16 February 2014 :: In a weekly Poll survey by Lenseye.co, 86 % people says, Exposure to sunlight helps a person improve his health because the ultraviolet rays convert skin oil into Vitamin D, whereas 14 % said the pigment cells in the skin get stimulated and produce a healthy tan. The Question of the Weekly Poll was Exposure to sunlight helps a person improve his health because
The Nominees were : the infrared light kills bacteria in the body, resistance power increases, the pigment cells in the skin get stimulated and produce a healthy tan, the ultraviolet rays convert skin oil into Vitamin D
Vitamin D is a group of fat-soluble secosteroids responsible for enhancing intestinal absorption of calcium, iron, magnesium, phosphate and zinc. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol). Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements. The body can also synthesize vitamin D (specifically cholecalciferol) in the skin, from cholesterol, when sun exposure is adequate (hence its nickname, the “sunshine vitamin”).Synthesis from exposure to sunlight, as well as intake from the diet, generally contribute to the maintenance of adequate serum concentrations. Evidence indicates the synthesis of vitamin D from sun exposure is regulated by a negative feedback loop that prevents toxicity, but, because of uncertainty about the cancer risk from sunlight, no recommendations are issued by the Institute of Medicine, USA, for the amount of sun exposure required to meet vitamin D requirements. Accordingly, the Dietary Reference Intake for vitamin D assumes no synthesis occurs and all of a person’s vitamin D is from food intake, although that will rarely occur in practice. Beyond its use to prevent osteomalacia or rickets, the evidence for other health effects of vitamin D supplementation in the general population is inconsistent. The best evidence of benefit is for bone health. The effect of vitamin D supplementation on mortality is not clear, with one meta-analysis finding a decrease in mortality in elderly people, and another concluding there is no clear justification for recommending vitamin D.