Numerous epidemiologic studies suggest that exposure to sunlight, which enhances the production of vitamin D
(colecalciferol) in the skin, is important in preventing many diseases such as osteoporosis, osteoarthritis, rickets, type 1 diabetes, cancers, immune system disorders and heart disease.
Because very few foods naturally contain vitamin D, sunlight supplies most of our vitamin D requirement. The more skin we expose the more vitamin D is produced.The increasing worldwide displacement from the natural outdoor environment of human beings to an indoor sedentary lifestyle, has resulted in a global pandemic of vitamin D insufficiency.
Vitamin D deficiency
Vitamin D deficiency presents when serum 25 hydroxyvitamin D levels fall below 20 ng/mL (50 nmol/L). Vitamin D deficiency should be aggressively treated with higher pharmacological doses with the aim of achieving serum levels above or equal to 30ng/mL (75 nmol/L). Treatment usually includes 50,000 international units of vitamin D2 or D3 by mouth once or more per week for six to eight weeks, and then 1000 (or more) international units of vitamin D3 daily thereafter.
Vitamin D Deficiency Related Diseases
Vitamin D and Osteoporosis
Vitamin D helps the body absorb calcium in the gut, aids bone growth and remodeling, and maintains correct calcium and phosphorus serum levels to sustain normal bone mineralization.
Vitamin D deficiency can precipitate osteoporosis, cause muscle weakness and increase the risk of fracture.
Vitamin D and Crohn's Disease
A study in 2013 was performed in patients with mild-to-moderate Crohn's disease. Patients were evaluated for severity of symptoms using the Crohn's disease activity index (CDAI) - CDAI is a research tool used to quantify the symptoms of patients with Crohn's disease.
Twenty-four weeks supplementation with up to 5,000 IU/d vitamin D3 effectively reduced CDAI scores in Crohn's patients
suggesting that restoration of normal vitamin D serum levels may be useful in the management of patients with mild-moderate Crohn's disease.
Vitamin D and Prostate Cancer
According to a recent research, Vitamin D consumption may lead to lowering or even reverse the progression of low-grade prostate cancer, without the need of surgery or radiation. Vitamin D decreased inflammation in tissues, and inflammation is a driver of cancer.
Men who had received 4000 IU of Vitamin-D per day for 60 days, showed improvements in their prostate tumors, whereas the placebo group either stayed the same or got worse, thus suggesting that Vitamin-D had caused dramatic changes in the expression levels of many cell lipids and proteins, particularly those involved in inflammation.
Vitamin D Supplementation in Disease Prevention
It is not clear just how much vitamin D
is needed for increased health and disease risk reduction. However, many physicians are now recommending 2,000 IU daily for most adults, and the Institute of Medicine (IOM) committee announced that 4,000 IU a day of vitamin D
appears safe for adults and kids aged 9 and up. Being at the top end of the recommended levels of vitamin D seems to be the better choice