Type 1 Diabetes: Vitamin D Deficiency Occurs in an Early Stage

28 Feb 2014 --- Low levels of vitamin D are commonly found in people with type 1 diabetes. But even children who have multiple positive islet autoantibodies without manifest type 1 diabetes have lower levels of vitamin D in their blood. This does not appear, however, to influence the progression of the disease from pre-diabetes to diabetes, according to scientists from the Helmholtz Zentrum München and the Technical University of Munich in the specialist journal Diabetologia.

Vitamin D is known as a major regulator of calcium levels and bone metabolism. Furthermore, it also influences the immune system. Previous studies have shown that patients with recently diagnosed type 1 diabetes have significantly lower vitamin D levels.

Scientists from the Institute of Diabetes Research (IDF) and the Helmholtz Zentrum München, a member of the German Center for Diabetes Research (DZD), as well as from the Diabetes Research Group at the Technische Universität München (TUM) examined whether a vitamin D deficiency occurs during an early stage of type 1 diabetes, defined by the presence of multiple diabetes-specific islet autoantibodies. Furthermore they also determined whether vitamin D deficiency influences the progression to type 1 diabetes in children with multiple islet autoantibodies.

Children who had not yet developed clinical type 1 diabetes but who have multiple positive autoantibodies in their blood were found to have lower vitamin D levels than children without diabetes-specific autoantibodies. Interestingly, the differences in vitamin D levels were most prevalent in the summer months. These results were obtained from the BABYDIET, BABYDIAB, TEENDIAB and DIMELLI* diabetes studies. The team of scientists headed by Jennifer Raab, Dr. Christiane Winkler and Professor Anette-Gabriele Ziegler compared the vitamin D measurements taken from 108 children who were tested positive for islet autoantibodies with 406 children without autoantibodies. Lower vitamin D levels were also found in 244 children who had recently been diagnosed with type 1 diabetes.

Prediabetes is defined as the presence of multiple islet autoantibodies. If and when the disease progresses, however, does not seem to be influenced by the vitamin D levels. Within the group of children with positive autoantibodies, a few children quickly developed type 1 diabetes – however this was independent from their vitamin D levels.

“Vitamin D deficiency precedes the onset of type 1 diabetes. This may be a consequence of an immune response,” Professor Ziegler says. “In the case of prediabetic children, we must therefore be mindful of the risk of vitamin D deficiency and consider recommending vitamin D supplementation at an early stage of type 1 diabetes.”

Reference: Raab, J. et al. (2014): Prevalence of vitamin D deficiency in pre-type 1 diabetes and its association with disease progression, Diabetologia, doi: 10.1007/s00125-014-3181-4