Your skin barrier:
The facts

This guide provides you with essential insights into the mighty stratum corneum!

We'll cover what it is, why it is so important, signs it could be damaged, and all importantly how you can protect and repair it.

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What is the skin barrier?

The skin barrier (also called the stratum corneum) serves as the outermost protective layer of the skin.

This skin barrier is often described as like a brick wall. The skin’s cells are the ‘bricks’, made up of keratin (a protein) and natural moisturisers and the ‘mortar’ in between holds it together. In this analogy, the ‘mortar’ is made up of lipids containing essential nutrients that the skin needs to protect, hydrate and nourish the deeper layers of skin.

Dead skin cells are continually shed from the skin’s surface. This is balanced by the dividing cells in the basal cell layer (one of the layers of the epidermis) which is in a state of constant renewal.

Exposed to external elements as well as being connected to the body’s internal functions, the skin barrier can be a barometer for not just your skin’s health but also the detection of other issues that might be going on in the body.

Why is the skin barrier so important?

The short answer is that it’s an essential defensive shield. It’s a natural body armour designed to keep the body’s systems balanced. Four key functions of the skin barrier are:


The skin barrier acts as a first line of defence protecting the body from infection and harmful microbes.

This natural shield contains a network of specialised immune cells in the epidermis. These include cells called Langerhans cells whose job it is to keep guard. When these lookout cells detect foreign and potentially harmful substances, they activate the body’s immune system sending antibodies and other immune cells ready to fight infection.


The ‘brick wall’ structure of the stratum corneum is designed as a moisture-locking barrier system. If you have a strong skin barrier, it will retain water efficiently keeping your skin hydrated, smooth, and elastic.

When the skin barrier is healthy and hydrated, nutrients are easily carried to the skin cells via blood vessels and carrier proteins, maintaining the overall health of the skin. However, when the barrier is compromised, this balance is disrupted, causing problems.


The stratum corneum is the body’s first line of defence against damaging UV rays. It cleverly provides both a physical barrier against over exposure, as well as allowing some penetration of solar rays to allow the production of Vitamin D. Those rays which do penetrate the skin’s surface enable the production of the pigment melanin, which provides further protection. However, if the skin barrier is compromised, this finely tuned function is disrupted. It is therefore vital to protect the surface of the skin and maintain the integrity of the skin barrier function.


Pollution often contains free radicals - unstable molecules that can cause oxidative stress.

Free radicals are highly reactive molecules with unpaired electrons. In an attempt to stabilise themselves, they interact with other molecules in the skin, including lipids, proteins, and DNA. This process leads to oxidative stress, causing damage to these essential components.

A healthy skin barrier works to prevent pollutant particals directly reaching the living skin cells.

What do we mean by a compromised skin barrier?

The term compromised (or more simply put - damaged) skin barrier refers to a situation where the outermost layer of the skin, is weakened or impaired. This results in a disruption of the skin's protective functions and may manifest in various signs and symptoms (see section below for more details on this).

What are the signs that the skin barrier is damaged?

These symptoms are a warning sign for you to take action. Let's look at them each in more detail:


A breakout of acne and spots is a sure sign that your skin barrier is compromised. The skin’s self-protecting mechanisms have reduced which has made it vulnerable to infection.

It’s important to address the problem as these can ultimately cause scarring and hyperpigmentation.

Itchiness can be maddening and usually comes hand in hand with redness and/or flaky skin. This type of symptom is usually short-term and resolves itself when the skin barrier is back to normal.

If the itchiness persists then it may be down to an underlying condition such as eczema, other symptoms may appear which will need to be addressed.

Dry skin may be rough, scaly flaky and sometimes itchy and sore. It’s very common and may be caused by environmental factors, changes in your skincare routine or dehydration. Untreated, external aggravators can penetrate breaks in the barrier and increase the permeability of foreign and potentially harmful substances. This can lead to further damage to the deeper layers of skin.


Dehydrated skin occurs when there is a lack of water content in the skin. This disrupts the balance of the lipids in the stratum corneum.

