Review: Vitamin D3 deficiency results in dysfunctions of immunity with severe fatigue and depression in a variety of diseases.
Höck, Anna Dorothea·In vivo (Athens, Greece)·2014
This review explains how vitamin D3 deficiency may contribute to severe fatigue and depression in conditions like ME/CFS. Vitamin D3 helps regulate the immune system, and without enough of it, the body's natural defenses become unbalanced, allowing infections and inflammation to persist. The authors suggest that vitamin D3 supplements might help prevent or improve these chronic conditions.