The relationships between fat-soluble vitamin deficiency and childhood obesity risk

Objective This study aimed to examine the associations between serum levels of fat-soluble vitamins (A, D, E, and K) and obesity-related indicators in children. Methods A cross-sectional study was conducted involving 208 children stratified into an obese cohort ( n = 104) and a control group ( n = 104). Serum concentrations of vitamins A, D, E, and K were measured via liquid chromatography-tandem mass spectrometry (LC-MS), a highly sensitive and specific method for vitamin quantification. Season of blood collection was recorded and categorized as summer/autumn or winter/spring. Age-stratified analyses were conducted to explore associations between vitamin levels and obesity indices, including BMI, body fat percentage, and waist-to-height ratio. Results Vitamin D deficiency was significantly more prevalent in the obese group (62.50% vs. 28.85%, P < 0.001). Age-stratified analysis showed that vitamin D deficiency was associated with obesity in children aged 6–11 years (OR = 3.329, 95% CI: 1.618–6.854) and adolescents aged 11–17 years (OR = 4.890, 95% CI: 2.505–9.542). Conclusion Findings highlight a substantial association between fat-soluble vitamin deficiency and pediatric obesity.