Editing Α-Linolenic acid (section)

==Metabolism==
[[Image:Beklädnadsväxter, Linum usitatissimum, Nordisk familjebok.png|thumb|100px|right|[[Flax]] is a rich source of α-linolenic acid.]]

α-Linolenic acid can be obtained by humans only through their diets.  Humans lack the [[desaturase]] enzymes required for processing [[stearic acid]] into A-linoleic acid or other unsaturated fatty acids. 

Dietary α-linolenic acid is metabolized to [[stearidonic acid]], a precursor to a collection of polyunsaturated 20-, 22-, 24-, etc fatty acids ([[eicosatetraenoic acid]], [[eicosapentaenoic acid]], [[docosapentaenoic acid]], tetracosapentaenoic acid, [[nisinic acid|6,9,12,15,18,21-tetracosahexaenoic acid]], [[docosahexaenoic acid]]).<ref>{{cite journal |author1=Breanne M Anderson |author2=David WL Ma | year = 2009 
| title = Are all n-3 polyunsaturated fatty acids created equal? | pages = 33 
| journal = Lipids in Health and Disease 
| volume = 8 
| issue = 33 
| doi = 10.1186/1476-511X-8-33 |doi-access=free|pmid=19664246 |pmc=3224740 }}</ref> 
Because the efficacy of ''n''−3 long-chain polyunsaturated fatty acid (LC-PUFA) synthesis decreases down the cascade of α-linolenic acid conversion, DHA synthesis from α-linolenic acid is even more restricted than that of EPA.<ref>{{cite journal
| author=Shiels M. Innis
| year = 2007
| title = Fatty acids and early human development
| journal = [[Early Human Development]]
| volume = 83
| pages = 761–766
| doi = 10.1016/j.earlhumdev.2007.09.004
| pmid=17920214
| issue=12
}}</ref> Conversion of ALA to DHA is higher in women than in men. This is likely due to the increased need for DHA in women in order to support a developing fetus and in producing breastmilk containing DHA.<ref name=":0">{{cite journal | last1 = Burdge | first1 = GC | last2 = Calder | first2 = PC | title = Conversion of alpha-linolenic acid to longer-chain polyunsaturated fatty acids in human adults | journal = Reproduction, Nutrition, Development | volume = 45 | issue = 5 | pages = 581–597 | year = 2005 | pmid = 16188209 | doi = 10.1051/rnd:2005047 | url = http://rnd.edpsciences.org/articles/rnd/pdf/2005/05/r5505.pdf | doi-access = free | access-date = 4 November 2018 | archive-date = 15 August 2017 | archive-url = https://web.archive.org/web/20170815122704/https://rnd.edpsciences.org/articles/rnd/pdf/2005/05/r5505.pdf | url-status = live }}</ref>

===Stability and hydrogenation===
Compared to many other oils, α-linolenic acid is more susceptible to oxidation. It [[rancidification|becomes rancid]] more quickly in air. [[Rancidification|Oxidative instability]] of α-linolenic acid is one reason why producers choose to partially [[Hydrogenation|hydrogenate]] oils containing α-linolenic acid, such as [[soybean oil]].<ref name= Kinney >{{cite web
 |author=Kinney, Tony 
 |title=Metabolism in plants to produce healthier food oils (slide #4) 
 |url=http://www.metabolicengineering.gov/me2005/Kinney.pdf 
 |access-date=2007-01-11 
 |url-status=dead 
 |archive-url=https://web.archive.org/web/20060929134832/http://www.metabolicengineering.gov/me2005/Kinney.pdf 
 |archive-date=29 September 2006 
}}</ref> [[Soybean]]s are the largest source of edible oils in the U.S., and, as of a 2007 study, 40% of soy oil production was partially hydrogenated.<ref>{{cite journal|url=http://www.truthabouttrade.org/article.asp?id=6669 |title=Ban on trans fat could benefit Iowa |journal=Truth About Trade and Technology |access-date=2007-01-03 |author1=Fitzgerald, Anne  |author2=Brasher, Philip |url-status=dead |archive-url=https://web.archive.org/web/20070927012419/http://www.truthabouttrade.org/article.asp?id=6669 |archive-date=27 September 2007 }}</ref> 

