Pipette

Baby Oil (2021)

As for linoleic acid and the skin, LA is a really important little guy found naturally in our skin. It is the most abundant fatty acid in the epidermis and it serves as a structural precursor for important skin lipids called ceramides. Knowing this, it will not come as a surprise that Linoleic acid has a central role in the structure and function of stratum corneum permeability, aka healthy skin barrier.  LA deficiency leads to an impaired more permeable skin barrier and the topical application of LA-rich sunflower oil can fix this issue rapidly (while oleic-rich olive oil did not have the same barrier repairing effect).

LA is not only important for dry, barrier damaged skin types but also for acne-prone skin. Research shows that problem skin has lower levels of linoleic acid (and higher levels of oleic acid) than normal skin. So LA-deficiency in the skin seems to be connected not only to an impaired skin barrier but also to acne and smearing LA all over your face might help with your problem skin. A double-blind study using a 2.5% LA gel for 4 weeks found a 25% reduction in the size of microcomedones, the tiny blocked pores that can later lead to acne.

If that was not enough, we have one more thing to report about LA.  It lightens hyperpigmentation (aka UVB caused sun spots) both by blocking the melanin production of melanocytes (the skin cells that make the pigment melanin) and by enhancing the desquamation of melanin pigment from the upper layers of the skin.

Overall, linoleic acid is a multi-functional skin goodie with barrier repairing, acne-reducing, and skin-lightening magic abilities. It's a nice one to spot on the ingredient list pretty much for any skin type. 

Maybe this thickness is the reason that Oleic acid is considered comedogenic, and if you have acne-prone skin avoid OA-rich plant oils, and choose linoleic acid-rich versions instead.

The thickness of OA also means that OA-rich oils are considered more nourishing and moisturizing than their LA-rich counterparts, and are generally considered to be more suitable for dry, mature skin types. 

As for oleic acid in its free form (and by free we mean that it is not bound up in a triglyceride structure like it is in oils), it mostly serves as an emulsifier or emulsion stabilizer in small amounts in regular cosmetic products. It is also quite well researched and is used in the pharmaceutical industry as a penetration enhancer. 

Leafy green vegetables, walnuts, flax seeds and fish oils are rich sources of ALA and if you are not eating a lot from these, supplementing with fish oil is a pretty good idea backed by research. It is a good idea both in terms of general health benefits as well as potentially improving inflammation-related skin issues such as atopic dermatitis or acne.

As for using ALA topically, we have to say that its role and effects seem to be less direct than with LA. ALA's main role in the skin appears to be modulating the immune response of the epidermis. This is probably helpful for inflammatory skin diseases but most studies examine ALA as an oral supplement and not when applied topically. One exception, we could find, is a study that found that topically applied ALA has nice spot-fading abilities.

To be honest, it seems to us that oral supplementation of ALA is more important than smearing it all over your face. However, that is not to say that topical ALA is a bad thing, it is a good thing. It is a skin-identical ingredient, it is probably moisturizing and anti-inflammatory but its topical effects are less established than that of fellow omega fatty acid, linoleic acid.