Omega 3 and 6 fatty acids in skin care

Part of my job as a consultant chemist to the cosmetics industry is to evaluate existing research using a sort of SWOT analysis before suggesting a course action stemming from that.

Past examples have been as follows:

• What is the issue with palm oil and how best to tackle that?
• Can zinc oxide nanoparticles penetrate the skin and if so what damage could they do?
• Shea butter lip balms tend to develop grains on standing.  How big a problem is this and can it be prevented?
• What is a Halal cosmetic and what (if any) problems would they solve/ benefits would they bring to the market both as a whole and for the Muslim community.

Anyway, this week my topic is Omega 3 and 6 fatty acids and more specifically their alleged toxicity.  

Sunflower oil is rich in Omega 6 fatty acid. While we should take care not to eat too much Omega 6, slapping it onto our skin is actually quite good for us. Lovely job!

One of my clients has become concerned over information published about the toxicity of seed oils. More specifically this research focuses on the  large percentage of unsaturated fatty acids in oils such as Sunflower and almond.   The concern is that the oxidation of these oils on the face (which is exposed to both UV light, oxygen and moisture) would cause a degradation of the oils leading to cell damage, inflammation and the like brought on by the breakdown of these unstable fatty components.

When I initially got the call to look into this I thought ‘aha, yet another thing for us all to become paranoid about – as if there isn’t enough rope out there already’  but then I started to un-pick the question a bit further.

As with many simple propositions, the devil is in the detail and there is so much detail in here you would probably die of boredom or confusion before I got to the bottom of it.  So for those who are either a) on a short lunch break or b) have reading fatigue my quick conclusions  are as follows:

1. There is mounting evidence in nutrition/ dietary circles that we have it all wrong when it comes to fat.  Saturated fat is not all bad and unsaturated fat is not at all good.  That is why coconut oil is starting to be seen as a ‘cure all’ and is flying off the shelf where once it was overlooked in favour of canola.   This sort of thinking is also moving people away from margarine and other manufactured spreads and back to butter.  It is very interesting and something that based on what I have read is sensible but this blog isn’t really the place to dish out nutritional advice.  For those interested in that I’d look up the Paleo diet (which is the way I eat).  However, while this rationale seems to work well for the inside of our body, there is next to no evidence that I can find that the topical application of unsaturated (vegetable) oils is a concern.  On the contrary, there is much information out there outlining the health benefits.
2. Saturation vs Unsaturation  and all that jazz.   Yet again this question highlights to me just how confusing chemistry is for most people and how ill-equip the general public are to assess the risks of one ingredient against another.  That isn’t meant to sound condescending, it is what it is – Degree level organic chemistry and then some.  I did the course and found it interesting but blooming tricky.   Basically predicting oxidative stability isn’t as easy as just saying ‘well that one has lots of C18:2 (Linoleic acid which is an Omega 6) and therefore it is going to oxidize very quickly.   It would be nice if things were that predictable but in reality assessing oxidative stability of an oil requires consideration of the rest of the oil chemistry including the presence of longer and shorter fatty acid chains,  presence and types of antioxidants, process method, plant quality and packaging.
3. Oxidation on my face!!!!  OK so this one is something that I did start to wonder about as the theory seemed to have a point. However, what I found was this. These omega fatty acids are important components of our skin barrier and can greatly improve the look and feel of our epidermis.  To do work in cells they need to be oxidised or else they can’t be utilised.  Now, I’m not saying that the sun, oxygen or water oxidises them in all the right ways (as the oxidation cascade is also capable of being complex) but maybe, just maybe this works for good rather than evil.
4. Oxidation in the pack.  The industry that has carried out lots of research into stabilising omega fatty acids in a product situation is food.  I have read a number of studies who conclude that the act of forming a stable homogenous emulsion where the fatty acids are in the dispersed (or internal phase) stabilise the acids and prevent oxidation.  This translates well to cosmetics and on the surface would seem that a cream, lotion or balm is better able to deliver the benefits of these Omega rich oils than say an oil-only blend which would require a much higher percentage of antioxidants to stabilise.
5. In-use evidence.  Study after study that I uncovered while researching this pointed to there being positive benefits to using omega fatty acids on the skin in terms of barrier functioning, appearance, cessation of itching and moisture content.  Personally I know of studies where Omega rich oils have boosted SPF of a product (don’t get too excited, we are talking 1-4 points only) and other studies that have used them to reduce erythema, heel scaring and boost elasticity of scar tissue (Rose hip oil anyone?)

Basically I have come to the conclusion that while these unsaturated oils can and do degrade over time, this should not be a major cause for concern on the skin in terms of adding to rather than alleviating visible signs of ageing.   The thing that makes these seed oils attractive in skin care is their antioxidant potential, the essential fatty acid content and their phytochemicals.  Unfortunately this up side has a down side being that they will turn rancid quicker than saturated fats.  However, if handled and stored correctly that can be kept to a minimum.  Also if you are worried I’d apply your active oils either at night, or a good hour before you go out into the sunlight just to give them time to sink in.  In addition you can also apply sunscreen over the top or wear a hat.

Lots of options but one option I don’t subscribe to is avoiding these oils!

I have uncovered LOTS of info on this topic so might expand on some of those five points in further posts.

Amanda x