1. Objectives The aim of this study was to examine the relationship between dietary habits and 25(OH)D status in obese children. Examine the relationship between 25(OH)D and glucose homeostasis. Cross-sectional observational study

2. Selection of Subjects 411 obese children (BMI >95 th percentile for age group) ages 6-16  Recruited from Center of Obesity and its Consequences on Health in Dallas, Texas 89 non overweight children  Recruited from Endocrinology Center after being treated for hypothyroidism or GH deficiency, but otherwise healthy Exclusion criteria: use of anticonvulsant, vitamin D supplement more than 400 IU/day, other relevant disorders

3. Data collected Age, sex, ethnicity, height, weight, blood pressure, dietary habits Laboratory data  Serum 25(OH)D  HbgA1C  Fasting glucose and insulin  OGTT  HOMA-IR

4. Statistical Analysis Prevalence of Vit D insufficiency determined for obese and non-overweight populations within each ethnic group and season  Data collected in summer, fall, winter, spring  Sufficiency: 75 nmol/L  Insufficiency: < 75 nmol/L  Deficiency: < 50 nmol/L  χ squared to determine prevalence rate

5. Statistical Analysis cont. Two way ANOVA to compare 25(OH)D between groups and assess interaction btw obesity and season; gender and ethnicity Pearson coefficients used to determine relationship btw 25(OH)D and:  2h glucose  HbbA1c  HOMA-IR  Blood pressure