I wish the plant alchemists who coined the term “essential oil” in the Middle Ages would've paused to consider just how much confusion they'd cause for future skincare enthusiasts. Back then, “essential” meant “of the essence” — and therefore, an essential oil was one extracted from a pure, whole plant. But in this century, “essential” is most often used as a marketing term; as in, “This face oil is essential to your routine.” Nope, not the same thing. In an effort to clear the confusion around regular oils vs. essential oils, I went straight to the experts: dermatologists, aromatherapists, and cosmetic chemists.
“Essential oils are a concentrated mixture of natural, volatile, and aromatic compounds obtained from plant material — flowers, buds, seeds, leaves, twigs, bark, herbs, wood, fruit, and roots,” Suzanne LeRoux, the founder of One Love Organics (who also happens to be an aromatherapist and a cosmetic chemist), tells The Zoe Report. Essential oils are typically created by steam-distilling the entire plant into a concentrated liquid. “They also sometimes are made by cold-pressing the plant — think of peeling an orange and the little droplets that emerge when you bend the peel,” adds Shannon Davenport, the aromatherapist behind Esker Beauty, in an email to TZR. “With woodsy oils like frankincense, they dry the sap, also known as resin, and then steam that so it becomes a liquid.”
To make things even harder to understand, this concentrated liquid doesn’t usually feel like oil — essential oils are pretty watery, in fact. They don’t “sink” into the skin like face oils, either; instead, they evaporate quickly. “[It] makes me feel like 'essential oil' is a bit of a misnomer,” Davenport says. “I like to think of them as pure plant extracts.” She likens them to herbs and spices: “Basically, essential oils are the liquid form of a group of plants, and they vary wildly in usage, function, and characteristics — just like curry powder is super different from basil.”
In the same way you don’t consume a spice on its own, you don’t use an essential oil on its own, either. These extracts are potent, and need to be combined with a “carrier oil,” or a thicker oil that doesn’t evaporate easily, before use. “Essential oils are almost always diluted by mixing them into something,” Emily Voth, the founder of Indigo Wild, tells TZR. “They are called ‘carriers’ because they carry the essential oils onto the skin.” So, if skincare was soup (stick with me here) essential oils would be the spices and carrier oils would be the broth.
Carrier oils are also referred to as “plant oils” or even just “oils,” for short. “Plant oils are fats taken from plants — usually from plants’ seeds, nuts, or kernels,” LeRoux explains. “They generally contain components such as fat-soluble vitamins, minerals, antioxidants, and other nutrients that nourish the skin, so they are quite beneficial in their own right.”
They differ from essential oils in so many ways, but three of the biggest are fragrance, feel, and effect. “Carrier oils do not contain a concentrated aroma like essential oils — though some may have a mild distinctive smell, like fresh virgin organic coconut oil,” LeRoux says. “Carrier oils also have a more ‘fixed’ state, meaning that they stay on the skin while essential oils evaporate quite easily.” As such, all plant oils basically have one common goal: to support the skin’s barrier, which is (not coincidentally) made up of many of the same lipids found in plant oils. Essential oils, on the other hand, provide therapeutic benefits specific to each plant — and powerful therapeutic benefits at that, hence the need for dilution. “So you need a carrier oil to use an essential oil in most cases, but you do not need an essential oil to use a carrier oil,” LeRoux summarizes.
Examples of essential oils commonly used in the skincare space would be lavender, frankincense, rose geranium, bergamot, and tea tree. (All of which have aromatherapeutic benefits, too. Inhaling frankincense, for example, has been shown to ease anxiety.) “Tea tree oil, if properly diluted, can be helpful with acne,” Dr. Devika Icecreamwala, M.D., F.A.A.D., a dermatologist with Icecreamwala Dermatology, tells The Zoe Report. Popular carrier oils include almond oil, avocado oil, jojoba oil (although jojoba oil is technically a “wax ester” pressed from jojoba seeds), olive oil, castor oil, and rosehip oil.
Here’s where a lot of misinformation starts: Some plants, like rose, are used to produce both essential oils and carrier oils. Rose essential oil is distilled from the entire plant, while rosehip oil (a carrier oil) is pressed from rosehips, the fruit of the rose plant. How are you supposed to know which is which? If you’re not able to touch and smell each oil that piques your curiosity in person — essential oils will be watery and fragrant, carrier oils will be thick and mild — scan the product description for some keywords. “Reputable essential oil companies will say on the bottle ‘100 percent pure essential oil,’” Voth says. “If it doesn’t say that, it’s not an essential oil.” Another telltale sign? Essential oil bottles are typically tiny (you only need a drop or two at a time), and carrier oil bottles are bigger.
The final piece of confusion to clear up, then, is the safety of essential oils. There’s a lot of debate about their place in skincare: Some enthusiasts swear by them for everything from brightening hyperpigmentation (thanks, frankincense!) to killing acne-causing bacteria (that's all tea tree), while others warn against their potentially irritating effects. “I feel sad when I hear people say things like 'essential oils are known irritants,' because the same is true of so many amazing skincare ingredients — look at retinol,” Davenport says. “Retinol would be a disaster if we applied it to our skin in its pure form, but instead we understand that it needs to be a specific, very low concentration in order to do its job without damaging our skin.” Essential oils require the same thoughtful formulation and careful application.
“Over the past 20 years, I have experienced amazing beauty and skin benefits with the correct use of essential oils,” LeRoux says. “I think sensitivities to these oils pop up when the formulator is not experienced in using them, or choose ones that are great in aromatherapy but are not good for skincare, or buy products from manufacturers who do not know how to source, store, and carefully introduce essential oils into the production process.” For this reason, it’s probably best for beginners to buy pre-mixed products from reputable sources, rather than experiment with essential oil DIYs.
Ahead, 10 essential oil products — all properly diluted in carrier oils, of course — that are, ahem, essential to any skincare routine.