Editing 7-Dehydrocholesterol (section)

== Sources ==
7-DHC can be produced by animals and plants via different pathways. It is not produced by fungi in significant amounts. It is made by some [[algae]], but the pathway is poorly understood.<ref>{{cite journal | vauthors = Jäpelt RB, Jakobsen J | title = Vitamin D in plants: a review of occurrence, analysis, and biosynthesis | journal = Frontiers in Plant Science | volume = 4 | pages = 136 | date = 2013 | pmid = 23717318 | pmc = 3651966 | doi = 10.3389/fpls.2013.00136 | doi-access = free}}</ref>

Industrially, 7-DHC generally comes from [[lanolin]], and is used to produce vitamin D3 by UV exposure.<ref name="Holick05">{{cite journal | vauthors = Holick MF | title = The vitamin D epidemic and its health consequences | journal = The Journal of Nutrition | volume = 135 | issue = 11 | pages = 2739S–2748S | date = November 2005 | pmid = 16251641 | doi = 10.1093/jn/135.11.2739S | quote = [Vitamin D3] is produced commercially by extracting 7-dehydrocholesterol from wool fat, followed by UVB irradiation and purification [...] [Vitamin D2] is commercially made by irradiating and then purifying the ergosterol extracted from yeast | doi-access = free }}</ref> [[Lichen]] ([[Cladonia rangiferina]]) is used to produce [[vegan]] D3.<ref>{{cite web |title=Vitamin D |url=https://www.vegansociety.com/resources/nutrition-and-health/nutrients/vitamin-d |website=The Vegan Society |language=en}}</ref><ref>{{cite journal |last1=Gangwar |first1=Gourvendra |title=Formulation of Lichen Based Pill a Natural Source of Vitamin D3 with a High Absorption Rate by Ambrosiya Neo-Medicine Pvt. Ltd |journal=International Journal of Biomedical Investigation |date=1 July 2023 |page=1 |url=https://openj.edwiserinternational.com/index.php/ijbi/article/download/102/101}}</ref>

7-DHC is used for vitamin D3 synthesis via [[lanosterol]] in land animals, via [[cycloartenol]] in plants, and in algae together with another provitamin D [[ergosterol]] for D2. In fungi solely ergosterol is used for synthesis of D2 via lanosterol.<ref>{{cite journal|last1=Göring |first1=Horst |title=Vitamin D in Nature: A Product of Synthesis and/or Degradation of Cell Membrane Components |url=https://www.researchgate.net/publication/328961025 |date=November 2018 |journal=Biokhimiya (Moscow) |volume=83 |issue=11 |pages=1350–1357 |doi=10.1134/S0006297918110056 |pmid=30482146 |s2cid=53437216 |access-date=December 2, 2023}}</ref>