Vitamin D is the body’s primary regulator of calcium homeostasis. It aids with bone mineralization and skeletal development. Considered a prohormone, vitamin D does not have hormone activity, but can be changed into a molecule that does.
Vitamin D helps blood cell formation, immunity, and helps cells “differentiate,” which may lower cancer risks. Vitamin D has shown in human and animal studies to possibly provide protection from autoimmune arthritis, multiple sclerosis, and juvenile diabetes.
Vitamin D helps the body maintain necessary insulin blood levels. Vitamin D receptors are located in the pancreas, where insulin is produced. Supplementation might increase the secretion of insulin in those with type 2 diabetes.
Vitamin D has been used in those with the following health problems:
The extent to which vitamin D can help reduce fractures and bone loss in the elderly is still not definite, however some evidence claims that it is useful. Vitamin C may limit or prevent perinatal growth retardation and may alleviate some forms of psoriasis. Researchers hope to find vitamin C to be beneficial to treat immunodulation, cancer, infertility, and diabetes. Early research is also showing the possibility of vitamin D being used to help seasonal depression, bilateral cochlear deafness, increase resistance to seizures, and help with multiple sclerosis and sick sinus syndrome.
- Crohn’s Disease
- Cystic Fibrosis
Vitamin D Deficiency
Vitamin D deficiency in adults may cause osteomalacia, or the softening of the bones. This condition is usually treated with calcium supplements and vitamin D. Treatment for osteomalacia should be diagnosed and treated by a physician. Abnormal bone formation occurs in those with vitamin D deficiency. The deficiency is more common in the winter when access to sunlight is restricted. Deficiencies are also more common in highly polluted areas where ultraviolet rays from the sun can be blocked.
Strict vegetarians, alcoholics, those with kidney or liver disease, and dark-skinned people are more likely suffer from vitamin D deficiency. Those with kidney or liver disease do produce vitamin D but do not activate it.
People with intestinal malabsorption more commonly are vitamin D deficient. Those with insufficient pancreatic function such as cystic fibrosis or pancreatitis, or with hyperthyroidism such as Graves’ disease, are often vitamin D deficient.
Vitamin D in supplement form can be obtained as vitamin D2 (ergocalciferol) or as vitamin D3 (cholecalciferol). Multivitamins generally contain vitamin D. Recommended dosage is 200-400 IU, or 5-10 micrograms, each day. 400 IU are found in multi-mineral, pre- and postnatal vitamins.
The elderly and those with malabsorption syndromes, hepatic failure, and nephritic syndrome receive supplements with 50,000 IU, or 1,250 micrograms, weekly for an eight week period. This should only be done under the supervision of a physician.
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