TUESDAY, Dec. 6 (HealthDay News) -- Low levels of vitamin D are much more common in obese children than in those who aren't obese and are associated with insulin resistance, a risk factor for type 2 diabetes, researchers have found.

The study included 411 obese children and 87 children who weren't overweight. Researchers measured the children's vitamin D levels, blood sugar levels, serum insulin, body mass index and blood pressure.

The children were also asked about their daily consumption of soda, juice, milk, fruits and vegetables, and whether or not they routinely skipped breakfast.

The findings are slated for publication in the January issue of the Journal of Clinical Endocrinology & Metabolism.

"Our study found that obese children with lower vitamin D levels had higher degrees of insulin resistance," lead author Dr. Micah Olson, of the University of Texas Southwestern Medical Center in Dallas, said in a news release from the Endocrine Society. "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."

Obese kids who had poor dietary habits, such as skipping breakfast and drinking lots of soda and juice, also tended to have lower vitamin D levels, the study found.

Future research should look at whether making sure obese kids get adequate vitamin D could also help with insulin resistance, Olson added.

Past studies have linked low vitamin D levels with cardiovascular disease and type 2 diabetes. It's not fully known how obesity and associated conditions are related to vitamin D deficiency.

More information

The U.S. Centers for Disease Control and Prevention has more about childhood overweight and obesity.