Vitamin D deficiency has been linked to a number of different medical conditions and is known to cause bone problems such as rickets. Its main source is sunlight but it can also be found in fish, eggs, dairy products and fortified margarines and cereals. Researchers at St Bernard's Hospital, Middlesex looked at vitamin D levels in 17 male psychiatric inpatients. They found that 15 of them had vitamin D deficiency while the other two had borderline deficiency. The vitamin levels of the inpatients could be restored with the use of calcium and ergocalciferol tablets but the authors of the study recommended that all psychiatric inpatients should have adequate exposure to sunlight and healthy diets to ensure that they receive their recommended daily amounts of vitamins and minerals.
Tiangga, Eleanor, Gowda, Asha and Dent, John A. - Vitamin D deficiency in psychiatric in-patients and treatment with daily supplements of calcium and ergocalciferol Psychiatric Bulletin 2008, 32: 390-393