Association between Calcium, Magnesium and Lipid Levels of Vitamin D Deficiency in Obese Children: A Cross-sectional Descriptive Study

Vitamin D deficiency is a widespread health issue among obese children, contributing to metabolic disturbances despite adequate sunlight exposure in many regions. Understanding its relationship with biochemical markers is crucial for early detection and intervention. This study aimed to evaluate the association between serum vitamin D levels and calcium, magnesium, cholesterol, and triglycerides in morbidly obese children. It sought to identify potential early biomarkers of metabolic dysfunction related to hypovitaminosis D. The study was conducted at the Women’s and Children’s Hospital in Diwaniyah, Iraq, from March to July 2025. Blood samples were collected from 50 children (28 females and 22 males) aged 6–16 years (mean age: 11.2 ± 2.9 years, median: 11 years), diagnosed with morbid obesity. Participants were prepubescent to early pubescent, determined by clinical records. Anthropometric measurements were recorded using standardized equipment. Biochemical analysis included spectrophotometric enzyme assays for calcium, magnesium, cholesterol, and triglycerides, and CLIA for 25(OH)D. Data were analyzed using SPSS v26.0 with Pearson’s correlation and linear regression tests. Results showed that 86% (n = 43) of participants had vitamin D deficiency (< 20 ng/mL), with a mean level of 15.2 ± 3.5 ng/mL. Elevated cholesterol was observed in 64% (n = 32) and high triglyceride levels in 70% (n = 35). Mean calcium was 8.7 ± 0.4 mg/dL and magnesium 1.8 ± 0.2 mg/dL, with low magnesium in 36% (n = 18). A moderate negative correlation was found between vitamin D and triglycerides (r = -0.45) and cholesterol (r = -0.41), while positive correlations were observed with magnesium (r = 0.35) and calcium (r = 0.28). The findings indicate that vitamin D deficiency in morbidly obese children is significantly associated with lipid abnormalities and marginal mineral status, suggesting its potential role as a biomarker of early metabolic risk.