<unk>  occur when the body has too little or too much<unk> . The serum level of<unk>  is closely regulated within a fairly limited range in the human body. In a healthy physiology, extracellular<unk>  levels are maintained within a tight range through the actions of parathyroid hormone, vitamin D and the<unk>  sensing receptor.<unk>  in<unk><unk>  can lead to hypocalcemia, decreased plasma levels of<unk>  or hypercalcemia, elevated plasma<unk>  levels.
Disorders of calcium metabolism
Microdamage in bone
Endocrine bone disease
Vitamin D deficiency
Steroid-induced osteoporosis
Vitamin D toxicity
Mineral deficiency
Ergogenic use of anabolic steroids