The findings of a large, multi-national study which began in 2004 have linked high levels of vitamin D in childhood with a reduced risk of diabetes. Published in November’s print edition of the journal Diabetes, the report looked at children enrolled in The Environmental Determinants of Diabetes in the Young (TEDDY) study.
The research was led by primary author Dr Jill Norris, MPH, PhD, of the Colorado School of Public Health, University of Colorado, and focused on islet autoimmunity; the precursor to type 1 diabetes. “For several years there has been controversy among scientists about whether vitamin D lowers the risk of developing islet autoimmunity and type 1 diabetes,” says Norris. Islet autoimmunity – when the immune system attacks the islet cells within the pancreas, thus inhibiting insulin production and causing type 1 diabetes – was the key focus of the study.
For this large-scale study, researchers recruited and analyzed 8,676 children from Sweden, Finland, Germany and America, each of whom had an increased genetic risk of diabetes. Children aged between three months and 48 months visited the clinics every three months, after which time the visits reduced to bi-annual.
Comparisons were drawn between 376 children who had developed islet autoimmunity and 1,041 children who had not. The data from blood sample analysis showed that in the cases where vitamin D levels were lower in infancy and childhood, islet autoimmunity later in life was more prevalent, which gives a clearer picture into vitamin D’s efficacy in diabetes prevention.
Whether supplementation of vitamin D can assist in diabetes prevention remains to be proven. Norris comments: “High levels of plasma 25-hydroxyvitamin D was associated with a reduced risk of islet autoimmunity and type 1 diabetes. We look to future prospective studies to confirm whether a vitamin D intervention can help prevent type 1 diabetes.”