Main Difference – Omega 3 vs Omega 6 vs Omega 9
Name of a fatty acid is determined by the location of the first double bond, counted from the methyl end, that is, the omega (ω-) or the n- end. Based on this, there are three types of fatty acids known as Omega 3, Omega 6, and Omega 9. Omega-3 fatty acids are polyunsaturated fatty acids with a double bond at the third carbon atom from the end of the carbon chain. Omega-6 fatty acids and omega-9 fatty acids are polyunsaturated fatty acids with a double bond at the six carbon atom and the ninth carbon atom from the end of the carbon chain, respectively. This is the key difference between Omega 3, 6 and 9. This article explores the differences in chemical and physical properties among Omega 3, 6 and 9.
Difference Between Omega 3 6 and 9
The difference between Omega 3 6 and 9 fatty acids can be classified into following categories.
Position of the first double bond
Omega 3 fatty acids: First double bond appears at the third carbon atom from the methyl end of the carbon chain.
Omega 6 fatty acids: First double bond appears at the six carbon atom from the methyl end of the carbon chain.
Omega 9 fatty acids: First double bond appears at the ninth carbon atom from the methyl end of the carbon chain.
Alternative Names
Omega 3 fatty acids: ω-3 fatty acids, n-3 fatty acids.
Omega 6 fatty acids: ω-6 fatty acids, n-6 fatty acids.
Omega 9 fatty acids: ω−9 fatty acids, n−9 fatty acids.
Common Examples
Omega 3 fatty acids: α-linolenic acid (ALA) – (18 carbons and 3 double bonds), eicosapentaenoic acid (EPA) – (20 carbons and 5 double bonds), and docosahexaenoic acid (DHA) – (22 carbons and 6 double bonds) and these fatty acids cannot be efficiently synthesized by the human body.
Omega 6 fatty acids: Linoleic acid (18:2, n−6), Gamma-linolenic acid (GLA), Arachidonic acid (AA)
Omega 9 fatty acids: Oleic acid (18:1, n−9), Erucic acid (22:1, n−9)
Common Sources
Omega 3 fatty acids: Walnuts, edible seeds, flaxseed oil clary sage seed oil, algal oil, Echium oil, Sacha Inchi oil, and hemp oil are plant sources of Omega 3. Sources of animal omega-3 EPA and DHA fatty acids include fish oils, egg oil, squid oils, krill oil, Marine algae and phytoplankton.
Walnuts
Omega 6 fatty acids: Poultry, eggs, nuts, cereals, durum wheat, whole-grain bread, most vegetable oils, Marine algae and phytoplankton.
Cereals are a source of Omega 6.
Omega 9 fatty acids: Olive oil, macadamia oil, Canola oil, rapeseed, wallflower seed, and mustard seed are sources of Omega 9 fatty acids.
Olive oil
Essential Fatty Acids
Omega 3 fatty acids are considered as essential fatty acids. Thus humans must consume them in their diet.
Omega 6 fatty acids: Linoleic acid (LA) is considered as essential omega 6 fatty acids. Thus humans must consume them in their diet.
Omega 9 fatty acids: These are not considered as essential fatty acids. We can create the Omega 9 fatty acids from unsaturated fat in their diet.
Health Effects
Omega 3 fatty acids: Omega 3 fatty acids are associated with various positive health benefits. They can reduce the risk of cancer development and rheumatoid arthritis, and prevent, cardiovascular disease, platelet aggregation, and hypertension. They also help to reduce LDL cholesterol and increase HDL cholesterol. They can lower markers of inflammation in the blood such as C-reactive protein and interleukin 6. Omega 3 supplements are given to autism children and Alzheimer’s diseases patients.
Omega 6 fatty acids: Omega 6 fatty acids are considered as pro-inflammatory and anti-inflammatory polyunsaturated fatty acids. Thus, omega-6 and omega-3 be consumed in a balanced proportion such as 1:1 to 1:4 ratios.
Omega 9 fatty acids: Oleic acid (18:1, n−9) is an Omega 9 fatty acids and is considered as a monounsaturated fatty acid. It is associated with several health benefits, which mainly include reducing the risk of cancer development and prevention cardiovascular disease, platelet aggregation and hypertension.
Omega 3-6-9 fatty acids have several roles in the human body. In a nutritional standpoint, Omega 3-6-9 fatty acids are better than saturated fatty acids.
References
- Okuyama, H., Ichikawa, Y., Sun, Y., Hamazaki, T. and Lands, W.E.M. (2006). ω3 Fatty Acids Effectively Prevent Coronary Heart Disease and Other Late-Onset Diseases – The Excessive Linoleic Acid Syndrome. In Okuyama, H. Prevention of Coronary Heart Disease. World Review of Nutrition and Dietetics. pp. 83–103.
- Ricciotti, Emanuela and FitzGerald, Garret, A. (2011). Prostaglandins and inflammation. American Heart Association Journal, 31(5): 986–1000.
- Scorletti, E. and Byrne, C. D. (2013). Omega-3 fatty acids, hepatic lipid metabolism, and nonalcoholic fatty liver disease. Annual review of nutrition, 33(1): 231–48.
- Vafeiadou K, Weech M, Altowaijri H, et al. Replacement of saturated with unsaturated fats had no impact on vascular function but beneficial effects on lipid biomarkers, E-selectin, and blood pressure: results from the randomized controlled Dietary Intervention and VAScular function (DIVAS) study. Am J Clin Nutr. 2015 Jul;102(1):40-8.
- De Souza RJ, Mente A, Maroleanu A, et al. Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies. BMJ 2015; 351:1-16.
