ALL ABOUT THAT BASE: what is the skin barrier, anyway?
These days, we hear from reputable dermatologists to trending influencers alike about repairing the barrier. This is quite an about-face from the early 90s when we were stripping every drop of oil from our skin to achieve that elusive matte finish. While beauty trends are often arbitrary and constantly changing, in recent years, I’ve noticed an overall trend towards prioritizing skin health and a glow-from-within mindset. Our lifestyle choices are written all over our skin, and when we align ourselves with prioritizing true health, our skin shows it, because when we care for our skin, we are caring for our whole body.
Before we dive into the Barrier Defense System, let’s have a quick biology review
Our skin is comprised of three layers: the epidermis, dermis, and hypodermis.
HYPODERMIS
The deepest layer of skin consists mainly of fat and loose connective tissue with circulatory and nerve vessels. This layer's main role is to provide structure, insulate, and protect from blunt force trauma. It gives our faces a plump and supple appearance. As we age, this layer thins out, creating sagging skin and loss of structure.
DERMIS
The middle layer of your skin contains connective tissue, blood vessels, oil and sweat glands, nerves, hair follicles, and other structures. Connecting the dermis to the epidermis is a layer called the dermal-epidermal junction (DEJ). This very small layer plays a very big role in the tightness and tone of your skin. The DEJ is shaped with low troughs and high ridges to increase its surface area, giving your skin a thicker, toned, and sculpted look. As we age, the troughs and ridges begin to flatten out, effectively reducing its surface area, making the skin less resilient and elastic. This increases the appearance of expression lines, jowls, and sagging skin. When I perform facial massage, I often target the DEJ using stimulating strokes that help sculpt and firm the tissue. Though it's temporary, regular treatments can improve overall health, resilience, and appearance of mature skin.
EPIDERMIS
The outermost layer of skin, while the thinnest, is composed of 5 layers of its own, each performing vital tasks including proliferating new cells, creating the protective melanin that gives our skin its color and helps filter UV rays, immunological functions that prevent bacteria, fungi, yeast, and viruses from causing breakouts and potential serious harm.
The living cells of the epidermis are called keratinocytes. As these cells make their journey from the basement membrane of the epidermis to the outermost layer, the Stratum Corneum, they lose most of their water and die, transforming into strong keratinized cells called corneocytes. This process takes about 4-6 weeks, depending on age. This is why most facial treatments are suggested every 4-6 weeks.
In addition to the basic organelles we see in all living cells, skin cells also contain Natural Moisturizing Factors. NMFs are an important category of water-soluble ingredients, some of which include amino acids, lactic acid, sodium PCA, various sugars electrolytes, peptides, hyaluronic acid, glycerin, and glycosaminoglycans (GAGS). These crucial constituents contain everything we need to maintain a healthy barrier; however, like most things, they deplete as we age.
Surrounding the corneocytes is a lipid bilayer called the extracellular matrix, acting as a kind of cement that binds the cells together in a strong, flexible, and supple protective layer.
For my fellow science nerds:
A Lamellar Lipid Bilayer is where the polar head groups of the lipids face the aqueous phase on both sides of the bilayer, and the hydrocarbon chains oppose each other inside the Bilayer. Which is just fancy-schmancy formulator talk for a multi-layer barrier consisting of both water and oil-soluble parts, naturally arranged by the ionic charge (attraction vs repulsion) of the molecules
Lipids are a broad group of organic oil-soluble materials such as fats, oils, waxes, fat-soluble vitamins such as A, D, E, and K, hormones, ceramides, cholesterol, free fatty acids, monoglycerides, diglycerides, phospholipids, and more. The functions of lipids include moisturizing, softening, storing energy, cell signaling, and acting as structural components. Lipid based products generally have an easier time penetrating the skin as the active ingredients seep into the extracellular matrix surrounding the cells.
