It was called Suncure. Until the discovery of antibiotics 80 years ago it was next to the residence at high altitude, the only known effective treatment for tuberculosis. No one knew why it worked. It was clear only that many consumptive were healthy when they made a cure in a sunny location.
Vitamin D was in 1922 identified. The term "vitamin D" one summarizes usually two very similar molecules - Vitamin D3 and vitamin D2. Neither of the two molecules as such has been a function in the human metabolism. Each has still to be modified or chemically.
There is evidence that vitamin D and cancer prevention has an important regulator of the immune system and that many of us too little of it in their blood. There is increasing evidence that vitamin D deficiency, and he may be small, a range of negative consequences that often occur later in life. Accordingly, a deficiency contributes to the micronutrient may be the blame for a series of illnesses - including cancer, multiple sclerosis, and even infectious diseases like influenza Autoimmunund. The course of disease and the symptom relapses in MS patients also show regular seasonal variations - with a maximum in spring, when the blood level is of 25D after the winter at the lowest, and a minimum in autumn, when the high sun in summer, the supply of vitamin D3 has increased sharply.
Vitamin D3 is in contact with UV-B radiation (at a wavelength of 315-280 nanometers) of certain skin cells called keratinocytes produced. In this context, the increased public awareness of the risks of sunbathing is problematic. Modern sunscreens reduce vitamin D produced in the skin by more than 98 percent. To meet the normal requirements of the micro-nutrient, should people with fair skin or bronze color in North America or Europe take daily in the summer sun an unprotected 5 to 15 minutes between 10.00 und 15.00 clock. It comes more than a slight pink color of the skin. A vitamin D toxicity by sunlight has not been observed. A fair-skinned woman in a bikini in the summer sun takes a form, in 15 to 20 minutes, about 100 000 IU vitamin D. After this value has stagnated, however, because UV radiation can also break down the vitamin - which prevents too much which forms in the skin. Accordingly, if there is enough exposure to sunlight, we need not take it with food.
According to most researchers in the field has a significant number of people in the temperate latitudes, especially in winter vitamin D levels far below the optimal level of health. The reason is that occur outside the tropics in the summer of larger amounts of UVB radiation. In line with this, there is a clear correlation between increasing latitude and the risk for certain diseases.
Vitamin D2 is derived from a cholesterol-like plant steroid and is found in few foods, such as shiitake mushrooms, dairy products, egg yolks, fatty fish or whale oil - and now from dietary supplements.
Recent studies show also a correlation between the disease risk and the concentration of free blood in the 25D. Illustrating such a study of 420 healthy women from Copenhagen (55 degrees north), Helsinki (60 degrees), Cork (52 degrees) and Warsaw (52 degrees) in February and March 2005. In 92 percent of young girls in this sample of the 25D-level was below 20 and at 37 percent below 10 nanograms per milliliter (a severe vitamin D deficiency). In that case, other sources of vitamin D are crucial.
Even with vitamin D supplements can prevent a lack of course. The amount of the daily dose is controversial. After evaluating several studies on the relationship between vitamin D intake and 25DProduktion last year, they are of the opinion that half of all adults in the United States at least 1000 international units of vitamin D3 would have to take a day to its 25D-serum concentration on what is necessary for the health minimum level of 30 nanograms per milliliter to bring. Unfortunately, there is no general rule of thumb for the 25D-production by vitamin D supplements because they are individually very different and also depends on the degree of deprivation. Although you can give with vitamin D supplements and a harmful overdose - but usually only for taking away at least 40 000 international units a day for a long time.
A unanimous recommendation of a sensible sun exposure on the part of the medical profession and a clear statement about the optimal dose and how it is achieved, could help to further improve the health of the world's population significantly.
Source: Spektrum der Wissenschaft, Juli 2008
Holick, MF: Vitamin D defi-ciency.
