Please forward this error screen to 144. Cholecalciferol and ergocalciferol can be ingested d&d 4e into the unknown pdf the diet and from supplements. Only a few foods contain vitamin D.
Calcitriol also has other effects, including some on cell growth, neuromuscular and immune functions, and reduction of inflammation. Vitamin D supplements are given to treat or to prevent osteomalacia and rickets, but the evidence for other health effects of vitamin D supplementation in the general population is inconsistent. Note double bond at top center. These are known collectively as calciferol.
In the developed world, this is a rare disease. Nutritional rickets exists in countries with intense year-round sunlight such as Nigeria and can occur without vitamin D deficiency. Although rickets and osteomalacia are now rare in Britain, outbreaks have happened in some immigrant communities in which osteomalacia sufferers included women with seemingly adequate daylight outdoor exposure wearing Western clothing. The dietary risk factors for rickets include abstaining from animal foods. Vitamin D deficiency remains the main cause of rickets among young infants in most countries, because breast milk is low in vitamin D and social customs and climatic conditions can prevent adequate sun exposure.
In sunny countries such as Nigeria, South Africa, and Bangladesh, where rickets occurs among older toddlers and children, it has been attributed to low dietary calcium intakes, which are characteristic of cereal-based diets with limited access to dairy products. 500 children had mild rickets in the late 1920s. D coincided with a dramatic decline in the number of rickets cases. Also, in the United States and Canada, vitamin D-fortified milk, infant vitamin supplements, and vitamin supplements have helped to eradicate the majority of cases of rickets for children with fat malabsorption conditions. Osteomalacia reduces calcium absorption and increases calcium loss from bone, which increases the risk for bone fractures. Dark-skinned people living in temperate climates have been shown to have low vitamin D levels but the significance of this is not certain. Dark-skinned people may be less efficient at making vitamin D because melanin in the skin hinders vitamin D synthesis.
The effects of vitamin D supplementation on health are uncertain. A 2013 review did not find any effect from supplementation on the rates of disease, other than a tentative decrease in mortality in the elderly. Low vitamin D levels may result from disease rather than cause disease. D intake and were often conflicting. Some researchers claim the IOM was too definitive in its recommendations and made a mathematical mistake when calculating the blood level of vitamin D associated with bone health. Members of the IOM panel maintain that they used a “standard procedure for dietary recommendations” and that the report is solidly based on the data.
Research on vitamin D supplements, including large-scale clinical trials, is continuing. High blood levels appear to be associated with a lower risk of death, but it is unclear if supplementation can result in this benefit. Both an excess and a deficiency in vitamin D appear to cause abnormal functioning and premature aging. The relationship between serum calcifediol level and all-cause mortality is parabolic.
Harm from vitamin D appears to occur at a lower vitamin D level in the black population than in the white population. Its general use for prevention of this disease in those without vitamin D deficiency is thus likely not needed. For older people with osteoporosis, taking vitamin D with calcium may help prevent hip fractures, but it also slightly increases the risk of stomach and kidney problems. Supplementation with higher doses of vitamin D, in those older than 65 years, may decrease fracture risk. The effect may be smaller for people living independently than for people in institutions. Use of vitamin D in children with normal vitamin D levels does not appear to improve bone density.