Corneocytes of the Stratum Corneum, together with the Lipid Bilayer, create the selectively permeable barrier we know as the Skin Barrier, also called the Lipid Barrier, Moisture Barrier, Skin Microbiome, or Acid Mantle. This Barrier Defence System protects the skin from harm, including abrasions, light, heat, and pathogens. Because the lipids are made from fats and oils, water is easily kept from leaving or entering the body. The corneocytes eventually shed as new keratinocyte cells replace them.
Now that we understand what a healthy barrier is and does, let's look at what happens when this system becomes impaired.
A DISORDERED BARRIER
I believe that almost all our skin concerns and imbalances stem from a disordered barrier.
Here is a small example of some of the ways the barrier can become disordered.
Overly Stripping/Drying Formulas
As we’ve learned, we need those precious oils to help protect our skin from things like water loss and protection from pathogens and environmental stressors like UV rays, temperature and wind exposure.
Not Cleansing Properly
Dirt, grime, environmental pollutants, and oxidized sebum (oil that has been exposed to oxygen, producing free radicals which contribute to the visible signs of aging all clog the pores creating a dull, uneven, congested appearance that can lead to comedones (black and white heads) which may progress to active acne lesions. There has been a recent trend to only cleanse once a day and/or use a micellar water and while I can see the validity of this method for those with mature or dry/dehydrated skin, but its not for everyone! I know its controversial for me to even say it but I think most people should be cleansing twice a day with an appropriate cleaner(s) for their skin type. Conversely, over cleansing or using too harsh of a cleanser will also cause a disordered barrier.
Under Exfoliating
While we do want some dead skin cells, too much can lead to pore congestion and a dull lifeless appearance. Some schools of thought, specifically Corneotherapy, believe the skin contains everything it needs and exfoliates itself at a proper rate without the need for chemical or abrasive exfoliation. While I do subscribe to this theory, there's a pretty big caveat missing; the skin must be healthy with no breaks in the surface and an intact barrier system (UV filtration, acidic microbiome, Lipid Barrier preventing water loss and entry of pathogens). There must also be adequate hydration and available resources for inevitable repair. Cells must have enough energy to perform their tasks. That’s a pretty big list. Exfoliation is a topic deserving of its own blog entry…which is coming soon! Personally, I find an enzyme treatment once every 7-10 days is perfect. How often you exfoliate depends on the health of your barrier and if you are using any other exfoliants.
Over Exfoliating
Guilty! I’m grateful for my esthetics teacher, who, with no tact and all attitude, looked me dead in the eyes and said why are you even using this? She was referring to the glycolic serum I was using twice a week. Which doesn’t seem so out of the ordinary, in fact, exfoliating three times a week is the most commonly heard advice. Having learned my lesson the hard way, I now understand the way it was formulated and the way I was using it was destroying my barrier by repeatedly breaking down the bonds of the my Lipid Matrix enough that over time, the top layer of my Stratum Corneum no longer existed and all the precious waters of this Mature skin type evaporated away as if it were never there in the first place.
Lipid Deficiency
Did you know those suffering from acne are deficient in linoleic acid, a lipid found in abundance in Safflower, Grape Seed, and Sunflower oils? I know, it feels a little counterintuitive to put oil on Acneic skin, but I’ve seen it work firsthand. When we think of Oily/Congested skin, it's a seemingly rational thought to use astringent and deeply clarifying products to remove the excess oils. But not all oils are created equally. Some will exacerbate breakouts, especially the comedogenic oils like castor and coconut* which will almost guarantee a breakout for someone with oily skin. But what is comedogenic for some is exactly the occlusive other skins have been craving. Dehydrated skins want the occlusive nature of heavier oils like Oat Emollient and Cocoa Butter. My favorite oils for oily skins are rosehips seed and blueberry seed. They are similar in composition, being high in essential fatty acids and antioxidants. Both of these oils reduce the appearance of expression lines, normalize sebum production, decrease inflammation, and encourage a bright, even tone.
