How your skin can maintain itself naturally

Did you know that your skin is able to cleanse, moisturize, exfoliate and heal itself?

Our skin actually needs little in terms of external skincare practices. What it needs is support from the inside (nutrients), and creating the right environment on the outside so that the skin can do its thing. The healthier and more balanced the skin is, the more it is able to maintain itself through built-in mechanisms.

In essence, because our skin is amazingly complex and complicated, our skincare doesn’t have to be.

I hope that, with a deeper understanding of these mechanisms, coupled with a sense of gratitude and appreciation for our largest organ (i.e. our skin), we are able to let go of preconceived notions that for our skin to be healthy and beautiful, it needs to be dependent on products and that the more products we use and the more expensive they are, the more we are doing our skin a favor.

In fact, for most of us, the exact opposite is true!

Here are some keywords before we begin:

Stratum corneum – the uppermost layer of the epidermis (upper layer of the skin, dermis being the inner layer) that consists of dead skin cells (corneocytes) and lipid matrix (oily substances arranged in a sort of matrix that holds the corneocytes together)

Skin barrier (also called lipid barrier) – basically it means the protective function of the stratum corneum layer

Corneocytes – dead skin cells on the surface of our skin (part of stratum corneum), very important for healthy skin

HOW THE SKIN MOISTURIZES ITSELF

Ever heard how “everyone, even oily skin types need a moisturizer”?

This is pretty misleading because our skin needs to BE moisturized, but this isn’t the same as needing to use a moisturizer. Our skin is able to moisturize itself, provided we allow our skin to be healthy and balanced.

Human skin has evolved to be able to independently maintain optimal hydration levels, which is not only essential for the health of your skin but it is also what makes it supple, radiant and beautiful.

After all, moisturizers are a very new invention, and it simply isn’t true that we all suffered from dry skin for millions of years prior to the 20th century!

Loss of water from the skin can be carefully regulated by the built-in mechanisms and functions of the skin’s outermost layer – stratum corneum (SC).

The mechanisms of this aren’t even completely understood (and are pretty complex), and it is therefore impossible to be matched by any man-made skincare product.

The ingredients found in skincare products may actually have a detrimental effect on any one of the specific parts of the skin (upper layer – epidermis), namely the skin microbiome, the acid mantle, the lipid barrier (also called skin barrier) and/or the stratum corneum.

All these components work together to fulfill the epidermis’s main protective role.

Any damage caused to either the skin microbiome, the acid mantle, or the lipid barrier (in other words, the integrity of the stratum corneum layer) has a detrimental impact on the overall ability of our skin to sustain itself.

Our skin moisturizes itself by retaining water in the Stratum Corneum (SC), and it does so in two main ways:

1. Through binding of water molecules by Natural Moisturizing Factors (NMFs) found within corneocytes (matured dead skin cells of the stratum corneum).

The more mature the corneocyte cell is, the larger its surface area, and the more NMFs it can hold (which means more water can be held within the stratum corneum).

As the corneocyte cells move upwards towards the skin surface, they change in size and shape, becoming more flattened in order to increase and maximize the surface area. The bigger the surface area, the more NMFs the corneocyte cells can hold, and thus the more water it can bind to.

Furthermore, this function can be supported by certain helpful bacteria found in the balanced skin microbiome. These bacteria are able to produce proteins and protein by-products that are similar to NMFs.

2. By minimizing water loss due to evaporation from the skin into the environment (referred to as Trans Epidermal Water Loss or TEWL).

This is achieved with the help of an intact and functional lipid barrier and is supported by sebum which acts as a protective layer on the surface of the skin.

The more intact the lipid barrier (coupled with optimal sebum production), the lower the rate of transepidermal water loss.

Our skin, just like the rest of our body, functions in a holistic manner – optimal skin hydration can only take place when all the mechanisms involved are optimally functioning.

