Washing Your Face Could Disrupt The Skin Barrier? Here Is Why.

Updated on: 22 June 2021

Washing your face is a daily routine that you tend not to overthink. But do you know that it is actually one of the harshest steps in a skincare routine and could disrupt the skin's barrier?

To understand why we must first understand the science behind how cleansers work to clean your face and why you even need to wash your face every day.

Why do you need to wash your face everyday in the first place? 

We are exposed to various environmental factors every day such as dirts, pathogen, pollutants, and UV radiation. 

At the end of the day, your skin will be full of these daily grimes  and need to be cleaned.

Excess sebum, dirts, makeups, and sunscreen residue can clog pores if left uncleaned.

Environmental air pollutants such as polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), oxides, particulate matter (PM), ozone (O3), and cigarrette smoke, are associated with skin aging, sensitization, acne, and even increased sebum production¹.

Some of these daily grimes are water-soluble and can be cleaned with water, but some are not. Hence, washing with water alone is not enough and why you need cleansers. 

Why cleaning with water alone is not enough? 

As you might recall from your chemistry class, water and oil do not mix. Hence, water can't clean non-water-soluble grimes (oily substances such as sebum) effectively. Try washing grease only with water, and you won't have much luck.

There are two ways to clean oily grimes, either with solvents or surfactants.

Solvents are substances that can dissolve other substances, and one of the chemistry principles that you might have heard is like-dissolves-like.

Thus, to clean oily grimes, you need oil-soluble solvents, such as plant-derived oils or alcohols.

Cleansing oil and balms, the one that you typically used as the first step of your double cleanse routine, work based on this principle.

Another way to clean oily grimes is with surfactants, and most cleansers available today rely on surfactants.

What on earth are surfactants?

Surfactants are molecules that have different solubility properties for their head and tail parts.

The head is hydrophilic, which means it is attracted to and soluble in water. The tail is lipophilic, which means it is attracted to and soluble in lipids and oils (the opposite of hydrophilic).

Given surfactants' amphiphilic properties, they are beneficial for many applications. For example, surfactants can be used as cleansing agents, foaming agents, emulsifiers, solubilizers, and many other things.

How do surfactants work to clean dirt?
In water, surfactants group together to form micelles if there is enough concentration (a point called the critical micelle concentration).

When micelles are formed, the tail "sticks" with the grimes, and the head "sticks" with water. The formation enables water to wash away the non-water-soluble grimes.

How could cleaning your face disrupt the skin's barrier then?

The skin's barrier, a.k.a. the stratum corneum, is a waterproof barrier that forms the outermost layer of your skin.

The skin's barrier has several essential functions: (1) Keep our skin hydrated by minimizing transepidermal water loss (TEWL); (2) Protect us from external assaults from the environment such as dirt, microorganism, irritant, and pollutant; (3) Protect us from damaging UV ray.

It is made of a bunch of protein (70% by weight), water (~15%), and lipids (~10%), arranged in a "brick and mortar" structure.

Some of these lipids, consisting of ceramide, cholesterol, fatty acids, and other lipids, are susceptible to removals by surfactants.

While surfactants are helpful to clean daily grimes, they could not distinguish your skin's natural oils from grimes.

Thus, every time you wash your face, some parts of your skin's natural oils are also stripped off.

This is why sometimes your skin feels dry, tight, and itchy after washing your face, especially if you are using cleansers with harsh surfactants.

If you let your skin dry out for an extended period, it could disrupt the skin barrier function.

Water content in the stratum corneum is an essential part of the skin's desquamation (skin renewal cycle) process.

If the water content drops below 20% for an extended period, the enzymes involved in desquamation will be unable to function, disrupting the cycle.

Orderly desquamation of the stratum corneum is essential and can lead to a self-renewing cycle of dry skin if disturbed².

Not all surfactants are created equal

Surfactants are a large class of ingredients. They have various uses in skincare, such as cleansing agents, foaming, thickening, solubilizer, and emulsifier. Their impact on the skin also varies.

For example, sodium lauryl sulfate, a.k.a. SLS, is a commonly used surfactant and effective cleansing agent. In fact, SLS is too good at cleansing to the point that it is harsh to the skin. It can be mildly irritating, dry out the skin, and disrupt the skin barrier's structure³. 

