New research suggests that vitamin D does not benefit the heart health or reduce the diabetes risk of obese teens.

Researchers from Mayo Clinic Children's Center have found limited benefits from vitamin D supplements in adolescents. They also noticed that vitamin D could have the unintended consequences of increasing cholesterol and fat-storing triglycerides, HealthDay reported.

"After three months of having vitamin D boosted into the normal range with supplements, these teenagers showed no changes in body weight, body mass index, waistline, blood pressure or blood flow," Dr. Seema Kumar, a pediatric endocrinologist in the Mayo Clinic Children's Center, said in a statement. "We're not saying the links between vitamin D deficiency and chronic diseases don't exist for children -- we just haven't found any yet."

For the study, Kumar and her team looked at four clinical trials and six published studies on the topic,Medical News Today reported.

One-in-five American adolescents are obese, and more than a third are overweight, according to the Journal of American Medical Association. Several observational studies also have noted links between vitamin D deficiency and a host of weight-related medical complications, including cardiovascular diseases and insulin resistance. As a result, caregivers and providers often start high-dose supplementation in an attempt to slow or reverse some of the clinical complications associated with obesity.

"I have been surprised that we haven't found more health benefit," Dr. Kumar said. "We're not saying it's bad to take vitamin D supplements at reasonable doses, and we know most obese teens are vitamin D deficient. We're just saying the jury is still out on how useful it is for improving overall health in adolescents."

Kumar said parents and providers often put obese teens on vitamin D regimens -- sometimes at more than 5-to-10 times the recommended daily intake -- because some studies have shown a link between vitamin D in the blood and improved vascular function.  However, ingesting too much vitamin D can result in poor appetite, nausea, vomiting and kidney complications.

According to HealthDay, Kumar believes large, placebo-controlled studies are "needed to determine the long-term effects of vitamin D supplementation on children and teens."