*No skin type should ever use coconut oil on their face. The molecules of this oil are too large to penetrate the extracellular matrix and will sit on top of the skin creating a non-breathable barrier trapping bacteria, dirt, and debris against the skin.
Use of certain surfactants, emulsifiers, and preservatives
Again, this is a Corneotherapy theory, for which I still have the same caveats. I’ve been very skeptical of this theory in the past; however, as a skin care formulator, I’ve put some of these theories to the “test” and have found results that support it. Now, you have to keep in mind my laboratory is in my kitchen, and I’m not performing tests with any real or measurable data, just my anecdotal experience.
If you're anything like me and you’ve experienced severe and chronic dryness, you’ve likely tried just about every cream under the sun to no effect. According to Corneotherapy, this is because most traditional emulsifiers, the stuff that binds oil and water together, belong to an umbrella class of Surfactants, or Surface Active Agents. These surfactant emulsifiers, once in the skin, do not stop emulsifying the natural oils of your skin. With all your own lipids bound up, it disturbs the arrangement of the Lipid Bilayers, which creates openings and gaps in what should be your continuous barrier. To add insult to injury, we also get what is aptly called the “wash out” effect, when your natural oils are transported out of your skin during contact with water. It might sound like a stretch, but when I moved to making my moisturizers and serums with *biomimetic polymers and polysaccharides that form jelly-like matrices which mimic our own Lipid Bilayers, that’s when my skin really started changing for the better. I noticed immediate results, but it was 6 months of consistent use before I could say my barrier was intact. As a side note, it can be overwhelming to navigate skin issues and frustrating when we spend money on products we hope will work, but don’t quite measure up. Invest in yourself and be patient; healing takes time.
*BioMimetic is a relatively new term that originated in the 50s by Dr. Otto Schmitt, who was an American inventor, engineer, and biophysicist, to define the transfer of ideas and analogues from biology to technology. You will see this term used more and more in the beauty industry as its meaning has expanded to include the mimicry of the skin’s structure, function, and/or contain biomimetic ingredients, which are the ingredients we naturally find in our skin such as Lipids and NMFs.
Alcohol and Caffeine Consumption. Eating Too Much Sugar and/or Fried Foods
This one mostly speaks for itself, as we all know our gut and skin are directly connected; whatever is going on in our liver can be seen in our skin. This one might surprise you, though: Glucose and fructose link to the amino acids present in collagen and elastin that support the dermis. When this happens in cooking, we call it caramelisation. When sugar binds to proteins in the skin, we call it glycation. This process is accelerated in all body tissues when sugar is elevated and is further stimulated by ultraviolet light in the skin and produces whats known as Advanced Glycation End Products (AGEs) which are harmful compounds that obstruct wound healing, reduces skin lipid content, causes apoptosis (cell death) of the keratinocytes of the epidermis, and promotes the production of melanin in melanocytes which cause hyperpigmentation issues such as sun/liver spots and melasma. This dramatically increases the appearance of most age-related concerns, appearing as deep, crosshatched wrinkles. Drink your water and wear your sunscreen!
Not Drinking Enough Water
Also a pretty basic one, but you’d be surprised how many of us struggle to get the water we need on a daily basis, myself included. Lack of hydration in the skin can create a puckering of the Lipid Bilayer and a less-than-plump appearance, which accentuates expression lines. Pro-tip: The hydration level of your skin is obviously dependent on the amount of water you have available in your body, however, your skin's hydration is based on the amount of water you had when the skin cells were forming. Remember that it takes a full skin cycle of 4-6 weeks for the cells to make their way up to the surface, so however much water you had at the time of proliferation is the amount you have to work with. Add some barrier dysfunction on top of that, and kiss your sweet hydration goodbye. You can temporarily mask this by hydrating the Stratum Corneum topically with hydrosols and humectants such as Hyaluronic Acid, Sodium PGA, and Snow Mushroom extract, then creating an artificial barrier with an oil or lipid-based cream. This is a band-aid. The only way to get plumped, glowing skin is through internal hydration. Start increasing your water now and be patient, you’ll see some immediate improvement, but you’ll need a complete skin cycle before you see full benefits.
