Vitamin D serves multiple important functions in the immune system.
Why Does Vitamin D Deficiency Exist?
The reasons for widespread vitamin D deficiencies in various populations are not completely understood.
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Diet may be another explanation for the deficiency.
Aranow C.Vitamin D and the immune system.J Investig Med.
2014;144:138145. doi:10.1016/j.jsbmb.2013.11.003
Stokes CS, Lammert F.Vitamin D supplementation: less controversy, more guidance needed.F1000Res.
2016;5:2017. doi:10.12688/f1000research.8863.1
National Institutes of Health.
Office of Dietary Supplements.Vitamin D fact sheet for health professionals.
