Natural oils have been used as topical skin and body care treatments for the skin for years – so what are the best oils than will benefit the skin? Many oils contain oleic acid and/or linoleic acid. Research indicates oils with a higher oleic acid content are NOT beneficial to an impaired skin barrier. Oleic acid (OA) can be used as a penetration enhancer so it increases the skins permeability, and it appears to act selectively on the extracellular lipids representing the principal regulatory channel for the penetration of small molecules. Even minute amounts of oleic acid are sufficient to cause local (i.e. inside the viable epidermis) modulation of cytokine production – therefore irritation to the skin.
The levels of OA in an oil can rise over time – it is part of the ‘going rancid’ process, that it can vary depending on how the oil is distilled and that it changes from season to season.
Jojoba oil is not being mentioned in this article since is falls under the wax category and is not considered an oil.
Sunflower seed oil is one oil that is rich in linoleic acid, and has been used topically in the treatment of essential fatty-acid deficiency, rapidly reversing the disease with its excellent transcutaneous absorption. Locally, these essential fatty acids can help maintain the skin barrier and decrease transepidermal water loss.
In skin care products, linoleic acid should be the most frequently used essential fatty acid as it prevents barrier and cornification disorders, plus it lowers the transepidermal water loss and increases skin moistness. Linoleic acid is part of the ceramide I which is the most important barrier substance in the horny layer. Products containing linoleic acid are the appropriate skin care for individuals suffering from neurodermatitis as their skin generally shows a ceramide I deficiency. The disadvantage of oils containing linoleic acid is the relatively limited shelf life as they are sensitive against atmospheric oxygen. Safflower oil for example has a considerably shorter shelf live than olive oil. Oils with a natural content of antioxidants like for example vitamin E have a substantially longer shelf life.
Additional Oils with over 50% Linoleic Acid (with their percentages Linoleic Acid) include: Passion Fruit Seed, Safflower Seed Oil (High Linoleic), Evening Primrose, Papaya Seed, Grape Seed, Chardonnay Grape, Wheat Germ, Black Seed, Soybean, Red Raspberry, Hemp Seed.
To conclude: since there are many different opinions, it is up to the esthetician to do due diligence in their research to find products that are beneficial to the skin.