Vitamin D is a fat soluble family of compounds known as Vitamins D1, D2 and D3. It is obtained from some foods, but it is normally made in the skin through the action of sunlight. Sunlight strikes the skin and the ultra violet rays convert the cholesterol, via the liver, into Vitamin D.
The problem today is that more and more people are eating the wrong types of fats which oxidise after the sun's rays have penetrated the skin. There are a number of different types of fats and cholesterol. The best type of cholesterol is HDL, which stands for high-density lipoprotein. There is LDL, which is low-density lipoprotein, and then the very worst offender, VLDL, which is very low lipoprotein. The best type of fat that you can consume is olive oil. The worst type is any hydrogenated oil. Following closely is any heated saturated or polyunsaturated fat. When the wrong type of fat is oxidised it can cause some very serious health problems. Unfortunately these days the sun is blamed for some forms of cancer, not the fat. The 'slip, slop, slap' has taken Australia by storm and consequently more people are staying indoors or covering up so much when they are outdoors that they are not receiving adequate amounts of sunshine. This can lead to diminished levels of Vitamin D.
In cases of Vitamin D deficiency, the body increases production of a hormone that removes calcium from the bones. In children, this can result in rickets. Other signs and symptomes can include hearing loss, which is due to the softening of the bones in the inner ear. Senile osteoporosis and tooth decay can also result. Vitamin D deficiency is known to be associated in osteoporosis, diabetes, high blood pressure, stroke, heart disease, depression, body muscle mass wasting, gum disease, & certain forms of cancer. Our bodies need Vitamin D to efficiently absorb calcium and phosphorous from the gut. Older people may be at risk of Vitamin D deficiency as they do not absorb or manufacture the Vitamin D in their bodies as well as a younger person can. Generally speaking younger people will have more opportunity for sun exposure than an elderly person. Others at risk of deficiency include alcoholics, those with absorption problems and people living in very cold climates. Vitamin D is converted in the liver and kidneys to its active form so sufferers of liver and kidney diseases may also be at risk if a deficiency. Vitamin D also helps prevent Calcium and some other minerals from being excreted via the kidneys.
Vitamin D can be stored in the fat cells of the liver, skin, brain and bones in sufficient amounts for many months but this is assuming the person has had the maximum amount of sun exposure. Babies under 12 months of age have stores of Vitamin D which have accumulated while they have been in the womb, providing of course that the mother has been exposed to adequate amounts sunshine during pregnancy.
The production of Vitamin D can be blocked by such things as smog, fog, sunscreen, tinted windows, glasses and protective clothing. Ensure that you are wise when being exposed to the sun. Don't get burnt!