Vaccenic acid (VA) is a monounsaturated omega-7 fatty acid (18:1n7).
VA is a naturally occurring trans-fat unlike those produced industrially. The trans-configuration occurs around carbon 11, therefore VA is sometimes denoted as trans11-18:1n7. Ruminant animals produce vaccenic acid in a fermentation process in their microbiome. The dairy products (cheese, milk, butter) or meat obtained from these animals contain VA. There is also a cis-configuration of vaccenic acid created by de novo lipogenesis.
VA can then be converted to an isomer of conjugated linoleic acid (CLA) using a desaturase enzyme. CLA has been associated with anti-inflammatory activity and affects lipid metabolism.184 VA, as a cis-isomer, has demonstrated associations with lower insulin resistance and decreased risk of diabetes. The trans-isomer has also been shown to be beneficial as it relates to insulin secretion and resistance.
Both isomers have been studied in vitro (and in animal studies) and may suppress adhesion molecules in the vascular endothelium. Therefore, VA isomers are being studied as possible prophylaxis in patients with risk of atherosclerosis. However, human intervention studies are limited.
References:
- Gebauer SK, Destaillats F, Dionisi F, Krauss RM, Baer DJ. Vaccenic acid and trans fatty acid isomers from partially hydrogenated oil both adversely affect LDL cholesterol: a double-blind, randomized controlled trial. The American journal of clinical nutrition. 2015;102(6):1339-1346.
- Weir NL, Johnson L, Guan W, et al. Cis-Vaccenic Acid Is Associated with Lower HOMA-IR and Incident T2D in Participants from the MESA Cohort. In: Am Diabetes Assoc; 2018.
- Wang X, Gupta J, Kerslake M, Rayat G, Proctor SD, Chan CB. Trans-11 vaccenic acid improves insulin secretion in models of type 2 diabetes in vivo and in vitro. Molecular Nutrition & Food Research. 2016;60(4):846-857.
- Wang X, England A, Sinclair C, Merkosky F, Chan CB. Trans-11 vaccenic acid improves glucose homeostasis in a model of type 2 diabetes by promoting insulin secretion via GPR40. Journal of Functional Foods. 2019;60:103410.
- Abbasi A, Mostafaie A, Bahrami G, Mansouri K, Sisakhtnejad S. The effect of Cis and Trans vaccenic acids on expression of ICAM-1 and VCAM-1 in human microvascular endothelial cells (HMEC). Journal of Reports in Pharmaceutical Sciences. 2015;4(1):65-74.
Vaccenic 18:1 n7
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