Lack of Sleep
Our bodies need deep sleep to regenerate and reorganize, file away memories in their proper places, repair injury, and reinforce our immune system. Without proper sleep, our skin appears dull and lifeless, our eyes often sinking further into our skull and casting deep shadows over our already darkened under-eye area.
Stress
The connection between mind and body is irrefutable. Stress can be defined as anything that overwhelms the body’s ability to cope with stimuli presented. Over time, chronic stress can have a dramatic impact on health, including headache, migraine, digestive issues, muscle tension and pain, sleep disturbances, hormonal imbalances, and even cardiovascular disease. Here’s an excerpt from an article published by Harvard Medical School:
Studies show that both acute and chronic stress can exert negative effects on overall skin wellness, as well as exacerbate a number of skin conditions, including psoriasis, eczema, acne, and hair loss.
But it’s not just a one-way street. Research has also shown that skin and hair follicles contain complex mechanisms to produce their own stress-inducing signals, which can travel to the brain and perpetuate the stress response.
Sun Exposure
Last but certainly not least. UV light and heat from the sun are likely the cause of the most dramatic, visible signs of aging. UV light breaks down the precious collagen and elastin in our dermis, where they provide structure, elastic resilience, and plumped features. We only have a certain amount of collagen and elastin fibers present in our dermis, and when they are damaged, it’s permanent. I’ll be debunking collagen in another post, so stay tuned! Sun exposure also rapidly dehydrates the tissue through evaporation by thermal excitation of the cells.
TRANSEPIDERMAL WATER LOSS
All Barrier disorders have one thing in common. Transepidermal Water Loss, or TEWL. A disordered Barrier, whatever its cause, has gaps in its protective layer comprised of dead skin cells and lipid matrix. When these gaps are present, we are no longer protected from natural evaporation or environmental pollutants. When dehydration is present, the lipid matrix puckers as the outer edges of your skin cells lift away, creating an uneven surface not unlike a sponge that has been left to dry and its corners have turned up.
When you apply oil over dehydrated skin, it prevents further water loss but does not hydrate the tissue. In my experience, this leads to an unpleasantly shiny appearance but not a dewy glow. My theory is that the oil coating the uneven surface of those curled up corneocytes catches and reflects the light differently than it would if the skin were smooth. Dehydrated skin is also slow to absorb oil, so it sits on the surface much longer. To treat this, I have found that performing gentle massage on the face increases both the absorption rate and depth. In addition, water-based essences and serums that are made with jelly matrices like synthetic polymers, plant polysaccharides, and protein film formers (peptides, amino acids, and collagen protein) with NMFs are applied under an oil or cream. And when I say cream, I mean cream. What does that mean? In the formulating world, there are two basic types of emulsions: water-in-oil (where drops of water are suspended in an oil base) and oil-in-water emulsions (where drops of oil are suspended in a water base). A cream has a higher concentration of oil to water, making it a water-in-oil emulsion. Conversely, an emulsion with a higher water content is called a lotion.
While your skin type may fall into a general category, due to bio-individuality, our skin is as unique to us as our fingerprints. The effects of a disordered barrier are going to look and behave differently for every person. When we look for treatment options, we sometimes ask what came first, the disordered barrier or the dis-order itself. Personally, I don’t think it matters; the treatment is the same; we always start by treating the barrier first.
For example, a person with oily skin and a disordered barrier may end up with what is commonly referred to as combination skin. How can you have dry and oily skin? We have to start thinking about skin in terms of water and oil. It’s quite common to have oily skin prone to breakouts that is also dehydrated, or water dry. When we combine oily skin with a disordered barrier and introduce allergens, environmental pollutants, and pathogens, breakouts become almost inevitable, as nothing is protecting you from the dirt, grime, and pollutants clogging up your pores. With a weakened barrier, pathogens can get deep into the epidermis, causing everything from a minor breakout to eczema, contact dermatitis, sensitization, perioral dermatitis, psoriasis, candida overgrowth, and papular rosacea. This is why it’s important to protect the skin that protects you.