Luckily, there are also other surfactants that are relatively mild to the skin. One of the more popular ones is sodium laureth sulfate, a.k.a. SLES. 

SLES often got lumped together with SLS in a “free-from” claim by many skincare brands. It is unclear where the association came from initially, perhaps due to its similar-sounding name or the misconception that all sulfates are harsh to the skin.

In reality, even though SLES is produced similarly with SLS (plus the additional ethoxylation process), it is substantially milder to the skin. It can also be formulated with other co-surfactants such as cocamidopropyl betaine to make it even milder⁴.

SLES might not be the mildest surfactant out there, but it is acceptable for most people except perhaps for those with very sensitive skin.

Are there other surfactants that are gentler to the skin? Yes, here are some of the commonly used mild surfactants today:

• Betaines (e.g., cocamidopropyl / coco betaine): Medium strength cleansing agent but relatively mild to the skin. They are often combined with other surfactants to enhance its mildness.
• Isethionates (e.g., sodium cocoyl isethionate): A particularly mild surfactant backed by numerous research studies.
• Glucosides (e.g., coco / decyl / caprylyl glucosides): Mild cleansing agent with high foaming abilities. Plant-derived and biodegradable.
• Sarcosinates (e.g., sodium cocoyl / lauroyl sarcosinate): A particularly mild and biodegradable, amino acid-based surfactant. It has a good foaming ability and can improve the overall mildness of a formula.
• Glutamates (e.g., sodium cocoyl / lauroyl glutamate): Mild amino acid-based surfactants suitable for sensitive or baby skin.

This list is not exhaustive. There are other mild surfactants that are not mentioned here.

If you are unsure of any particular ingredients, you can always visit a reputable ingredient database website such as www.incidecoder.com to find out more about the ingredient.

Given all this information, what can you do to make washing less harsh to the skin?

1. Choose a mild facial cleanser regardless of your skin type.

Generally, you don't want the squeaky clean after-feel because it means the skin's natural oils are being stripped off excessively.

This could lead to dry skin (usually accompanied by itching and tight feeling) and a damaged skin barrier.

If you have oily or acne-prone skin, the squeakiness might give you a satisfactory clean feeling, but resist the temptation. Your skin can be clean without it feeling squeaky.

What if you wear waterproof makeup or sunscreen? Mild cleansers alone might not be enough to clean all the residue.

Consider adopting a double cleanse routine. Micellar waters, cleansing oils, and cleansing balms can remove waterproof makeups and sunscreens gently. Rinse with a mild cleanser afterward.

2. Try not to wash your face too often.

Try not to wash your face more than 2x a day, once in the morning and at night.

If you must wash your face mid-day, perhaps you sweat heavily in the gym, apply a moisturizer afterward.

An increasing number of people are washing their faces only with water in the morning and are reporting healthier and better-looking skin.

However, this might not be for everyone, especially if you have very oily skin and live in a hot and humid climate. Nevertheless, you can give it a try and see if it works for you.

3. Try not to wash your face with water that is too hot.

You probably know this already, but hot water cleans better than cold water.

The science behind why it is the case can be too long to discuss here, but a simple experiment of cleaning dirty dishes in the kitchen with hot and cold water should prove this point.

If you love your hot shower/bath (like me), apply a moisturizer afterward.

4. Follow up with a moisturizer.

Moisturizers are essential to replenish moisture back to your skin (with water and humectant) and keep it hydrated by forming an additional layer with emollients/occlusives to slow the process of transepidermal water loss (TEWL).

We have already discussed the importance of maintaining well-hydrated skin for the skin barrier above.

Sources

1. Drakaki, E., Dessinioti, C., & Antoniou, C. V. (2014). Air pollution and the skin. Frontiers in Environmental Science,
2. Draelos, Z. D. (Ed.). (2015). Cosmetic dermatology: products and procedures. John Wiley & Sons.
3, 4. Ananthapadmanabhan, K. P., Yang, L., Vincent, C., Tsaur, L., Vetro, K., Foy, V., ... & Subramanian, V. (2009). A novel technology in mild and moisturizing cleansing liquids. Quadrant, 22(6), 307-316.