Linoleic acid (omega 6) is reputed an essential fatty acid for our body as it can be considered a bioactive lipid and can serve as a functional food as it has the ability to alter body weight and modulate metabolism.

It has a very important function in our body as it participates in cell growth and blood coagulation.

It belongs to the family of omega 6 fatty acids, it is a powerful antioxidant and acts as a contrast to fats.

Linoleic acid is the most highly consumed Polyunsaturated fatty acid (PUFA) found in the human diet. On consumption, linoleic acid has 4 primary fates. Like all fatty acids, it can be used as a source of energy. It can be esterified to form neutral and polar lipids such as phospholipids, triacylglycerols, and cholesterol esters. As part of membrane phospholipids, linoleic acid functions as a structural component to maintain a certain level of membrane fluidity of the transdermal water barrier of the epidermis. In addition, when released from membrane phospholipids, it can be enzymatically oxidized to a variety of derivatives involved in cell signaling [i.e., 13-hydroxy or 13-hydroperoxy octadecadienoic acid, 13-H(P)ODE] (1).

The main sources in which we find linoleic acid are:

• vegetable oils
• seeds
• walnuts
• eggs
• meat
• milk

It is used in:

• medicine
• cosmetics
• human nutrition
• animal feed

As a dietary supplement it is called CLA (conjugated linoleic acid).

Linoleic acid studies

Molecular Formula: C₁₈H₃₂O₂

Linear Formula CH₃(CH₂)₄CH=CHCH₂CH=CH(CH₂)₇CO₂H 

Molecular Weight: 280.452 g/mol

UNII: 9KJL21T0QJ

CAS: 60-33-3  8024-22-4  506-21-8  2197-37-7  80969-37-5  949900-18-9

EC Number: 200-470-9  606-872-4  617-024-8

FEMA Number: 3380

PubChem Substance ID 24896279

MDL number MFCD00064241

Beilstein Registry Number 1727101

Synonyms:

• 18:2ω6; cis, cis-9,12-octadecadienoic acid
• Linolic acid
• omega 6
• Telfairic acid
• all-cis-9,12-Octadecadienoic acid
• Linoleate
• Emersol 315
• Unifac 6550
• 9,12-Octadecadienoic acid (9Z,12Z)-
• 9,12-Octadecadienoic acid (Z,Z)-
• cis,cis-9,12-Octadecadienoic acid
• cis-9,cis-12-Octadecadienoic acid

References__________________________________________________

(1) Linoleic Acid

Jay Whelan

Adv Nutr. 2013 May; 4(3): 311–312.

Published online 2013 May 6. doi: 10.3945/an.113.003772

Medicine

Telmisartan Influences the Antiproliferative Activity of Linoleic Acid in Human Colon Cancer Cells.
Mielczarek-Puta M, Otto-Ślusarczyk D, Chrzanowska A, Filipek A, Graboń W.
Nutr Cancer. 2019 May 16:1-12. doi: 10.1080/01635581.2019.1613552.

Novel gene regulatory networks identified in response to nitro-conjugated linoleic acid in human endothelial cells.
Lu H, Sun J, Liang W, Zhang J, Rom O, Garcia-Barrio MT, Li S, Villacorta L, Schopfer FJ, Freeman BA, Chen YE, Fan Y.
Physiol Genomics. 2019 May 10. doi: 10.1152/physiolgenomics.00127.2018.

Redox-sensitive prodrug nanoassemblies based on linoleic acid-modified docetaxel to resist breast cancers.
Li M, Zhao L, Zhang T, Shu Y, He Z, Ma Y, Liu D, Wang Y.
Acta Pharm Sin B. 2019 Mar;9(2):421-432. doi: 10.1016/j.apsb.2018.08.008.