Hydrogenation of ALA-containing fats can introduce [[trans fat]]s. Consumers are increasingly avoiding products that contain trans fats, and governments have begun to ban trans fats in food products, including the US government as of May 2018.<ref>{{Cite journal |last=Program |first=Human Foods |date=2024-09-06 |title=Trans Fat |url=https://www.fda.gov/food/food-additives-petitions/trans-fat |journal=FDA |language=en}}</ref> These regulations and market pressures have spurred the development of soybeans low in α-linolenic acid. These new soybean varieties yield a more stable oil that often do not require hydrogenation for many applications.<ref>{{cite web
 |url         = http://www.monsanto.com/monsanto/layout/media/06/01-12-06.asp
 |author      = Monsanto
 |title       = ADM to process Monsanto's Vistive low linolenic soybeans at Indiana facility
 |access-date  = 2007-01-06
 |archive-url  = https://web.archive.org/web/20061211071206/http://www.monsanto.com/monsanto/layout/media/06/01-12-06.asp
 |archive-date = 11 December 2006
 |url-status   = dead}}</ref>

===Health===
ALA is an [[essential fatty acid]], meaning consumption of ALA in the diet is required for human life,<ref>{{Cite web |title=Office of Dietary Supplements - Omega-3 Fatty Acids |url=https://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/ |access-date=2025-04-04 |website=ods.od.nih.gov |language=en}}</ref> along with all other [[Mammal|mammals]].<ref name=":0" /> ALA consumption is associated with a lower risk of [[cardiovascular disease]] and a reduced risk of fatal coronary heart disease.<ref>{{cite journal|vauthors=Sala-Vila A, Fleming J, Kris-Etherton P, Ros E|year=2022|title=Impact of α-Linolenic Acid, the Vegetable ω-3 Fatty Acid, on Cardiovascular Disease and Cognition|journal=Advances in Nutrition|url=https://academic.oup.com/advances/article/13/5/1584/6529227|volume=13|issue=5|pages=1584–1602|doi=10.1093/advances/nmac016|pmid=35170723 |pmc=9526859}}</ref><ref>{{cite journal |vauthors=Pan A, Chen M, Chowdhury R |title=α-Linolenic acid and risk of cardiovascular disease: a systematic review and meta-analysis |journal=Am. J. Clin. Nutr. |volume=96 |issue=6 |pages=1262–73 |date=December 2012  |pmid=23076616 |pmc=3497923 |doi=10.3945/ajcn.112.044040 |type=Systematic review|display-authors=etal}}</ref> Dietary ALA intake can improve lipid profiles by decreasing [[triglyceride]]s, [[total cholesterol]], [[high-density lipoprotein]], and [[low-density lipoprotein]].<ref>{{cite journal|vauthors=Hao Y, Bin Q, Min J, Wei L, Xiao-fei G, Na L, Zhi-xiang X, Fang-ling D, Tongcheng X, Duo L|year=2020|title=Effects of α-linolenic acid intake on blood lipid profiles：a systematic review and meta-analysis of randomized controlled trials|url=https://www.tandfonline.com/doi/abs/10.1080/10408398.2020.1790496|journal=Critical Reviews in Food Science and Nutrition|volume=61|issue=17|pages=2894–2910|doi=10.1080/10408398.2020.1790496|pmid=32643951|s2cid=220439436|access-date=14 December 2021|archive-date=14 December 2021|archive-url=https://web.archive.org/web/20211214200928/https://www.tandfonline.com/doi/abs/10.1080/10408398.2020.1790496|url-status=live}}</ref> A 2021 review found that ALA intake is associated with a reduced risk of mortality from all causes, cardiovascular disease, and coronary heart disease but a slightly higher risk of cancer mortality.<ref>{{cite journal|vauthors=Naghshi S, Aune D, Beyene J, Mobarak S, Asadi M, Sadeghi O|year=2021|title=Research Dietary intake and biomarkers of alpha linolenic acid and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of cohort studies|url=https://www.bmj.com/content/375/bmj.n2213|journal=The BMJ|volume=375|issue=|pages=n2213|pmid=34645650|doi=10.1136/bmj.n2213|pmc=8513503|access-date=14 December 2021|archive-date=14 December 2021|archive-url=https://web.archive.org/web/20211214185932/https://www.bmj.com/content/375/bmj.n2213|url-status=live}}</ref>