VITAMIN D EXCESS

also called Hypervitaminosis D, toxic symptoms resulting from a prolonged high intake of vitamin D, a fat-soluble nutrient. Unlike the water-soluble vitamins, a surplus of vitamin D in the body is not eliminated in the urine but remains in the body, sometimes reaching toxic levels. A vitamin D-poisoned individual may complain of weakness, fatigue, loss of appetite, nausea, and vomiting. Examination may reveal small yellowish deposits beneath the fingernails, in the eyes, and scattered over the skin. In infants and children there may be growth failure. Because vitamin D is involved in the intestinal absorption of calcium, this mineral may reach abnormally high concentration in the blood (hypercalcemia), and autopsies have revealed widespread deposition of calcium phosphate throughout the body, particularly in the kidneys. Toxic manifestations have been observed in adults receiving 50,000 to 100,000 International Units daily and in infants on relatively low daily intakes of 2,000 to 4,000 International Units.