Monday, October 4, 2010

Health Benefits of Vitamin D - The Sunshine Vitamin

Overview
Vitamin D is a fat-soluble vitamin that you get from the sun, thus the name, the “sunshine vitamin.” Vitamin D is mostly known for its role in helping to build strong bones. But studies show that vitamin D does much more than promote bone health.

Sources of Vitamin D
Most of the vitamin D you get comes from the sun. A mere 10 to 30 minutes of exposure to the sun at least 3 times a week can provide all the vitamin D you need, under normal circumstances.

On the other hand, if you live in areas that get little sun exposure during certain times of the year, or if you are housebound with little chance to get some sunshine, you may not be getting enough vitamin D.

Food sources of vitamin D include oily fish, fortified milk and products made from fortified milk, and fortified orange juice. Certain mushrooms that have been irradiated also contain vitamin D.

Vitamin D Synthesis
Vitamin D is made in your body when the ultraviolet B (UVB) rays of the sun hit your skin and interacts with cholesterol to form cholecalciferol. Both your liver and kidneys are involved in the conversion of cholecalciferol to the active form of vitamin D. This is the major source of vitamin D for most people.

Supplements
Vitamin D supplements are normally sold in capsules containing 500 or 1000 IUs of the vitamin. These supplements come in two forms - Vitamin D3 and vitamin D2. Vitamin D3 is made by irradiating yeast and is said to be more potent than vitamin D2. Vitamin D2, a synthetic form of the vitamin is the less potent form.

Recommended Intake
The National Academy of Sciences set 400 IUs as the recommended intake of vitamin D for adults and 200 IUs for children. On the other hand, 10 to 30 minutes of exposure to the sun, under ideal circumstances would produce about 10,000 IUs of vitamin D, which is adequate to meet the needs of most people.

Health Benefits
A number of studies show that vitamin D is important for a number of health-promoting functions that go beyond its role in bone health. Here are several health benefits that you may get from vitami D: 
  • Calcium absorption
  • Calcium transport to and from bone
  • Reduce the risk of heart disease
  • Lower blood pressure
  • Reduce the risk of stroke
  • Reduce inflammation
  • Reduce the risk of diabetes
  • Enhance the immune system
  • Fight infections
  • Reduce the risk of cancer


Vitamin D Deficiency
Vitamin D deficiency can lead to serious bone problems, including rickets in children and osteomalacia in adults. Although vitamin D deficiency low vitamin D levels have been associated with an increased risk of osteoporosis and other chronic health problems.

Summary
Get a few minutes of sun exposure daily or most days and eat dairy or other vitamin D fortified foods for added insurance. If you have low circulating levels of vitamin D, talk to your doctor and a registered dietitian to find the best course of action, which might include a vitamin D supplement.