EPA (n3) and AA (n6) both compete for use of the delta-5- desaturase enzyme to be synthesized. Increased dietary intake of animal fats alters fatty acid metabolism in favor of inflammation. There are many chronic diseases associated with elevations of this ratio including cardiovascular disease, mood disorders, and cancer. Increasing dietary intake of fish oils, or omega-3 fatty acid containing foods such as flax, chia, oily fish, or walnuts, can shift delta-5-desaturase activity toward the metabolism of the more beneficial n-3 metabolites.

Decreasing intake of animal fats is also recommended.

References:

- Tutino V, De Nunzio V, Caruso MG, et al. Elevated aa/epa ratio represents an inflammatory biomarker in tumor tissue of metastatic colorectal cancer patients. International Journal of Molecular Sciences. 2019;20(8):2050.

- Rizzo AM, Corsetto PA, Montorfano G, et al. Comparison between the AA/EPA ratio in depressed and non depressed elderly females: omega-3 fatty acid supplementation correlates with improved symptoms but does not change immunological parameters. Nutrition journal. 2012;11(1):82.

- Adams PB, Lawson S, Sanigorski A, Sinclair AJ. Arachidonic acid to eicosapentaenoic acid ratio in blood correlates positively with clinical symptoms of depression. Lipids. 1996;31(1Part2):S157-S161.

- Harris WS, Assaad B, Poston WC. Tissue omega-6/omega-3 fatty acid ratio and risk for coronary artery disease. The American journal of cardiology. 2006;98(4):19-26.

- Rupp H, Wagner D, Rupp T, Schulte L-M, Maisch B. Risk Stratification by the “EPA+ DHA Level” and the “EPA/AA Ratio”. Herz. 2004;29(7):673-685.

- Sorgi PJ, Hallowell EM, Hutchins HL, Sears B. Effects of an open-label pilot study with high-dose EPA/DHA concentrates on plasma phospholipids and behavior in children with attention deficit hyperactivity disorder. Nutrition journal. 2007;6(1):16.