Biomarkers of Dietary Omega-6 Fatty Acids and Incident Cardiovascular Disease and Mortality.
Marklund M, Wu JHY, Imamura F, Del Gobbo LC, Fretts A, de Goede J, Shi P, Tintle N, Wennberg M, Aslibekyan S, Chen TA, de Oliveira Otto MC, Hirakawa Y, Eriksen HH, Kröger J, Laguzzi F, Lankinen M, Murphy RA, Prem K, Samieri C, Virtanen J, Wood AC, Wong K, Yang WS, Zhou X, Baylin A, Boer JMA, Brouwer IA, Campos H, Chaves PHM, Chien KL, de Faire U, Djoussé L, Eiriksdottir G, El-Abbadi N, Forouhi NG, Michael Gaziano J, Geleijnse JM, Gigante B, Giles G, Guallar E, Gudnason V, Harris T, Harris WS, Helmer C, Hellenius ML, Hodge A, Hu FB, Jacques PF, Jansson JH, Kalsbeek A, Khaw KT, Koh WP, Laakso M, Leander K, Lin HJ, Lind L, Luben R, Luo J, McKnight B, Mursu J, Ninomiya T, Overvad K, Psaty BM, Rimm E, Schulze MB, Siscovick D, Skjelbo Nielsen M, Smith AV, Steffen BT, Steffen L, Sun Q, Sundström J, Tsai MY, Tunstall-Pedoe H, Uusitupa MIJ, van Dam RM, Veenstra J, Monique Verschuren WM, Wareham N, Willett W, Woodward M, Yuan JM, Micha R, Lemaitre RN, Mozaffarian D, Risérus U; Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Fatty Acids and Outcomes Research Consortium (FORCE).
Circulation. 2019 May 21;139(21):2422-2436. doi: 10.1161/CIRCULATIONAHA.118.038908.

Effect of linoleic acid on ischemic heart disease and its risk factors: a Mendelian randomization study.
Zhao JV, Schooling CM.
BMC Med. 2019 Mar 14;17(1):61. doi: 10.1186/s12916-019-1293-x.

Linoleic Acid Increases Prostaglandin E2 Release and Reduces Mitochondrial Respiration and Cell Viability in Human Trophoblast-Like Cells.
Shrestha N, Cuffe JSM, Holland OJ, Perkins AV, McAinch AJ, Hryciw DH.
Cell Physiol Biochem. 2019;52(1):94-108. doi: 10.33594/000000007. Epub 2019 Feb 18

Conjugated Linoleic Acid Effects on Cancer, Obesity, and Atherosclerosis: A Review of Pre-Clinical and Human Trials with Current Perspectives.
den Hartigh LJ.
Nutrients. 2019 Feb 11;11(2). pii: E370. doi: 10.3390/nu11020370.

Inflammatory response to dietary linoleic acid depends on FADS1 genotype.
Lankinen MA, Fauland A, Shimizu BI, Ågren J, Wheelock CE, Laakso M, Schwab U, Pihlajamäki J.
Am J Clin Nutr. 2019 Jan 1;109(1):165-175. doi: 10.1093/ajcn/nqy287.

Role of linoleic acid in autoimmune disorders: a Mendelian randomisation study.
Lee YH.
Ann Rheum Dis. 2018 Dec 18. pii: annrheumdis-2018-214810. doi: 10.1136/annrheumdis-2018-214810

Omega-6 fats for the primary and secondary prevention of cardiovascular disease.
Hooper L, Al-Khudairy L, Abdelhamid AS, Rees K, Brainard JS, Brown TJ, Ajabnoor SM, O'Brien AT, Winstanley LE, Donaldson DH, Song F, Deane KH.
Cochrane Database Syst Rev. 2018 Nov 29;11:CD011094. doi: 10.1002/14651858.CD011094.pub4.

The Acute Effect of Oleic- or Linoleic Acid-Containing Meals on Appetite and Metabolic Markers; A Pilot Study in Overweight or Obese Individuals.
Naughton SS, Hanson ED, Mathai ML, McAinch AJ.
Nutrients. 2018 Sep 26;10(10). pii: E1376. doi: 10.3390/nu10101376.

Linoleic acid reduces vascular reactivity and improves the vascular dysfunction of the small mesentery in hypertension.
Nunes DO, Marques VB, Almenara CCP, Marcarini WD, Ribeiro Júnior RF, Padilha AS.
J Nutr Biochem. 2018 Dec;62:18-27. doi: 10.1016/j.jnutbio.2018.07.016.

