An excess of vitamin D causes abnormally high blood concentrations of calcium, which can cause overcalcification of the bones, soft tissues, heart and kidneys. In addition, hypertension can result. Symptoms of<unk>  may include the following: * Dehydration * Vomiting * Diarrhea * Decreased appetite * Irritability * Constipation * Fatigue * Muscle weakness *Metastatic calcification of the soft tissues Symptoms of<unk>  appear several months after excessive doses of vitamin D are administered. In almost every case, a low-calcium diet combined with corticosteroid drugs will allow for a full recovery within a month. It is possible that some of the symptoms of<unk>  are actually due to vitamin K depletion. One animal experiment has demonstrated that co-consumption with vitamin K reduced adverse effects, but this has not been tested in humans. However the interconnected relationships between vitamin A, vitamin D, and vitamin K, outlined in a 2007 paper published in the journal Medical Hypotheses, describes potential feedback loops between these three vitamins that could be elucidated by future research. A mutation of the CYP24A1 gene can lead to a reduction in the degradation of vitamin D and to hypercalcaemia (see Vitamin_D: Excess).
Vitamin D toxicity
Vitamin D deficiency
Steroid-induced osteoporosis
Secondary hyperparathyroidism
Tertiary hyperparathyroidism
Oncogenic osteomalacia
Metabolic bone disease
Skeletal fluorosis