It's estimated that about a third of all cosmetics-related skin reactions are related to fragrances (natural or synthetic).
But what exactly do the fragrances do to harm the skin?
The disappointing answer is: the science doesn’t fully understand why. It might have something to do with the fact that all fragrances used in skincare are volatile organic compounds (VOCs). But this chemical “family” is very broad and includes many different chemicals ranging from compounds that our own skin emits, to those causing strawberries or a face cream to smell delicious to road traffic pollutants.
In recent years, more research is being done on the possible mechanisms of skin sensitization for different classes of cosmetic fragrances, for example terpenes (linalool, citronellol, limonene, camphor) and benzene derivatives (vanillin, anisole, eugenol). In general, after a series of chemical reactions, fragrant compounds find a way to bond with our skin proteins setting off an alarm for our immune system.
Skin allergic and irritant reactions are different, but they seem related. Both involve an immune response, and, if a compound is known to cause skin allergy, it is likely to be a skin irritant as well. This is definitely the case with fragrances & essential oils. Hopefully, with more research underway, we’ll understand this issue better in a near future.
The distinction between skin allergy and irritation is useful to keep in mind, because while allergies tend show up with acute symptoms (like redness, itching, scaling), skin irritation might have very mild symptoms and can be harder to notice. This condition is called chronic or cumulative contact dermatitis (a medical term for skin irritation). It can show simply as skin dryness or slight redness, but beneath the surface, and inflammation might be going on.
And inflammation is not good for our skin at all: it can trigger acne, compromise our skin barrier, and increase collagen destruction. In short, it is the opposite of what we want our skincare to do.
Interesting fact: studies find that skin allergies and irritations are way more frequently caused by fragrances in skincare rather than in perfume. It’s likely that a combination of other compounds in skincare (like surfactants and preservatives) with fragrances is to blame.
We've talked about the risks, but how about an upside? There isn't one really - apart from indulging our senses. Fragrances, natural or synthetic, do not have any proven benefits for our skin.
In a nutshell, fragrances in skincare carry lots of risks, but don't offer any benefits. That's why I choose to avoid fragrance in skincare (natural and synthetic) as much as possible. What's your opinion?