View source for Fat soluble vitamins

{{Merge|Vitamin|date=June 2007}}

Fat-soluble vitamins necessary to the human body as well as other mammals for daily repair and functioning of body organs.<ref>[http://www.vivo.colostate.edu/hbooks/pathphys/misc_topics/vitamins.html Colorado State University, Vitamin Introduction and Index]</ref>
These are vitamins that are stored in body fat and also dissolve in body fat as opposed to  water-soluble vitamins which dissolve in water and are not stored in the body. 
==List of fat soluble vitamins==
*[[Vitamin A]]: The tolerable upper intake level for adults is 3,000 mcg RAE.
*[[Vitamin D]]: The tolerable upper intake level is set at 50 mcg for people 1 year of age and older.
*[[Tocopherol|Vitamin E]]: The tolerable upper intake levels for vitamin E varies. Large doses of vitamin E pose a hazard to people who take blood-thinning medications. 
*[[Vitamin K]]: The tolerable upper intake level has not been established for vitamin K, excessive amounts can cause the breakdown of red blood cells and liver damage. Large doses are not advised.<ref>[http://www.ext.colostate.edu/pubs/foodnut/09315.html Colorado State University Extension]</ref>

The fat soluble vitamins are absorbed from the terminal ileum, and so pathology at this location can lead to their deficiency (e.g. [[ileal resection]], [[Crohn's disease]]). They can also become deficient in poor diets, malabsorption (e.g. cystic fibrosis) and obstructive jaundce (bile is required in the duodenum/ileum to facilitate fat absorption).

Fat soluble vitamins are mostly found in fatty foods and fish-liver oils and are particularly rich in [[vitamins]] A and D. A certain amount of fat is needed in the diet to help the body absorb these vitamins. Vitamins A and D are also found in human liver and if the diet contains more vitamin A or D than is immediately required the surplus is stored in the liver. Enough of these vitamins is stored in the liver of a well-nourished person to satisfy the body's needs for several months if they are absent from the diet. If the diet contains too much vitamin A or D, however, the surplus will accumulate in the liver and may be harmful. Such excessive intakes are less likely to result from over-eating than through over-enthusiastic use of vitamin pills or dietary [[supplements]].

==References==
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[[da:Fedtopløselige vitaminer]]
[[ja:脂溶性ビタミン]]
[[pt:Vitamina lipossolúvel]]
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