Summary: Diabetes with its increasing incidence is considered to be a global epidemic. The same lifestyle changes that contribute to development of diabetes may also cause other health problems. One of them is vitamin D deficiency whose prevalence is also increasing. Naturally, a question about association between the two occurs. We have tried to find the answers for questions considering vitamin D that appear frequently in daily practice of general practitioners and diabetologists: can vitamin D deficiency lead to diabetes or play a role in glycemic control? Should we routinely test the level of vitamin D in diabetic patients? Can vitamin D supplementation be considered a part of prevention or treatment of diabetes?
This review shows physiological mechanisms in which vitamin D may influence carbohydrate metabolism. We briefly discussed the most important clinical trials considering vitamin D and prediabetes, diabetes type 1 and 2 and their complications. We also reviewed internationally recognized recommendations on the subject.
Despite the fact that different aspects of association between vitamin D and diabetes are the subject of interest for scientists for over twenty years, there are still not so many studies that are designed with good enough methodology to draw firm conclusions. That is why, according to guidelines of Diabetes Poland, we recommend the same supplementation of vitamin D for diabetic patients as for general population. We need to stress the asscociation between vitamin D and beta cell function: the impact of hypovitaminosis on decreased insulin release and increase of insulin resistance.