Rickets, vitamin D deficiency

Early 1900s Treatment of histamine shock, pellagra (niacin deficiency) and rickets (vitamin D deficiency) Electrocardiography and cardiac catheterization... 

Vitamin D deficiency can result in an increased excretion of calcium and phosphate and, consequently, impairs bone formation through inadequate calcification of cartilage and bones (childhood rickets). Vitamin D deficiency in adults leads to osteomalacia, a softening and weakening of bones. Hypercalcemia is a result of excessive intake of vitamin D (>50 pg/day), causing calcium carbonate and calcium phosphate deposition disorders involving various organs. 

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