In my opinion, combination skin is one of the hardest skin types to treat because the products used for oily skin are often astringent and drying which exacerbates the issue of gaps in the barrier leading to more water loss and reduced barrier function, ie more bacteria can get into the pores where they feast on your sebum and proliferate rapidly. The barrier health must be addressed first before any real headway (pun intended) can be made on acne, especially cystic acne.
Another example would be someone with sensitive/sensitized skin. This person may start out with normal skin but is topically exposed to harsh environmental pollutants such as industrial disinfectants, metals, synthetic fragrances, and even lavender essential oil, which is a known sensitizer (unfortunately, I can speak from experience on that one). Over time, exposure to these chemicals causes a local reaction on the body where it came into contact with the sensitizing material. Not to be confused with an allergic reaction, which shows up systemically, such as hives all over the body, not just the initial point of contact. The areas of the skin affected by topical exposure to harsh chemicals are often inflamed, irritated, painful, dry, hot, and sometimes itchy. That sounds like a disorder barrier to me. As sensitization increases, barrier function decreases in a self-perpetuating feedback loop. Look for gentle ingredients that are cooling and demulcent like cucumber, aloe, snow mushroom, chamomile, and calendula with your protein film formers (amino acids, peptides, collagen protein etc) and moisturizing cream.
Before we part, I want to leave you with one last golden nugget…or ratio, as the case may be. As both a formulator and esthetician, if I had to choose one ingredient as the best in its class for treating barrier dysfunction, it would be Ceramide Complex, which is a concentrated formulation consisting of a biomimetic, multilamellar system identical to lipids found in the skin. When combined with phospholipid liposomes and cholesterol in what is colloquially known as the golden ratio of 3:1:1, it can dramatically alter the arrangement of your Lipid Bilayers, returning them to their multi-lamellar structure. A word to the wise: exercise caution when looking for products with Ceramide Complex. Ceramides are exorbitantly expensive as a raw material, and you get what you pay for…those inexpensive serums likely do not contain the required percentage of this active to do anything more than have good label appeal. As I understand it, Ceramide Complex is only made by one major manufacturer and if your label does not read “Ceramide NP (and) Ceramide AP (and) Ceramide EOP (and) Phytosphingosine (and) Cholesterol (and) Sodium Lauroyl Lactylate (and) Carbomer (and) Xanthan Gum (and) Water (and) Phenoxyethanol (and) Ethylhexylglycerin” in that specific order, you are not getting a product with Ceramide Complex. Don’t get me wrong, ceramides on their own do wonders for the skin, but this golden ratio complex really is something to write home about.
I hope this article has been a support to you on your journey and as always, comments and questions are most welcome.
Thank you so much for your continued support of my own journey!
Vanessa has been in private practice for 20 years as a licensed massage therapist, esthetician, Ayurvedic practitioner, herbalist, trauma informed coach, cranio sacral therapist, energy healer, independent educator and most recently, a skin care formulator. Her unique approach blends therapeutic and holistic care with clinical treatments for lasting results that are more than skin deep using her own formulations with potent actives and nourishing botanicals that treat all skin types and concerns. Areas of expertise are calming sensitive skins, deep hydration, restoring barrier function, sculpt + lift facial massage, and hyperpigmentations.
The beauty + cosmetics industry can be an overwhelming field to navigate for a myriad of reasons. Vanessa believes in supporting the growth and abundance of all people working and participating in the fields of beauty and wellness, and strives to meet people where they’re at to provide approachable and genuine care.
Having just relocated to Prescott, Az from Seattle, Wa, Vanessa is interested in growing a community of like minded friends, practitioners, and clients locally in addition to her Seattle community. Your presence and support help to create this lively community and I’m glad you are here.
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