Introduction to the Skin Barrier
The skin is the largest organ of the human body, and it plays a crucial role in protecting us from external threats. One of its most important functions is acting as a skin barrier. The outermost layer of our skin is called the skin barrier, also known as the stratum corneum or epidermal barrier. It plays a crucial role in maintaining optimal hydration levels within our bodies and keeping harmful substances out . Understanding how this protective shield works can help us take better care of our skin and overall health.
The Composition and Functionality of the Skin Barrier
The skin barrier is composed of dead skin cells (corneocytes) embedded in a lipid matrix made up of ceramides, cholesterol, and free fatty acids. This unique structure resembles a brick wall where corneocytes are bricks and lipids are mortar holding these bricks together. This protective layer isn't just a static shield; it's a dynamic structure that constantly regenerates itself; Prevents water loss from inside our bodies while blocking harmful substances like allergens, bacteria, viruses, and environmental pollutants from penetrating into deeper layers of our skin. It also helps maintain the right balance between moisture and dryness on our skin surface.
As new cells are produced at the base of your epidermis (the top layer of your skin), older cells are pushed towards the surface where they eventually die and flake off. This cycle takes about 28 days in young adults but slows down as we age.
The skin's mildly acidic barrier serves as a defense, acting as a buffer to hinder the proliferation of harmful bacteria, viruses, and fungi. This protective function helps prevent skin damage and minimizes the risk of infections and various skin conditions. This acidity, known as the acid mantle, is especially important to protect around wounds, as the skin’s acidity is necessary for many of the biological interactions that occur during the healing process.
Why is the Skin Barrier Important?
The skin barrier serves several crucial functions. It protects your body from free radicals and harsh environments, and it prevents infections. It acts as our first line of defense against, harmful environmental toxins and pathogens that could penetrate your skin and cause adverse effects inside your body. Additionally, the skin barrier prevents the water inside your body from escaping and evaporating, which would leave you completely dehydrated.
When functioning optimally, your skin barrier helps keep your complexion smooth, hydrated, and glowing while preventing conditions like dryness, irritation, inflammation, acne, eczema or premature aging.
Moreover, maintaining an intact skin barrier is crucial for preventing transepidermal water loss (TEWL), which refers to the evaporation of water from your skin to the environment. An overabundance of TEWL may result in dryness, irritation, and heightened sensitivity, indicating a potential compromise in your skin barrier.
Signs of a Damaged Skin Barrier
The skin barrier can be damaged by a variety of factors, both external and internal. External factors include a too humid or too dry environment, allergens, irritants, pollutants, too much sun exposure, alkaline detergents and soaps, exposure to harsh chemicals, and over-exfoliation or over-washing. Internal factors include steroids, psychological distress, and genetic factors that may make you more prone to certain skin conditions like atopic dermatitis and psoriasis1.
A damaged or compromised skin barrier can lead to various skin issues. Some common signs that your skin barrier might be impaired include:
- Dryness or flakiness
- Redness or inflammation
- Increased sensitivity or irritation
- Itchy or rough skin
- Breakouts or acne
These symptoms occur because when the skin barrier is damaged, it allows irritants and allergens to penetrate more easily, leading to inflammation and other skin problems. Moreover, a compromised skin barrier can't retain moisture effectively, resulting in dry and dehydrated skin.
How to Protect and Strengthen Your Skin Barrier
To safeguard and rejuvenate the skin barrier, it is advisable to use products that contain oils, ceramides, and other similar ingredients. These ingredients can help repair the skin barrier and prevent further damage. It’s also important to avoid factors that can damage the skin barrier, such as over-exfoliation and exposure to harsh chemicals.
Fortunately, it's possible to repair and strengthen your skin barrier with some simple skincare habits:
- Aggressive cleansers can strip away your skin's natural oils, causing harm to its protective barrier. Choose mild, pH-balanced cleansers that effectively clean without causing excessive dryness.
- Moisturisers help to replenish the lipids in your skin barrier, improving its ability to retain moisture. Look for ingredients like ceramides, fatty acids, and cholesterol that are naturally found in the skin barrier. To learn more about moisturisers please read our blog on why to moisturise.
- While exfoliation can help remove dead cells from the surface of your skin, overdoing it can damage your skin barrier. Stick to gentle exfoliants and don't exfoliate more than twice a week.
Protect Against Sun Damage
- UV rays from the sun can damage your skin barrier and accelerate aging. Make sure to apply a broad-spectrum sunscreen rated at SPF 30 or higher every time.
Factors Affecting the Health of Your Skin Barrier
Various factors can compromise your skin barrier function leading to what dermatologists call "impaired barrier function". These factors encompass various elements such as severe weather conditions (extreme heat or cold), air pollution, lifestyle choices like inadequate diet or sleep, excessive exfoliation or the use of aggressive skincare products, stress, aging, specific medications, and underlying health conditions such as diabetes or autoimmune diseases.
If your skin barrier becomes compromised or weakened, it may result in an array of skin issues like dryness, redness, itching, inflammation, or even more severe conditions such as eczema or psoriasis. It also makes your skin more susceptible to infections and accelerates the aging process.
Maintaining and Repairing Your Skin Barrier
Maintaining a healthy skin barrier is crucial for overall skin health. Here are some tips to help you keep your skin barrier in top shape:
- Drink plenty of water and use moisturisers that contain ingredients like hyaluronic acid, glycerin, or ceramides which help attract and lock in moisture.
- Use sunscreen daily to protect your skin from harmful UV rays which can damage your skin barrier.
- Avoid harsh soaps, cleansers or exfuliants that can strip away natural oils from your skin. Opt for gentle, pH-balanced skincare products instead.
- A balanced diet rich in essential fatty acids, antioxidants, vitamins and minerals can help nourish your skin from within.
Get enough sleep
- During sleep, our bodies go into repair mode which includes repairing any damage to the skin barrier.
Should you notice signs of a compromised skin barrier like continuous dryness, redness, itching, or sensitivity, it's crucial to seek guidance from a dermatologist. They can suggest suitable treatments or products to aid in repairing and rejuvenating your skin's protective function.
The significance of the skin barrier cannot be emphasized enough. It's our first line of defense against external threats, maintains our internal balance and plays a crucial role in maintaining healthy, beautiful skin. When we grasp its functionality and proper care, we guarantee that our skin stays robust, resilient, and glowing continuously.
The well-being of our bodies is intricately tied to the condition of our skin barrier. When we comprehend its role and mechanisms, we're better prepared to nurture it, fostering not just beautiful but also robust and healthy skin.
Remember that everyone's skincare needs are unique, so it's important to listen to your skin and adjust your routine accordingly. Always listen to your own body and consult with a professional if you have any concerns about your skincare routine or overall skin health.
Effectively caring for your skin barrier goes beyond mere aesthetics; it constitutes a crucial aspect of upholding overall health and well-being.
Yours Truly, Milinda x
 Yun et al. "Skin barrier function", DermNet, March 2021. Accessed January 3, 2024.https://dermnetnz.org/topics/skin-barrier-function.