Written by Norman Lowe, Senior Technical Consultant HPC and Industrial, September 2025 

In cosmetics and nutrition, we often hear the term ‘ Omega rich’, usually applied to  polyunsaturated fatty acids (PUFAs), commonly Omega 3, 6 and 9. But what does this term actually refer to, and what are the sources of these different Omega oils?

In a fatty acid, we have a carboxylic end group (-COOH) and a long carbon chain. If there are no  double bonds in the chain (-CH2=CH2-), we refer to the fatty acid as ‘Saturated’. If there is one double bond or more, it is referred to as ‘Unsaturated’. The carbon atom closest to the  carboxylic end group is called the ALPHA carbon atom, while the carbon atom at the very end of the chain is the OMEGA carbon. Therefore an Omega 3 fatty acid has a double bond on the 3rd carbon atom from the last carbon in the chain. The same logic applies to Omega 6, with the double bond on the sixth carbon atom, and so on. 

So what effects do these different omega oils have, what are the source oils, and how do we  promote them in cosmetics and potentially nutrition?

 

Omega 3

The main fatty acids in nutrition are Docosahexaenoic acid (DHA) C22:6 and Eicosapentaenoic acid (EPA) C20:5. In nutrition, both have direct effects on the brain and cardiovascular system and provide anti-inflammatory benefits. As a topical application in cosmetics, their direct effect is perhaps minimal. However, they are very important in nutrition for brain and cardiovascular health, as well as overall body health, and are found in high levels in fish oils and algae. 

Alpha-Linolenic acid (ALA) C18:3 is a shorter-chain Omega 3 oil that is converted in the body to DHA, playing an important role in nutrition. It can be obtained from vegetable fatty oils, particularly linseed oil (flaxseed oil), grapeseed oil (70%), as well as chia seeds (25% to 30%), walnuts (14%), and hemp seeds (17%). Linseed oil contains approximately 56% to 71% ALA. In topical applications, linseed oil provides excellent emollience, reduces itching, and has anti-inflammatory properties. Grapeseed oil has less odour but is not produced in such large quantities.

In general terms, topical application of these Omega 3 oils has little direct effect on the skin. The more significant effects come from the base oils they are contained in, such as emolliency, antioxidant activity, and anti-inflammatory effects. However, the fact that these oils contain Omega 3 fatty acids is a great selling point, as public perception is that they have significant health values. From a nutritional point of view, they are essential for good health. 

HARKE UK & Ireland offers an Omega 3 oil from ICSC that is food-grade for both human and animal health. 

The same principle applies to the other Omega oils: essential in nutrition but more reliant on the base oils for their range of topical effects. 

However, it is beneficial to highlight the base oils rich in particular Omega oils.

 

Omega 6

Arachidonic acid C20:4 is found only in animal oils and fish oils, with no vegetable sources.  Nutritionally, it provides energy for body functions and contributes to cell membrane structure. We generally do not use animal oils in cosmetics; however, nutritional supplements are available on the market.

Linoleic acid C18:2 is found in various vegetable sources. Sunflower oil contains around 68%, and this is an extremely useful oil in cosmetics: a good emollient, low odour, relatively inexpensive, and used in everything from skin creams to hair conditioner. Other sources include cottonseed oil (44%), rice bran oil (37%), corn oil (42%), poppy seed oil (73%), safflower oil (73%), walnut oil (48%, as well as 16% Omega 3), and argan oil (37%). However, sunflower oil may be the most economical.

 

Omega 9

Oleic acid C18:1 is very abundant in vegetable oils, making up 84% of olive oil, 73% of sweet almond oil, and many more. Oleic acid provides excellent lubricity and emollience, making olive oil and sweet almond oil very useful in cosmetic applications.

Erucic acid C22:1 constitutes 53% of high-erucic rapeseed oil. There are low-erucic versions of rapeseed (sometimes known as Canola) that have been genetically modified to have a much higher level of Stearic acid (C18 saturated). High-erucic rapeseed is the most economic source, and its higher chain length provides greater lubricity in cosmetic skin creams.

There are, of course, Omega 5, 7, and 10, but they are found in much smaller quantities.

The marketing position for this in cosmetics is to demonstrate a balance of Omega 3, 6, and 9, using the above information by blending oils for specific applications. Although the base oils are far more important in topical applications, you can say that the product uses a balance of Omega 3, 6, and 9.

In nutrition, however, the level of the Omega fatty acids becomes very important from a claim point of view.

 

Need More Information?

I hope this explains this interesting aspect of fatty oils. If you’re looking to formulate with Omega rich oils in your next formulation, get in touch with the technical team at HARKE UK & Ireland for more information and to discuss product samples.