The reduction in moisture weakens the integrity of the skin barrier, making it more susceptible to damage. As a result, the skin becomes more prone to irritation and sensitivity.


Uneven skin pigmentation, also known as hyperpigmentation, can arise from skin trauma, such as wounds, cuts, or aggressive cosmetic procedures. The healing process may involve inflammation and repair mechanisms that temporarily affect the skin barrier.


Redness of the skin may be caused by anything from sunburn to an allergic reaction. A compromised skin barrier can also be a precursor to skin disorders such as rosacea.

Blood also rushes to the skin’s surface, causing the redness, to fight off any irritants and encourage healing.

Key causes of skin barrier damage

There are multiple factors that can cause skin barrier damage. Knowing what they are will help you protect your skin.

Click on the + to expand each section and read more.

#1: Overwashing / over-exfoliation

It’s true, you can be too clean!

Skin continuously produces natural healthy oils which are vital to maintaining its balance and protective properties.

It’s important to keep skin clean and exfoliate regularly, however too much and too often disrupts the natural pH and strips the skin of these natural and important oils. This can lead to damage and breakouts of spots, dryness and rashes.

#2: Pollution

Environmental factors can be responsible for interrupting the skin’s natural protection system.

Dust from the air can clog pores and increase bacteria on the face, leading to spots and acne. Other pollutants in the air can break down the skin’s natural oils responsible for maintaining the moisture in the skin, resulting in dehydration, acne, hyperpigmentation and dermatitis.

#3: Genetics

How much does genetics affect the skin? Unfortunately, you can’t escape your genes! Genetics do influence the type of skin we have.

Genes also can be a predisposition to certain skin conditions including acne, eczema and even types of skin cancers such as melanoma. That’s not to say that you will inherit these conditions, it just means that you may be more prone to them.

#4: Ageing

There’s no escape, your skin changes with age. The skin becomes thinner, it loses fat and doesn’t look as plump and smooth as it was in the past. Gravity can cause the skin to sag and wrinkle as the skin becomes less elastic over time.

Even if fantastic genes have been passed down by parents, skin ageing can be intensified by an individual’s lifestyle choices.

#5: Lack of sleep

The body ideally needs 7 or more hours of sleep a night. Inadequate sleep can cause a dull complexion and other skin-related issues.

What causes this is the rising of the body’s cortisol levels when the body hasn’t had enough sleep. The high cortisol levels increase the skin’s sebaceous glands to produce more oil. This increased sebum (oil) can trigger inflammation which breaks down the proteins that are responsible for keeping the skin smooth and glowing, leaving the skin looking dull and vulnerable.

Increased oil production can also cause infection, putting the skin at risk of acne and allergic reactions.

Read more about the importance of sleep to your skin in our article here.

#6: Stress 

Unfortunately, stress can also play a role in compromising the health of the skin barrier.

As the body’s largest organ, it isn’t just external factors that are responsible for maintaining healthy skin. The skin can also reflect what’s happening inside your body.

Stress and anxiety, like lack of sleep, can cause raised cortisol levels resulting in increased inflammation. When under stress the sebaceous glands produce more oil which can cause acne and other outbreaks to worsen in those who are prone to outbreaks, whether eczema, psoriasis or other conditions.

#7: Cold weather 

It’s not just the sun that causes skin problems. Cold winter months can also compromise skin health.

The cold, wind, rain and icy conditions can strip the skin’s natural protective barrier. Once the barrier has been damaged, its natural defence is compromised which can trigger conditions such as dry skin (xerosis) and eczema.

Sudden temperature changes can also stress our body and challenge our immune system so a sudden cold snap often results in skin problems because the body’s state of equilibrium is abruptly altered.

How can I protect my skin barrier?

Although the stratum corneum is the first line of defence in keeping body systems balanced, it isn’t infallible. There are proactive decisions that can be taken to protect the skin barrier and ensure that it doesn’t get easily compromised:

  • Avoid excessive heat or extreme cold
  • Don’t use harsh cleansers or aggressive exfoliants
  • Use a broad-spectrum SPF
  • Drink plenty of water & eat water-rich foods
  • Ensure you get enough omegas in your diet

If the damage is done how can I repair it?

