A Facial Oil Is Not a Serum: A Facial Oil Is a Facial Oil.
What do oil and water have in common? Well, not much. But many skincare brands are calling them the same thing. While they're both important ingredients in skincare, oil and water serve very different purposes and really don't fall into the same category. I'm talking about serums in this instance, or rather, facial oils that are being touted as serums.
Serums are primarily water based (serum in latin literally means "watery fluid"), and they can penetrate deeper into the skin because they are comprised of smaller molecules. Serums are usually considered the "active" or "treatment" step of your skincare routine because again, they have that ability to sink deeper into the skin, thereby initiating the most change. Common types of serums include Vitamin C and other antioxidant serums, peptide serums, serums with skin-brightening acids, retinol serums, and growth factor serums.
A facial oil, on the other hand, is oil based. Oils act as an occlusive, meaning they create a protective layer on the skin. They don't really sink in, and are generally used more to lock water based products (i.e. ACTUAL serums) into the skin. So while oil can provide a protective and possibly nourishing layer on the skin, it is not at all "active" like a serum- it just doesn't have the same penetration ability as a water based serum because oil is a larger molecule than water. (Now of course, there are exceptions to every rule, and there are lipid based products out there that contain active ingredients, but here I'm speaking of simple plant oils labeled as fancy serums- which is just plain false advertising).
Now that we begin to see how different an oil and a water based serum are, and the different purposes they serve, it seems a bit odd to let one pass as the other. I don't call my cleanser a moisturizer nor do I call my cat a dog (well sometimes I do, and that's a good example of wishful thinking). It's like calling two buck chuck a fine vintage. Or an intern a CEO. You have part of the component. You're kind of there. But you're also not there at all. Can you imagine if you called an Uber to take you to the airport, and a pedi cab showed up?! Would you get in?
So why are skincare brands likening oil to water, as if it's all just fine and good? To be blatantly honest, probably to sell you their product. I mean, serum DOES sound more potent and active than simply "oil," doesn't it? I'm not saying don't buy a facial oil labeled as a serum, but I am saying understand that's what you're buying. It could very well be a lovely product, even if it is wearing a disguise. Just don't fall victim to the allure of celebrity brands, rave reviews, magazine publicity, and cult followings that can make any infused grapeseed oil suddenly worthy of a $185 price tag. It's still an oil.
Just in case I've made oil out to be the Cinderella in the skincare lineup, I want to point out that I truly enjoy a facial oil now and then. It's more of an experiential thing for me- they are usually beautifully scented with herbal extracts and essential oils. I may use it to create a little ritual with some facial massage and gua sha- a completely wonderful and grounding sensory experience. In some cases of acne or compromised skin, switching to a bare bones routine using not much more than a facial oil, for a time, can be a great reset. But in terms of real, targeted results, I place my expectations in the serum category.
So how do we determine what is a worthy product and what is just marketing hype? Unfortunately it's pretty much up to the consumer to navigate these products with false titles. For starters, read the ingredient label! If the first ingredient of a serum is water (or aqua/eau), it is a water based serum. If the first ingredient of a serum is a plant oil, followed by more plant oils (usually with the Latin name included), it is an oil based serum. Some serums are a mix of both, using an emulsifier to hold water and oil together, so this is not a hard and fast rule. But in general, the first couple ingredients will paint a pretty good picture of what you're looking at. Second, consider the price. Compare it to the first few ingredients you see on the label. Does it add up? Does grapeseed oil cost $185 an ounce, or is someone selling you a fantasy?