Vitamin D Essentials
A Very Important Vitamin That Many Are Deficient In
Vitamin D is not technically a vitamin. Vitamins are classified as organic chemical compounds that cannot be synthesized sufficiently by the body and must be acquired from the diet. However, vitamin D can be synthesized from cholesterol in sufficient amounts with adequate exposure to sunlight. It is estimated that ten to fifteen minutes in direct sunlight a day is a sufficient amount of time to synthesize the required amounts of vitamin D.
Sources of Vitamin D
Vitamin D can be ingested as cholecalciferol (vitamin D3), which is attained from animals and supplements, or ergocalciferol (vitamin D2), which is attained from plant life and supplements. Research indicates that the ingested D3 form is better, because it takes much more D2 to be as effective because D3 stays active longer in the body so more D2 is needed to be as effective. Evidence supports that vitamin D syntesized from the sun appears to be the best way to get vitamin D because sun exposure works in a feedback loop that prevents toxicity. There are concerns about taking vitamin D supplements in excess because it can cause toxicity, but there isn't that concern with getting vitamin D from the sun. The concern with getting vitamin D from the sun is getting cancer from too much sun exposure, because with the depletion of the ozone layer minimizes the protection we get from it and more ultraviolet radiation is allowed to reach the earth which leads to increase rates of cancer.
Vitamin D In the Body
The liver converts these sources of vitamin D into calcidiol, which is also known as 25-hydroxycholecalciferol, or 25-hydroxyvitamin D, and is abbreviated 25(OH)D). This 25(OH)D) is the specific vitamin D that is measured in serum to determine a person's vitamin D level. The kidneys convert part of the calcidiol into calcitriol, which is the biologically active form of vitamin D. Calcitriol circulates as a hormone in the blood, and regulates the amount of calcium and phosphate in the bloodstream, to promote the healthy growth and repair of bones. Calcitriol also affects neuromuscular function and inflammation. Calcidiol is also converted to calcitriol outside of the kidneys for purposes such as the growing of new cells and destruction old of cells.
Amount Of Needed 25(OH) Vitamin D
Newer Studies show that the optimal level of 25(OH)D in the blood should be between 50-70 ng/ml. The old standard was a minimum of 30 ng/ml. Many people who live in the cities are vitamin deficient because they don't get enough exposure to the sun and they don't meet the old standard of 30 ng/ml. The number of vitamin D deficient people would sky rocket if the 50-70 ng/ml scale is used. Some people feel that 70 should be the minimum ng/ml level, and anything greater than 100 ng/ml is excessive or toxic. I recently had my vitamin D levels tested and the acceptable range was still 30-100 ng/ml. My blood results showed that my vegan diet provided me with all the nutrients I needed in the optimal range, except for vitamin D. I was deficient in vitamin D before I started on my vegan diet, and my vitamin D levels dropped after I became vegan. Vegans and vegetarians need to watch their vitamin B12 and D levels because these diets often lack these two vitamins. My vitamin B12 were fine. I now take vitamin D supplements, which is the only vitamin supplement I take, and I try to get out in the sun a little bit more.
Vitamin D's Affect On The Body.
Vitamin D was primarily regarded as an important nutrient for bone health do to its ability to regulate calcium and phosphate in the bloodstream. New and ongoing research is supporting that vitamin D receptors are present in the majority of tissue cells in the body, and that vitamin D is involved in many more processes in the body than previously thought. Ongoing research supports that vitamin D deficiency is linked to diseases such as alzheimer's disease, cancer, depression, heart disease, multiple sclerosis, obesity and others.