Ever since the term “natural skin care” started trending, it’s largely been used as a catch-all for products made from plants. It’s also a term that’s subtly suggestive of superior health benefits: As the clean beauty industry narrative goes, botanically based skin care is said to be better for us, because it’s less likely to contain chemicals that are thought to be unsafe for human health. In some cases, this may be true; however, not only are the terms “clean” and “natural” completely unregulated by the FDA—after all, any brand with a few drops of essential oils in its otherwise synthetic formula can slap the term on label, rendering the word near-meaningless—but it’s also incorrect to assume that earth-derived ingredients are more compatible with our skin than actives developed in a lab.

“There are many plants found in nature that have a wonderful affinity for the skin and provide nourishing and healing properties for it,” says skin-care formulator Leigh Winters Silberstein. “However, not all plants, herbs, and natural wonders of the world are good for you and your skin.” Winters Silberstein uses poison ivy as an example. It’s “natural,” sure, but there’s no arguing that it would make a pretty nasty addition to your daily moisturizer.

It’s also important to point out that most “natural” ingredients are highly processed before they make it into a serum bottle, blurring the line between natural and synthetic ingredients far beyond what you might think at first glance. Take zinc oxide, a sunscreen active that’s considered “natural” in most beauty circles, for example.  “Zinc oxide is found in the earth, but it’s contaminated with tons and tons of toxic chemicals,” explains Michelle Wong, PhD, medicinal chemist and founder of Lab Muffin. “To make the zinc oxide safe for use, a lot of the time, it has to get heated up to thousands of degrees Celsius to break it down and turn it into zinc metal, which is a chemical reaction. Then, it gets re-reacted with oxygen in the air to form zinc oxide again. This is a massive transformation that’s incredibly unnatural, but it’s considered a natural product.” To be clear, zinc oxide isn’t any less safe because it’s highly processed—as Wong points out, all that processing actually makes it better for us in the end.

So if we can’t rely on the simplistic “plants are good, synthetics are sketchy” model of vetting skin care products, what’s the best way to determine which ingredients are going to be the most effective? One approach is to seek out rigorously researched skin-care actives that are truly “natural” for skin—compounds that inherently live in our cells and unquestionably contribute to a healthy complexion. While many of these ingredients do come from a lab, plenty of plant-based heroes make the cut as well. “Don’t count nature out,” says Winters Silberstein. “Nature has a lot of answers that a lab never will, and vice versa.”

What’s “natural” for our skin, really?

Water and lipids are two key elements that naturally make up our skin’s barrier—the uppermost layer that protects the skin from environmental stressors and prevents dehydration. With that in mind, it makes sense that so many dermatologist-recommended skin-care products are formulated with this power duo. “Without properly caring for the skin barrier, our skin ceases to function optimally, leading to dryness, inflammation, and other skin woes,” says Winters Silberstein.

It’s easy to tell when a product contains water—it’s listed as such on the label—but lipid-promoting ingredients can have many other names. “Linoleic acid, or vitamin F, plays a key role in the synthesis of barrier lipids. It’s an essential fatty acid that’s essential for human health but not synthesized by the body,” Winters Silberstein explains. “Other lipids that contribute to epidermal health are ceramides and cholesterol, which are notable for water-binding properties and can be found in squalane oil.” Ceramides are commonly found in rich moisturizers, and these days, cholesterol is becoming more of a label star as well.

Deeper within the skin, you’ll find amino acids, peptides, collagen, and elastin, says dermatopathologist Gretchen Frieling, MD. These elements all help keep skin looking youthful and plump, and applying them topically can help to bolster natural supplies within. Wong adds that skin also naturally contains hyaluronic acid (in its lower layers), glycerin, and vitamins such as B3, C, and E. “When we use [these ingredients] in a product, we flood our skin with way more than is naturally there,” she says. “That’s the reason it has such a big effect.”

You still have to do some legwork to find out what will be compatible with your skin. “A product can say it has amino acids and collagen in it, but what percent of the product has it and how pure is it? This will depend on the quality of the products from the manufacturer,” explains Dr. Frieling. If this seems overwhelming, don’t fret: Search resources like Reddit or stick with derm-backed brands, which you can find both in their offices and at the drugstore.

Are synthetics or natural ingredients better for skin?

From a purely scientific perspective, experts agree that our skin can’t tell the difference between, say, vitamin C that comes from a plant and vitamin C that comes from a lab. “Trendy ingredients in skin care, like L-ascorbic acid and encapsulated retinol, are often synthesized in the lab, but they are biomimetic in design and therefore well-received by the skin,” says Winters Silberstein (biomimetic means they mimic skin composition). That said, not every skin-care ingredient has been rigorously tested to confirm its compatibility with skin. “There are a lot of data gaps with what your skin will actually recognize,” says Wong, who’s skeptical about the idea that skin-identical ingredients are actually better than those that aren’t inherently found in skin. “Your skin works pretty well, but theoretically we can always make it work better. Your skin’s natural oils, for example, aren’t that great for you—sebum is comedogenic, [which means] it clogs up your pores.”

Chemistry aside, there are a few other things to consider in the natural-versus-synthetic debate. “Pure naturalists argue that plants contain a living energy, and naturally sourced ingredients will always contain a more powerful cellular vibration than a lab-synthesized equivalent,” says Winters Silberstein. However, research shows that it may not have any basis in science, she adds, as analytical tests measuring energy output aren’t able to tell the difference between synthetic and natural compounds.

There’s also an environmental argument to think about, as using large quantities of natural materials isn’t always the most sustainable or ethical way to make a skin-care product. Winters Silberstein uses squalane as an example. “Squalane is a mega-moisturizing molecule that’s everywhere you look in skin care. Previously, you could only obtain it from a shark’s liver. Nowadays, squalane can be developed ethically and sustainably from sugarcane… a renewable resource that’s safe, vegan, and cruelty-free.”

Bottom line: Don’t be afraid of skin-care ingredients just because they aren’t “natural”

Dr. Frieling believes that there’s a place for both plant-based and synthetic ingredients in skin care—one isn’t inherently better than the other. “They can be used to complement each other,” she says. “With botanicals, these key bio-molecules have been chosen for the impact on improving skin cell function, reversing cellular aging, and creating a healthy skin environment. They have anti-aging properties that help calm and firm the skin, they’re an ideal addition for soothing sensitive skin, and they can help clear acne and can reduce itching and dryness as a result of eczema.”

In the future, Winters Silberstein  hopes to see nature and science come together more closely, creating a wider range of safe, biomimetic products that work with the natural make-up of skin. “I believe brands will start to look at how ingredients work more synergistically—from enzymes to vitamins—and find the balance that works for their mission, consumers, and the world.” In other words, it’s time to reframe the meaning of the word “natural,” once and for all.

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