Chemistry Lesson: Essences

The Zoe Report’s Chemistry Lesson is an ongoing series where leading cosmetic chemists break down the science behind how your favorite beauty products work. First up, experts explain everything you need to know about the moisturizing properties of essences — and why you should think about working them into your usual skincare routine, ASAP.

Oh, the irony of the term "essence." Most would hardly consider this under-the-radar skincare step an essential (save for the K-beauty diehards, of course). At least, not yet. There’s a lot of confusion in the skincare community about essences — are they cleansing waters? are they toners? — which is exactly why this chemistry lesson is now in session. If you're wondering how to add essences to you skincare routine, you've come to the right spot.

Essences are to skincare what primers are to makeup: They set the stage for flawless application and make the active ingredients in your subsequent skincare steps that much more effective. These products are typically made with ingredients that have small molecular values — i.e., they can penetrate deep within pores to prep the skin for what's coming next. On top of that, essences are known for delivering serious hydration. So that elusive, dewy glow you're always chasing? Yeah, you're gonna want an essence for that.

Ahead, your personal study guide to Essences 101.

The Basics

Even if you’re not familiar with the functionality of an essence, you’ve likely seen the term emblazoned on increasingly more products throughout Sephora, Ulta, and Amazon as of late. While these bottles do hold liquid formulas reminiscent of your favorite micellar waters and pH-balancing toners, don’t let that fool you: Essences belong in a category all their own.

“A toner is focused on balancing the skin’s pH, and a cleansing water is focused on removing impurities from the skin — but an essence is more focused on delivering moisture deep within skin,” Alicia Yoon, founder of skincare mecca Peach & Lily, tells The Zoe Report. And although this step may seem new to some — especially Americans — essences have been a staple of Asian beauty for years. “I remember essences from even a few decades ago growing up in Korea,” Yoon says. The product category began popping up in the United States when the K-beauty boom of 2011 hit (remember the influx of BB creams?), but never quite made it to the mainstream... until now, that is.

"Essences restore the natural moisture balance that has been altered during the cleansing and toning routine."

“These formulas are basically concentrated liquid moisturizers to be used after cleansing and toning,” Dr. Adarsh Vijay Mudgil, medical director of Mudgil Dermatology, tells TZR. Typically, an essence will contain either humectants or emollients (or both) — aka, ingredients that draw in water and soften the skin, respectively. "Water serves as a delivery vehicle for the ingredients that are [inside]," Ron Robinson, a cosmetic chemist and founder of BeautyStat.com, tells The Zoe Report. He explains that when you apply an essence, the water basically chauffeurs substances like glycerin and hyaluronic acid (humectants) or shea butter and squalane oil (emollients) down to the inner layers of the dermis. Then it evaporates, leaving the good stuff behind to do its job.

The basic benefits of using an essence are two-fold. “First, essences restore the natural moisture balance that has been altered during the cleansing and toning routine,” Dr. Art Rich, a cosmetic chemist, tells The Zoe Report. Secondly, “They prepare the skin for anything coming after,” Dr. Mudgil says. Because of their humectant or emollient content, these products give the pores a sponge-like quality, helping them better absorb the active ingredients in the products you apply afterwards.

Think about it this way: A dry sponge won’t collect as much liquid as a damp sponge will — those first few drops just roll right off the top. Since cleansers and toners tend to be stripping, they can leave the skin dry and tight; in other words, not the ideal canvas for serums and moisturizers. But by providing your skin with hydration via an essence before you move on to the next steps in your routine, you give your skin the ability to really soak up all that active ingredient goodness.

The Properties

“Essences typically contain potent humectants and emollients,” Dr. Mudgil says. He cites hyaluronic acid and glycerin as two essence ingredients to look for. As humectants, they function almost as magnets for water, drawing moisture into the skin and holding it there. Each humectant has its own unique benefits: Hyaluronic acid is known for carrying 1,000 times its weight in water and binding water to skin cells; while glycerin molecules are smaller and can penetrate deep within the skin, carrying water into the inner layers of the dermis for unmatched moisturization.

As far as emollients, “Butters like mango, shea, and cocoa are a plus,” Dr. Rich tells The Zoe Report. Lanolin, mineral oils, and squalane oil are also considered emollients, which work to lock in hydration by preventing a natural function of the skin known as TEWL — transepidermal water loss.

“First comes cleansing, then a toner, then an essence. Follow that with your serums, and then seal it all in with an eye cream and a moisturizer.”

But that’s not all essences have to offer. “Essences can be formulated for many different secondary benefits as well, such as brightening, firming, or calming skin,” Yoon says. To target specific concerns, Dr. Mudgil recommends seeking out essences that contain antioxidants like vitamins A, C, and E. In addition to protecting the skin from the damaging effects of environmental pollution, all three antioxidants offer extra skin-boosting benefits. Vitamin A is an anti-acne and anti-aging agent (it is, after all, the vitamin that gave the world retinol); vitamin C simultaneously brightens skin and promotes the production of collagen; and vitamin E softens and calms reactive or sensitive skin.

However, pay attention to the ingredients you’re mixing — as it turns out, too much of a good thing can actually be a very bad thing. “With a multifaceted face care program, care needs to be taken that certain product functions — like skin brightening or exfoliating — should not be provided by more than one formula,” Dr. Rich says. For example, if you already use a vitamin C serum, adding a vitamin C essence to your routine may cause issues. “There could be an ‘overdose’ type of reaction with redness, burning, or irritation,” the cosmetic chemist warns.

In general, Dr. Rich advises against essences that contain alcohol or exfoliating agents. Both can strip the skin and dry it out, thereby negating the whole point of using an essence in the first place.

Other than that, Dr. Mudgil maintains there are really no downsides to using an essence — it’s a practically risk-free skincare step.

The Formula

Now, the question you’ve all been wondering: Is an essence really necessary? For those with dry skin (which lacks oil) or dehydrated skin (which lacks moisture), the answer is a resounding yes. This crucial step renders every subsequent skincare product more effective, all while delivering much-needed hydration… and as Dr. Mudgil says, “You can really never be too moisturized.”

If you’re on the oily side, you may think that essences haven’t earned a coveted spot in your skincare lineup — but that’s not necessarily true. All skin types need proper moisturization; and what’s more than that, it’s totally possible for skin to be both oily and dehydrated. The telltale sign of dehydration for the oil-prone? If your face feels simultaneously stiff and greasy, like the oil is sitting on top of your skin instead of soaking in, you’re likely lacking hydration. An essence may be just what your skin needs to regulate, says Dr. Mudgil.

To incorporate an essence into your existing routine, Yoon has a no-fail approach to product layering. “First comes cleansing, then a toner, then an essence,” she says. “Follow that with your serums, and then seal it all in with an eye cream and a moisturizer.”

If you can’t fathom adding another step to your already-stacked skincare regimen, I get it — and so does Yoon. “To condense steps, you can use a toner-and-essence-in-one, like the May Coop Raw Sauce.” she says. Her brand’s Wild Dew Treatment Essence also boasts pH-balancing ingredients that can be used in lieu of your usual toner; and PhytoCELL Cell Moisture All in One Essence acts as a toner, essence, and lotion in one simple step.

With that, class is dismissed. Your homework? Experiment with essences — then just try and tell me it’s not a skincare essential.

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