A large genetic study was unable to find a link between vitamin D levels and type 2 diabetes.
The study, conducted by the University of Cambridge, challenges past evidence suggesting higher concentrations of vitamin D could help prevent type 2 diabetes, the Lancet reported.
Researchers reexamined this possible link and were not able to find a connection between gene variants that control vitamin D levels and the risk of developing type 2 diabetes. The study examined the relationship between vitamin D levels and physiological characteristics of type 2 diabetes such as "glucose and glycated haemoglobin," and were still not able to make a correlation.
"Our findings suggest that interventions to reduce the risk of type 2 diabetes by increasing concentrations of vitamin D are not currently justified. Observational studies that show a strong and consistent higher risk of type 2 diabetes with lower levels of vitamin D may do so because they have thus far not been able to adequately control for distorting or confounding factors, such as physical activity levels, that may be related both to vitamin D levels and to the risk of type 2 diabetes," Dr. Nita Forouhi, at the Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge School of Clinical Medicine said.
The recent findings do not back up a causal role of vitamin D in type 2 diabetes, but further research is needed to completely rule it out.
"[These results] need careful interpretation, and long-term randomised trials of vitamin D supplementation, which are underway, remain important. The results of a meta-analysis of 35 short-term trials, however, do not offer much hope that vitamin D supplementation can be used to prevent type 2 diabetes...The sky is becoming rather clouded for vitamin D in the context of preventing type 2 diabetes," Dr. Brian Buijsse, from the German Institute of Human Nutrition Potsdam-Rehbruecke wrote in a commentary of the study.
The findings were published Sept. 30 in the journal The Lancet Diabetes & Endocrinology.
