Vitamin D may lower diabetes risk in the obese

A new US study suggests that regular high-dose vitamin D supplementation may help obese children and adolescents to control their blood sugar levels, potentially reducing their risk of developing diabetes.

The randomized controlled trial included 35 pre-diabetic obese children and adolescents who were undergo-ing treatment as part of a diabetic obesity program (1). The participants, who all had insufficient or deficient vitamin D levels and similar diets and activity levels, received either a high-dose vitamin D3 supplement (4000 IU) or a placebo daily for six months. The study results showed that the children and teenagers who had taken the supplement had sufficient blood vitamin D concentrations at the end of the study and had significantly lowered the amount of insulin in their blood, despite no changes in body weight or physical activity.

The researchers concluded that adding vitamin D supplements to the diets of obese patients may be an effective complement to the treatment of obesity and its associated insulin resistance. Vitamin D supple-mentation could be a natural, inexpensive way to decrease diabetes risk and avoid the side effects that might come from taking drugs to control blood sugar. Clinicians should therefore check the vitamin D status of their obese patients, because they are likely to have insufficient blood concentrations. It is thought that obese individuals process vitamin D about half as efficiently as people of a healthy weight, as the vitamin gets stored in their fat tissues, which keeps it from being metabolized. This means obese individuals need to take in about twice as much vitamin D as their leaner peers to maintain sufficient levels of vitamin D, the scientists added.

1. Belenchia A. M. et al. Correcting vitamin D insufficiency improves insulin sensitivity in obese adolescents: a randomized controlled trial. American Journal of Clinical Nutrition. Published online March 2013.