Oleic acid

Rimshah

I have read oleic acid is detrimental to the skin barrier. I went through a study which showed olive oil is also bad as it includes oleic acid. As far as I know, oleic acid is converted to triglyceride. So I assume only free oleic acids present in oil may harm tha skin. Good quality olive oil has very low amount of free oleic acid, less than 0.8% in 100g extra virgin oil. What's your opinion? Do you have evidences which show oils high in oleic acid are bad for skin?

I have also read proper oleic to linoleic ratio of oil should be used in skincare i.e. small amount of oleic acid to high amount of linoleic acid (as it is beneficial for the skin). Do you know what ratio is that?

As linoleic acid is also not present in oils, oils high in linoleic acid are beneficial to the skin? 

MarkBroussard

Actually, Olive Oil is up to 80% Oleic Acid which is its main component, so I think you missed a decimal point there.

There isn't a specific ratio that I am aware of that is optimal, but the oils with a high Linoleic/low Oleic acid ratio include Sunflower, Safflower, Grape Seed Oil, Melon Oil, Prickly Pear Oil, Rose Hip Oil.  You will also notice that oils with a high Linoleic/low Oleic acid ratio absorb rapidly into the skin, whereas oils high in Oleic acid are "heavy", absorb slowly and leave a greasy feeling.

Oleic acid is commonly used as a penetration enhancer for pharmaceuticals. 

Pharma

@MarkBroussard: He is talking about free fatty acids, not total content .

Click HERE: A literature review (one of the few I could find) wherein they conclude that high oleic acid oils (triglyceride bound fatty acids) tend to cause skin irritation more than other oils do. Why, I don't know. It might have something to do with arachidonic acid metabolism (=inflammatory immune responses). BTW these days, sunflower oil comes from high or low oleic acid chemovars (fortunately, the label usually tells if it's derived from a high oleic acid cultivar).

@Rimshah: All free fatty acids have the tendency to irritate skin. As mentioned above, it's AFAIK about total oleic acid content, not just free oleic acid.

ngarayeva001

They all get rancid too quickly. Oleic slower than linoleic but if you want a stable product use synthetics and mineral oil. Butters are okeish because they are comprised of saturated fats mostly. I tried to find studies proving that veg oils have skin benefits but couldn’t find anything reasonable. 

MarkBroussard

Here's the quote from the article, which only addresses total oleic acid:

"Oils with the lowest oleic acid content provide a lower risk of irritant contact dermatitis."

Rimshah

To conclude, oleic acid oils should be completely avoided or use very minimal amount with high amount of linoleic acid oils in skincare products. 

Thank you all for sharing your knowledge.