 g/day at ages 15-17.
• Girls maintained relatively stable yogurt consumption across age groups: 28.6 g, 29.6 g, and 28.6 g/day for the three age groups.

The study used a large, nationwide, multi-stage stratified random sample of Chinese children aged 6-17 years.

• The sample included 48,305 children aged 6-17 years.
• Body fat percentage was measured using bioelectrical impedance analysis (BIA).
• Covariates adjusted for included age, pubertal development stage, geographical region, total daily energy consumption, physical activity duration, annual household income, parental educational attainment, and consumption of other food categories.
• Quantile regression was the primary statistical method used to analyze the association between yogurt consumption and BFP.

The inverse association between yogurt and body fat was stronger at higher quantiles of body fat distribution compared to lower quantiles.

• In boys, the regression coefficient at the 0.75 quantile (-0.688) was more than three times larger in magnitude than at the 0.25 quantile (-0.207).
• The pattern suggests that children with higher body fat may experience a greater benefit from yogurt consumption.
• This heterogeneity in association across quantiles was a key reason for employing quantile regression rather than standard mean regression.
• For girls, no significant associations were detected at the 0.25 and 0.50 quantiles, with significant effects only emerging at the 0.75 and 0.85 quantiles.