Vitamin D is one of the four fat soluble vitamins and one vitamin that can be obtained through exposure to the sun. Vitamin D is also nick named the sunshine vitamin for obvious reasons. There are 5 forms of vitamin D, but only two are physiologically relevant to us. Forms D2 (ergocalciferol) and D3(cholecalciferol) are the two we use, and D3 is produced from our skin. Vitamin D is carried in the blood to the liver where it is then converted to calcidiol, which can then be converted in the kidneys to the biologically active form of vitamin D called calcitriol. Vitamin D inefficiency is most popularly linked to osteoporosis and rickets.

Vitamin D and Bone Strengths:
Vitamin D plays a major role in building and maintaining strong bones. Vitamin D increases bone strength by increasing the calcium that is absorbed through your intestines, increasing osteoclast (bone building) numbers, maintaining phosphate and calcium levels, and helping the parathyroid hormone to maintain calcium levels. Those that are deficient in vitamin D are at a high risk for lower bone density, osteoporosis, and therefore are at a higher risk for bone fractures.

Immune System and Vitamin D:
A study done at University of Copenhagen has come to the conclusion that vitamin D aids T cells in our bodies. Without vitamin D these cells will not be able to react to a foreign substance and won’t be able to protect us. If someone is lacking vitamin D their T cells will not be activated to attack a virus or bacteria. If the T cells just lay dormant, than you will have no line of defense to ward off an illness. Professor Carsten Geisler from the Department of International Health, Immunology and Microbiology, was quoted: “When a T cell is exposed to a foreign pathogen, it extends a signaling device or ‘antenna’ known as a vitamin D receptor, with which it searches for vitamin D. This means that the T cell must have vitamin D or activation of the cell will cease. If the T cells cannot find enough vitamin D in the blood, they won’t even begin to mobilize. ” Be sure to be getting your vitamin D BEFORE you get ill.

Multiple Sclerosis and Vitamin D:
Multiple Sclerosis or MS is a disease that results from the body’s failure to recognize itself. The immune system will then attack and destroy the sheath that protects nerves. The body cannot distinguish between itself and a foreign substance or infection. This turns the body’s normally effective defense system against itself. Since vitamin D is an immune system regulator people who spend more time outside have less occurrence of MS. People living in regions where they can spend time outside year round have a much less potential to get MS. Vitamin D pills are now being used as a treatment for MS

Vitamin D and Asthma Control:
According to a study, published in the American Journal of Respiratory and Critical Care Medicine, done with 600 Costa Rican children serum vitamin D levels were linked to asthma severity. The study found that children who lad lower serum vitamin D levels were more likely to have been hospitalized from asthma, and use more inhaled medicine. There still needs to be more research on this topic as the study was a simple epidemiological study.

Other Benefits:
Vitamin D has been casually linked to other benefits such as healthy brain aging, helping maintain a healthy body weight, protection against low levels of radiation, and some studies have shown that people with appropriate levels of vitamin D are at lower risk to develop cancer.

Foods with Vitamin D:
If you are not getting enough vitamin D by simply being outside there are foods that you can get vitamin D from. Many foods are now fortified with vitamin D like milk which was fortified to help prevent rickets in the 1930s. Here is a list of foods with vitamin D:

Vitamin D Requirements:
Birth to 12 months – 400 IU
1-13 years – 600 IU
14-18 years – 600 IU
19-70 years – 600 IU
71+ years – 800 IU
Pregnant/Breastfeeding women – 600IU

Vitamin D Supplements:
If you are usually active during the summer months it may be a wise idea to start supplementing vitamin D during the winter when you’re not getting vitamin D naturally from the sun. You do not need to get your whole daily requirements from supplements, but you can help reach that value with foods high in vitamin D and supplements. The best plan of attack for obtaining enough vitamin D is to balance your foods with vitamin D and your supplement usage. Vitamin D supplements happen to be fairly cheap, so it’s not a huge investment for some incredible health benefits. Here are some examples of cheap effective vitamin D supplements!