Every Question You’ve Ever Had About The Skin Barrier, Answered

A few years ago, at least half of the beauty videos on your TikTok FYP included creators applying some sort of dramatic-looking at-home peel, declaring, beauty is pain! However, recently, there’s been a shift in how TikTokers are approaching skin care: The focus has gone from harsh exfoliators promising instant results like a baby smooth, radiant complexion, to slow, gentle products that focus on the moisture barrier and long-term skin health. This evolution of TikTok skin care advice is all in the name of "strengthening the skin barrier," which you've probably heard your favorite creators say once (or twice) in their videos.

The shift is happening offline, too. A number of skin care brands are launching products with “skin barrier” in their names. With the influx of launches and creator videos, it begs the question: Is the focus on the moisture barrier a passing TikTok fad like dozens of others before it? (See armpit masks.) Or, is it a long-term change in how the skin is viewed as a whole? To find out, TZR chatted with two dermatologists to properly explain the function of the moisture barrier, how it relates to the skin barrier, and the best barrier-health products to try.

What’s The Difference Between The Skin Barrier & The Moisture Barrier?

Brands and customers both use these terms interchangeably, so what’s the exact difference between the skin barrier and the moisture barrier? It turns out, it’s mostly just semantics, as the moisture barrier helps insulate the skin barrier. “The skin comprises five layers. The moisture barrier is the outermost layer,” says Dr. Aanand N. Geria, MD, FAAD, a board-certified dermatologist in Rutherford, NJ. This protects your skin’s natural oils, nutrients, and moisture. “The moisture barrier is key for insulating skin and avoiding harmful bacteria, environmental stressors, and other irritants.”

Dr. Lindsey Zubritsky, MD, FAAD, a board-certified dermatologist in Ocean Springs, MS, who recently spoke at Glow Recipe’s summit on skin barrier health in LA, says to think of the moisture barrier as the brick and mortar of the skin. “The skin cells are the bricks and the mortar is the ceramides and the glue,” she says. “The moisture barrier is referring to the ceramides and the glue part of the skin barrier.”

Why Is The Skin Barrier So Important?

Think of your skin barrier (and the moisture barrier along with it) as the first defense against skin damage, both long-term and immediate. “The skin barrier protects from external threats such as chemicals, infectious agents, system toxicity, and allergens,” Dr. Geria says. “It helps maintain homeostasis and prevents the body from losing water and dehydrating.”

Without this barrier, there would be no way to keep skin healthy — and healthy skin keeps moisture in and pollutants out.

How Is The Microbiome Related To The Skin Barrier?

“Microbiome” is another buzzy word you’ve probably seen pop up in skin care — and there’s a good reason for that. “On top of the skin barrier lives the microbiome, which is the good bacteria and the bad bacteria, and they all live in homeostasis in this balance,” Dr. Zubritsky says, “When that balance is thrown off, that's when your skin barrier can get damaged, because those feed off of each other.”

In short, when you have a microbiome that is out of balance, the skin barrier is damaged. (More on that in a second.)

What Causes Damage To The Skin Barrier?

It seems like once TikTokers understood the function the skin barrier — and the damage it can prevent — they started to treat it better. “[Peels and harsh exfoliators] may promise that they’re going to help your discoloration and fine lines and wrinkles, but in that process, you are creating more damage to your skin and causing more wrinkles and discoloration because of how aggressive those things are,” Dr Zubritsky says.

In addition to over-exfoliating, over-cleansing can cause a damaged moisture barrier because it’s removing the natural oils and good bacteria on the microbiome. There’s also “products that contain harsh ingredients such as baking soda, alcohol, and fragrances,” Dr. Geria says. In addition to harsh products, genetics, age, and environmental aggressors such as sun exposure and pollution are common causes of moisture barrier damage, many of which are out of our control. Dr Zubritsky is quick to add that smoking and vaping can be determental to the barrier, too.

What Are The Symptoms Of A Damaged Skin Barrier?

If you jumped on the “peeling solution” trend, chances are you know what a damaged skin barrier feels like — and it’s not great. Skin is overly sensitized, causing even gentle skin care formulas to burn on application. It could be dry, red, and you might even see acne pop up, whether you’re usually prone to it or not. “If you're having bad [acne] flare ups and you can't get under control, it could be because your skin barrier is damaged,” Dr Zubritsky says.

However, if you’re experiencing these symptoms it is possible to correct and avoid this scenario all together.

How To Protect The Skin Barrier

The silver lining is that you can protect the skin barrier from natural causes of damage. This includes wearing sunscreen every day, washing your face with a gentle cleanser, and applying a good moisturizer. If you have oily or acne-prone skin, look for lightweight and gel-based hydrators that won’t clog pores.

In addition, there are certain ingredients that strengthen the skin barrier, which have been popping up in all of these new moisturizers, cleansers, and serums. Look for: humectants such as glycerin and hyaluronic acid, which bind to water and retain moisture; emollients like rosehip seed oil and petrolatum to prevent water loss; antioxidants such as vitamins C, E, and B3 to neutralize free radicals; and ceramides that help seal in moisture.

The final verdict? Dermatologists agree: The skin/moisture barrier trend isn’t going anywhere. And that’s a good thing. “I don't understand how something like this should or would ever go away because it's just improving your skin health, which is, at the end of the day, what we all want,” Dr. Zubritsky says. “It's all about just repairing and focusing on what we have and not adding unnecessary things.”

Dr. Geria has seen this “less is more” trend gain speed during the COVID-19 lockdowns. “People tended to their skin at home, and being overzealous, many damaged their barriers by using too many products or acids that were too strong for their skin,” he says. “As a result, there are endless videos [on TikTok] on how to heal a damaged skin barrier.” He notes that our skin hasn’t changed but products have, with higher levels of active ingredients.

Now, as a result, the tide is just starting to turn. “Consumers are seeking products that are not a quick fix but maintain long-term skin health without stripping sensitive skin,” he adds.

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