Differentiating the biological effects of linoleic acid from arachidonic acid in health and disease.
Burns JL, Nakamura MT, Ma DWL.
Prostaglandins Leukot Essent Fatty Acids. 2018 Aug;135:1-4. doi: 10.1016/j.plefa.2018.05.004.

Low linolenic and linoleic acid consumption are associated with chronic kidney disease in patients with type 2 diabetes.
Dos Santos ALT, Duarte CK, Santos M, Zoldan M, Almeida JC, Gross JL, Azevedo MJ, Lichtenstein AH, Zelmanovitz T.
PLoS One. 2018 Aug 9;13(8):e0195249. doi: 10.1371/journal.pone.0195249

Linoleic acid, glycemic control and Type 2 diabetes.
Belury MA, Cole RM, Snoke DB, Banh T, Angelotti A.
Prostaglandins Leukot Essent Fatty Acids. 2018 May;132:30-33. doi: 10.1016/j.plefa.2018.03.001.

High erythrocyte levels of the n-6 polyunsaturated fatty acid linoleic acid are associated with lower risk of subsequent rheumatoid arthritis in a southern European nested case-control study.
de Pablo P, Romaguera D, Fisk HL, Calder PC, Quirke AM, Cartwright AJ, Panico S, Mattiello A, Gavrila D, Navarro C, Sacerdote C, Vineis P, Tumino R, Ollier WE, Michaud DS, Riboli E, Venables PJ, Fisher BA.
Ann Rheum Dis. 2018 Jul;77(7):981-987. doi: 10.1136/annrheumdis-2017-212274. Epub 2018 Feb 7

Animal feed

Linoleic acid metabolic pathway allows for an efficient increase of intramuscular fat content in pigs.
Gol S, González-Prendes R, Bosch L, Tor M, Reixach J, Pena RN, Estany J.
J Anim Sci Biotechnol. 2019 May 7;10:33. doi: 10.1186/s40104-019-0343-8.

Ruminal fatty acid outflow in dry cows fed different sources of linoleic acid: reticulum and omasum as alternative sampling sites to abomasum.
Freitas Júnior JE, Bettero VP, Zanferari F, Del Valle TA, De Paiva PG, Ferreira De Jesus E, Takiya CS, Leite LC, Dias M, Rennó FP.
Arch Anim Nutr. 2019 Jun;73(3):171-193. doi: 10.1080/1745039X.2019.1595886.

Dose response of rumen-protected conjugated linoleic acid supplementation to fattening bulls and heifers on growth, and carcass and meat quality.
Schiavon S, Cecchinato A, Pegolo S, Dannenberger D, Tagliapietra F, Bittante G.
J Anim Physiol Anim Nutr (Berl). 2019 Apr 26. doi: 10.1111/jpn.13107.

Conjugated linoleic acid regulates lipid metabolism through the expression of selected hepatic genes in laying hens.
Wang SH, Wang WW, Zhang HJ, Wang J, Chen Y, Wu SG, Qi GH.
Poult Sci. 2019 Apr 5. pii: pez161. doi: 10.3382/ps/pez161.

Conjugated linoleic acid (CLA)-induced milk fat depression: application of RNA-Seq technology to elucidate mammary gene regulation in dairy ewes.
Suárez-Vega A, Gutiérrez-Gil B, Toral PG, Hervás G, Arranz JJ, Frutos P.
Sci Rep. 2019 Mar 14;9(1):4473. doi: 10.1038/s41598-019-40881-3.

Dietary conjugated linoleic acid modulates morphology, selective immune parameters, and gene expressions in the intestine of grass carp.
Kong L, Cheng SY, Xiang XJ, Liu WS, Yu DH, Yang YO, Zhou J, Huang F, Dong GF.
Fish Shellfish Immunol. 2019 Mar;86:536-548. doi: 10.1016/j.fsi.2018.11.071. Epub 2018 Nov 30.

Protective effect of Chitosan nanoparticles against the inhibitory effect of linoleic acid supplementation on maturation and developmental competence of bovine oocytes.
Abdel-Halim BR.
Theriogenology. 2018 Jul 1;114:143-148. doi: 10.1016/j.theriogenology.2018.03.032. Epub 2018 Mar 31.