The only vitamin that the human body can produce naturally is the vitamin D or calciferol. It is synthesized in the human body mainly on skin exposed to the ultraviolet rays of the sun. The vitamin plays a vital role in keeping many diseases at bay and can be considered to be one of the more important essential nutrients that boost life expectancy and help prevent illnesses.
The connection between bone health and vitamin D is well known; the vitamin also helps prevent rickets in children, and is an essential requirement for proper tooth mineralization in the human body - it also fights osteomalacia or bone mineral loss in adults. What is less well known is that almost all human cells have a receptor for this vitamin - meaning that the vitamin plays other roles at the cellular level. Research has now confirmed that the essential vitamin D is a vital chemical regulator in processes such as cell differentiation, in apoptosis - natural and programmed cell death, as well as in tissue regeneration and renewal like the formation of new blood vessels in different tissues.
The calciferol compounds are a group of related chemicals and are found in different chemical forms in the body, but what is called, vitamin D exists as two main chemical forms which are active and stored in the body. The two main forms of vitamin D are the vitamin D2 and the vitamin D3. Both of these forms are available from food sources or from supplementary products. The form of the vitamin D called D3 is in addition, synthesized in the cells of human skin exposed to ultra violet light from the sun. This is the reason that a deficiency of vitamin D is quite rare.
Vitamin D was found to have far reaching effects in many cellular processes operating in the human body. This fact was brought out during a study by epidemiologists in the US during the 1980's, who found that the significantly higher mortality rates from colon cancer that affected populations of the northeast United States and Canada compared to states in the west, south, and southwest United States was linked in some way to vitamin D. This seminal study was the first well documented scientific study that confirmed a link between vitamin D intake and cancer. The finding would usher in many new clinical studies that tried to find other links between the vitamin D and different disorders affecting the human body.
Based on the results of this study and other clinical studies, the conclusion that many clinical scientists world wide would draw was that the onset of some types of cancers can be prevented by periodic exposure to bright sunshine, which results in the production of vitamin D in the skin. This connection between adequate exposure to sunshine and certain cancers was confirmed in the course of a study conducted by British epidemiologists in 2001, where it was found that males who on average experienced much lower exposure to sunshine tended to be affected by prostate cancer at a much younger age compared to their peers in similar age groups.
The greatest amount of beneficial vitamin D can be created in the body by exposing the skin to direct sunlight on sunny days. Exposing the hands, the face, and the arms for ten to fifteen minute periods several times each week will ensure the production of sufficient amounts of vitamin D. The use of sun screen will defeat the purpose of this exposure.
While it is mainly people living in the extreme northern regions of the world or those near the poles who tend to suffer from vitamin D deficiency, there are certain groups of people who may be very vulnerable to developing a deficiency. These include the individuals with darker skin tones, the immobile elderly, and those invalids or other individuals forced to stay at home for long periods of time.
According to the clinical studies conducted on patients in Norway, exposure to sunlight is a decisive factor for many patients. The Norwegian clinicians in the study suggest that exposure to sunlight after diagnosis can affect mortality rate in patients diagnosed with cancer. These researchers studied the mortality rate in more than twenty seven thousand men and women affected by colon cancer - they observed that the morality rate for patients was lower by twenty to thirty percent if their cancer was diagnosed during the summer or fall of the year, when compared to patients who were diagnosed with cancer in the spring or winter months. Such findings have also been reported for patients suffering from other types of cancers in the body. These results need further investigation.
At the same time, vitamin D intake has also been linked with multiple sclerosis cases in certain regions of the world. Researchers have found that populations living in the countries in Northern Europe and in Canada register the greatest incidence of multiple sclerosis in the world. Cases of multiple sclerosis in the Canadian population for example, are about four times that of the population in the states of the southern United States; the factor responsible for the increased susceptibility of the Canadian population to multiple sclerosis has to be found out. Clinical research conducted recently has suggested that in some cases of multiple sclerosis, the vitamin D may have immune and disease-modulating effects that may be potentially beneficial for patients who suffer from the disorder.
Vitamin D has also been linked to other disorders in clinical studies. The vitamin D has been connected in several studies to be linked in an inverse relationship to type I diabetes in certain individuals affected by the disorder. This connection between the vitamin D and diabetes was confirmed during the course of a singular Finnish cohort study where clinicians followed a group of children right from birth all the way through to adulthood in a long term study. Children who had received high doses of vitamin D while growing up actually fared much better and their risk of developing type I diabetes fell by eighty percent compared to the others in the group. The results of this Finnish study has been confirmed by a recently conducted meta analysis of the results, it is now held that supplements of the vitamin D given regularly during childhood will greatly lower the risk of the disorder developing in an adult.
As sunlight is weak at near the poles, vitamin D supplements are often necessary for people who live in areas north of the thirty seventh degrees latitude. People living in such places must maximize vitamin D intake as the skin may never produce enough vitamin D in these regions. A minimum daily requirement of about one thousand IU vitamin D per person is believed to be necessary for health by many clinicians and the Canadian Cancer Society. This level of vitamin D intake is needed by the body from different sources which can include the diet, exposure to sunshine or the use of supplements, particularly in the fall and winter months. Women who are nursing babies have also been recommended to take about 2,000 IU a day of vitamin D by the Canadian pediatric society.
To reach the ideal intake amount of 1,000 IU a day of vitamin D, it would be necessary for most people to use some form of supplementation. The vitamin D is found in significant quantities in only a few food sources. Some food products are particularly rich in the vitamin D, for example, taking about one Tbsp or fifteen ml of cod liver oil or even a single serving of wild salmon can easily meet the daily recommended intake level. However, taking such foods is not always possible and most people will need supplements to meet the recommended intake level. Most calcium mineral supplements contain the vitamin D as part of the supplement, vitamin D is also found in all multivitamin supplements sold in the market, and vitamin D by itself can also be found at many drug stores. Ideally supplements that include vitamin D in the D3 form must be taken for the best results. As high doses of the vitamin D can turn toxic in the body of children; extra precautions must be taken to ensure that only the correct dosage is given during the supplemental regimen.
Vitamin D has proven to be an excellent supplement for preventing the onset of many disorders. The vitamin cannot and should not be considered to be a cure for multiple sclerosis or cancer, or even childhood diabetes. It has to be looked at as a holistic supplement that endows some measure of protection against the specific diseases that can develop in the human body. This in itself makes it a unique nutrient.