Can the skin barrier be repaired? Yes, it definitely can.

But you will need to help it along. Start by reviewing and following the steps below. Depending on the extent of the damage it could take anything from a couple of weeks to six months to get it back to optimal functionality. But it's worth persevering as you'll be preventing future issues.

Click on the + to expand each section and read more.

#1. Try to find the root cause 

Sometimes this is obvious. If not, it’s an idea to revisit the 7 main causes of damage we listed at the beginning of this article. Are you over-exfoliating? Have you changed your skincare routine or washing powder?

It may take a little trial and error but if you know what you’re dealing with it will make it easier to treat and prevent it from happening in the future.

#2. Stop exfoliating

If you have a damaged skin barrier you must stop exfoliating for a while. You must allow the skin to have time to regenerate and repair. If you continue to exfoliate you will just exasperate the problem.

Once the symptoms are resolved you can slowly reintroduce exfoliation to your routine.

#3. Revisit your routine

With a compromised skin barrier you should go back to basics.

Follow a basic 3-step skin routine while your barrier is recovering.

Cleanse, moisturise and protect with gentle, natural products.

What you want to do is to reduce any chance of irritation on skin that is already irritated.

#4. Ensure you are using products free from irritants

Check the ingredients on the skincare (and cosmetic) products you are currently using.

Sensitive skin or a damaged skin barrier might not be able to handle certain ingredients.

Ingredients that can be irritants include:

Sulphates, parabens, petroleum, fragrance, glycolic acid, lactic acid, benzoyl peroxide and alcohol (Ethanol)

If you can stop using products containing irritants you will give the skin the best chance of not getting irritated more than it already is.

#5. Keep out of harsh environments

This might be easier said than done. What you want to do is to reduce exposure to extreme heat or cold as much as you are able.

Whether you can stay out of the sun and sit in the shade or you are wrapping up in the cold, you want to give the skin barrier the greatest chance of recovery.

#6. Don’t wash your face in a hot power shower

If you already have a skin problem it’s a really bad idea to put your face into a hot powerful jet of water.

Not only will you be stripping the skin of any oils that it is producing to repair the damage but it will increase the chance of symptoms getting worse and damaging the skin barrier further.

Keep to a gentle cleansing routine.

Ingredients to look out for

When selecting skincare products it’s helpful if you know what to look out for.
We mentioned above some irritants that you may want to avoid. But what about the good stuff?

Below we've highlighted some superstar ingredients that are skin barrier saviours.

  • Your skin has a built-in system for moisturising the skin, but this doesn’t always provide enough hydration.
  • Squalane is a natural moisturiser that mimics the skin’s natural oils which makes it a very effective hydration booster.
  • It is also a natural antioxidant.

Adding Omegas to skincare products provides balanced hydration of the skin. Reducing breakouts and signs of ageing.

They regulate the skin’s oil production, improve moisture and elasticity and also soften and smooth dry, flakey skin and soothe irritation.

Hyaluronic Acid is produced naturally in the body, found in the fluids of the eyes and joints. It acts as a natural lubricant.

In skincare, it is used to retain water and therefore retain hydration. It helps the flexibility of the skin, reducing wrinkles and lines.

Peptides are the building blocks of proteins that are crucial to the function and appearance of the skin.

By applying peptides topically, they act as a stimulant prompting the skin to rejuvenate and generate new collagen and elastin.

Allantoin is a compound found within the human body and many plants and animals.

It’s a fantastic hydrator, and mild exfoliator and has effective anti-inflammatory properties. It soothes, moisturises and protects the skin.

Glycerin draws moisture from the air to keep the skin well-hydrated, reducing water loss.

Its presence on the skin supports the skin barrier by aiding moisture retention, even when facing detrimental environmental factors such as pollution.

Build a Skincare Routine to Repair & Protect Your Skin Barrier

Moisturisers help avoid water loss and ensure skin remains healthy and balanced.

Hyaluronic acid spritz toner

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