Editing Niacin (section)

==Definition==
Niacin is both a vitamin, i.e., an essential nutrient, marketed as a dietary supplement, and in the US, a prescription medicine. As a vitamin, it is precursor of the coenzymes [[nicotinamide adenine dinucleotide]] (NAD) and [[nicotinamide adenine dinucleotide phosphate]] (NADP). These compounds are coenzymes for many dehydrogenases, participating in many hydrogen transfer processes. NAD is important in [[catabolism]] of fat, carbohydrate, protein, and alcohol, as well as cell signaling and DNA repair, and NADP mostly in [[anabolism]] reactions such as fatty acid and cholesterol synthesis.<ref name=PKIN2020Niacin/> Vitamin intake recommendations made by several countries are that intakes of 14–18&nbsp;mg/day are sufficient to meet the needs of healthy adults.<ref name="DRItext" /><ref name="EFSAtext" /><ref name=AusNZ /> Niacin but also [[nicotinamide]] are used for prevention and treatment of [[pellagra]], a disease caused by lack of the vitamin.<ref name=Hegyi2004>{{cite journal | vauthors = Hegyi J, Schwartz RA, Hegyi V | title = Pellagra: dermatitis, dementia, and diarrhea | journal = International Journal of Dermatology | volume = 43 | issue = 1 | pages = 1–5 | date = January 2004 | pmid = 14693013 | doi = 10.1111/j.1365-4632.2004.01959.x | s2cid = 33877664 | doi-access = free }}</ref><ref name=PKIN2020Niacin>{{cite book |vauthors=Penberthy WT, Kirkland JB |title = Present Knowledge in Nutrition, Eleventh Edition |chapter = Niacin |editor=BP Marriott |editor2=DF Birt |editor3=VA Stallings|editor4=AA Yates |publisher = Academic Press (Elsevier) |year=2020 |location = London, United Kingdom |pages = 209–24 |isbn=978-0-323-66162-1}}</ref> When niacin is used as a medicine to treat [[hyperlipidemia|elevated cholesterol and triglycerides]], daily doses range from 500 to 3,000&nbsp;mg/day.<ref name=DailyMed /><ref name=Niaspan /> High-dose nicotinamide does not have this medicinal effect.<ref name=PKIN2020Niacin />