answers: the skin
context: been destroyed. The modified oil cured the sick dogs, so McCollum concluded the factor in cod liver oil which cured rickets was distinct from vitamin A. He called it vitamin D because it was the fourth vitamin to be named. It was not initially realized that, unlike other vitamins, vitamin D can be synthesised by humans through exposure to UV light. In 1925, it was established that when 7-dehydrocholesterol is irradiated with light, a form of a fat-soluble vitamin is produced (now known as D). Alfred Fabian Hess stated: "Light equals vitamin D." Adolf Windaus, at the University of Göttingen </s> Vitamin D Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and multiple other biological effects. In humans, the most important compounds in this group are vitamin D (also known as cholecalciferol) and vitamin D (ergocalciferol). Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements. Only a few foods contain vitamin D. The major natural source of the vitamin is synthesis of cholecalciferol in the skin from cholesterol through a chemical reaction that is dependent on sun exposure (specifically UVB radiation). Dietary recommendations typically assume that all of </s> been observed that while serum or blood plasma concentrations follow a circadian rhythm or reflect short-term dietary impact, content within tissues is more stable and can give a better view of the availability of ascorbate within the entire organism. However, very few hospital laboratories are adequately equipped and trained to carry out such detailed analyses. The vast majority of animals and plants are able to synthesize vitamin C, through a sequence of enzyme-driven steps, which convert monosaccharides to vitamin C. Yeasts do not make -ascorbic acid but rather its stereoisomer, erythorbic acid In plants, this is accomplished through the conversion
question: where is vitamin d produced in the body