Background:

Low levels of vitamin D have been associated with a range of clinical conditions such as obesity, insulin resistance, and diabetes mellitus, among others. There are few studies that measure the active form of vitamin D (1,25 (OH)2 vitamin D) in obese children. However, published data are inconclusive. The aim of this study was to determine the active levels of vitamin D in obese and overweight children and to find an association between low levels of vitamin D, obesity and impaired glucose metabolism.

Methods:

A cross-sectional, analytical study was conducted in 6 to 12-year-old children with excess adiposity determined by waist-stature index and body mass index. Levels of glucose, insulin, complete lipid profile, homeostatic model assessment and the active form of vitamin D were measured in each patient. Levels < 30 pg/ml were considered as low levels of vitamin D.

Results:

The prevalence of low levels of active vitamin D was 36%. A significant association between low levels of active vitamin D and high levels of insulin was found. No significant association was found between vitamin levels and adiposity measures.

Conclusions:

Low levels of active vitamin D were found in 36% of the population studied. A significant association with insulin resistance and hyperinsulinemia was demonstrated.