Effect of Vitamin D Supplementation on Inflammation and Cardiometabolic Risk Factors in Obese Adolescents

The Effect of Vitamin D on Cytokines and Cardiometabolic Risk in Obese Adolescents

Large studies of children show that over half of the children in the United States of America do not have enough vitamin D stored in their bodies. In children who are overweight or obese, the percentage of children who do not have enough vitamin D is even higher.

Vitamin D is essential for the body to maintain normal calcium levels and strong bones. Recent research shows that through the actions of inflammatory markers, levels in the blood that measure inflammation in the body, vitamin D plays many other important roles in the body like helping to regulate the immune system, blood sugar levels, blood pressure, and body fat.

The purpose of this study is to determine the effect of vitamin D supplementation on inflammatory markers in obese and overweight adolescents. As a secondary goal, we would like to evaluate cardiometabolic risk factors and the correlation between body mass index, vitamin D stores and inflammatory cytokines.

In an observed, randomized controlled trial over 6 months we will provide observed vitamin D supplementation or placebo to healthy obese and overweight adolescents and measure changes in inflammatory markers, lipids, blood pressure, and mean blood sugars. We hypothesize that administration of vitamin D to these patients will improve their inflammatory profile and cardiometabolic risk factors (blood glucose, blood pressure, and lipid profile).

Supplementation with vitamin D at 150,000 IU every 3 months failed to increase serum 25-hydroxy vitamin D (25OHD) or alter inflammatory markers and lipids in overweight and obese youth. Further studies are needed to establish the dose of vitamin D required to increase 25OHD and determine potential effects on metabolic risk factors in obese teens.

During the course of the study, blood pressure removed from the prespecified outcome measures.

Inclusion Criteria:

1. Ages 11 years to 17.99 years old
2. BMI: 85 percentile for age and gender

Exclusion Criteria:

1. Patients who currently receive:

   • vitamin D supplementation >= 400 IU/day
   • daily glucocorticoids or anti-epileptics

2. Patients who currently have or history of:

   • 25-OH vitamin D level < 10 ng/ml or > 60 ng/ml
   • rickets
   • diabetes mellitus
   • liver or kidney disease
   • malabsorptive disorders
   • genetic syndromes associated with obesity (i.e. Prader-Willi)
   • lactose deficiency or insufficiency
   • galactosemia