Vitamin D toxicity (Hypervitaminosis D).
As it has already been mentioned in another page, vitamin D is fat-soluble  and can be stored in fat cells. In excessive and prolonged uptake the vitamin accumulates within the body and can cause hypervitaminosis D, a condition that is characterized by toxicity symptoms. Sun exposure does not seem to be able to result in vitamin D toxicity, since the body is able to control the production of the vitamin. Some of the signs of overdose may appear several months after the toxic levels are reached.
Excessive amounts
of vitamin D leads to abnormally high concentrations of calcium in the bloodstream. In turn, excessive amounts of calcium can cause serious damage to the heart, lungs, muscles and other soft tissues by saturating them. Hypervitaminosis D may lead to renal disorders and kidney stones because of the high calcium concentrations in blood and urine. Although in normal levels vitamin D promotes good bone formation and improves bone density, in toxicity state, it can result in loss of bone.
Symptoms of hypervitaminosis D include dehydration, nausea, vomiting, decreased appetite, unintentional weight loss, skin rash, constipation, excessive thirst, increased urination, high blood pressure, fatigue, weakness, headaches, irritability and confusion.
The tolerable upper intake level (UL) for vitamin D is 25mcg/day or 1,000 IU/day for infants and 50mcg/day or 2,000 IU/day for children and adults, although pregnant women are advised not to exceed the 800 IU per day.
If the condition is diagnosed at early stages, symptoms can retreat easily, as soon as the vitamin uptake is discontinued. In more serious cases, certain treatments may be required, depending on the damage inflicted on organs or tissues. |
