Leader author Dr. Micah Olson of The University of Texas Southwestern Medical Center in Dallas said high rates of vitamin D deficiency have been found in obese populations, and past studies have linked low vitamin D levels to cardiovascular disease and type 2 diabetes -- but why this occurs is not fully known.
Olson and colleagues measured vitamin D levels, blood sugar levels, serum insulin, body mass index and blood pressure in 411 obese subjects and 87 control non-overweight subjects.
Study participants were asked to provide dietary information including daily intake of soda, juice and milk, average daily fruit and vegetable intake, and whether they routinely skipped breakfast, Olson said.
"Our study found that obese children with lower vitamin D levels had higher degrees of insulin resistance," Olson said in a statement. "Although our study cannot prove causation, it does suggest that low vitamin D levels may play a role in the development of type 2 diabetes."
The study, published in the Journal of Clinical Endocrinology & Metabolism, found poor dietary habits such as skipping breakfast and increased soda and juice consumption were associated with lower vitamin D levels in obese children.