Vitamin D sufficiency, along with diet and exercise, has emerged as one of the most important preventive factors in human health. Hundreds of studies now link vitamin D deficiency with significantly higher rates of many forms conditions and diseases.
Researchers at the University of Minnesota found that vitamin D levels in the body at the start of a low-calorie diet predict weight loss success, suggesting a possible role for vitamin D in weight loss, according to Medical News Today. Further, data collected from the National Health and Nutrition Examination Survey (NHANES), found that nine percent (7.6 million) of children across the U.S. were vitamin D deficient (defined as less than 15ng/mL of blood), while another 61 percent, or 50.8 million, were vitamin D insufficient (15-29ng/mL).
Five forms of vitamin D have been discovered - vitamin D1, D2, D3, D4 and D5. The two forms that seem to matter most to humans are vitamins D2 (ergocalciferol) and D3 (cholecalciferol). Vitamin D for humans is obtained from sun exposure, food and supplements. It is biologically inert and has to undergo two hydroxylation reactions to become active in the body.
Sunlight is the best and only true natural source of vitamin D. Unlike dietary or supplementary vitamin D, when one gets 'D' from sunshine, the body takes what it needs and demetabolizes any extra. That's critical as vitamin D experts and many health groups now advocate 1,000-2,000IU of vitamin D daily - five to 10 times the old recommendations. In November, although considered conservative, the Institute of Medicine, the nation's top scientific advisory panel, increased its recommendations for vitamin D doses and extended the safe upper limit.
According to www.sunshinevitamin.org because too much 'D' from dietary supplements may cause the body to over-process calcium, nobody really knows for sure how much supplementary vitamin D is safe. While vitamin D toxicity is a reality, it is a rare phenomenon. On the other hand, sunlight induced vitamin D doesn't have that problem - it's the way the body is intended to make it. Thus, the Sunshine Vitamin Alliance has been established as a coalition of physicians, individuals and organizations who advocate natural vitamin D production through regular, non-burning sun exposure.
Additionally, despite there being very few foods in nature that contain vitamin D, there are several natural products that can help increase your vitamin D intake.