Obese kids had lower vitamin D levels U.S. researchers found compared to normal weight children, obese children have lower vitamin D levels. DALLAS, March 20 (UPI) -- U.S. researchers found compared to normal weight children, obese children have lower vitamin D levels. Dr. Michele Hutchison is at the University of Texas Southwestern Medical Center at Dallas U.S. teenagers had lower vitamin D levels than younger children, partly because they often skipped breakfast and drank more soda. "Those children with the lowest levels of vitamin D in their blood were also the children that seemed to be at the highest risk of having prediabetes, as measured by a marker for insulin resistance," Hutchison said in a statement. Prediabetes is a condition in which someone is thought to be at high risk for developing type 2 diabetes -- most often associated with older age, obesity, family history of diabetes, previous history of gestational diabetes, physical inactivity, and certain ethnicities. About 80 percent of people with type 2 diabetes are overweight. Type 2 diabetes is increasingly being diagnosed in children and adolescents, especially among African-American, Mexican-American, and Pacific-Islander youth. When type 2 diabetes is diagnosed, the pancreas is usually producing enough insulin, but for unknown reasons the body cannot use the insulin effectively, a condition called insulin resistance. After several years, insulin production decreases. The result is the same as for type 1 diabetes -- glucose builds up in the blood and the body cannot make efficient cient use of its main source of fuel. The study in the Journal of Clinical Endocrinology and Metabolism.