In essence, for our skin to maintain optimal hydration levels and especially in environments of low relative humidity, it is crucial that:

• Its corneocytes are fully matured and able to hold the maximum amounts of NMFs
• Its lipid barrier is viable, i.e. fully intact and functional
• Its microbiome is healthy and balanced
• Its acid mantle maintains an optimal pH balance of ~ pH5.
  

  

When these mechanisms are disrupted, our skin is not able to retain or hold onto water as effectively. This can lead to dehydrated skin, prematurely aging skin, sensitive skin and acne. 

Prolonged dehydration can lead to flaking or peeling skin, premature lines and wrinkles, and even atopic dermatitis and eczema.

It is estimated that only 10-15% (if that!) of women have a genetic disorder that prevents their skin from moisturizing itself efficiently, thus requiring the use of external moisturizers to regulate hydration levels, whereas the other 85% is still able to moisturize itself efficiently (with fully functioning mechanisms) when provided with enough nutrients through diet. 

Naturally, having balanced hormone levels plays a major role in sebum production and overall skin health. In the case of hormonal imbalances, our skin’s mechanisms may not be in balance as well. The majority of hormonal imbalances have their roots in gut imbalance, or dysbiosis, which is why gut health is so important when it comes to healthy skin!

The real reasons our skin is not able to moisturize itself efficiently may be any one or (more likely) a combination of these factors below:

1. Our skin barrier is damaged, and our skin is not able to repair itself effectively.

Daily use of harsh, surfactant-based cleansers and make-up removers affect the lipid barrier’s ability to repair itself (although age and diet also play a role). Furthermore, the repair mechanisms rely heavily on the work of enzymes, and enzyme efficiency is highly sensitive to water and pH changes.

Thus, when the skin is dehydrated, the enzymes are not able to efficiently carry out the repair and rebuilding work of the lipid barrier.

2. Our Acid Mantle pH balance is constantly being disrupted, or not in the optimal range of ~ pH 5.

This is probably due to the regular use of skincare products that are not pH balanced to the skin and/or that are disruptive to the skin barrier. Disruption of the skin barrier will also lead to less than optimal pH of the stratum corneum.

3. Our Skin Microbiome is not in a healthy balance.

This could be due to an unhealthy gut microbiome balance and/or the over-use of skincare products that contain relatively strong preservatives or anti-bacterial ingredients that kill the good bacteria our skin needs. All skincare products that have a water component need a preservative to prevent it from spoiling, but this also affects the skin microbiome.

4. Our Corneocytes do not contain enough NMFs because they are not allowed sufficient time to reach full maturity.

This happens mainly from over-exfoliation. which prevents our corneocytes from fully maturing. Matured corneocytes are larger and flatter in shape, with an increased surface area capable of holding larger amounts of NMF’s (manufactured by enzymes within the SC itself) that allow the corneocytes to retain larger amounts of water.

In fact, research has suggested that NMFs play a bigger role than the lipid barrier in maintaining skin hydration!

HOW THE SKIN EXFOLIATES ITSELF

Yes, your skin is also able to exfoliate itself!

It does so through a mechanism called desquamation, where dead skin cells (corneocytes) are shed off continuously through enzymatic action. Specific enzymes made in your skin dissolve away desmosomes, little tunnel-like structures that hold the corneocytes together, after which they can be shed off.

You have probably heard of the 28-30 days skin renewal cycle, but do you know what this actually means? It means that a new skin cell created deeper in the skin takes up about 28-30 days to reach the surface of the skin before it sheds off. However, the uppermost layer of the skin is CONSTANTLY renewing itself through desquamation!

That skin cell goes through a complex journey in those 28-30 days, changing its shape, function, releasing its lipids and fortifying its cell walls. This process of change and function is also a process of controlled and precisely timed cell death, referred to as apoptosis.

By the time the skin cell reaches the uppermost layer of the epidermis, the stratum corneum, it is already considered ‘dead’. But this doesn’t mean that it is useless! Far from it. These dead skin cells are called corneocytes and play a crucial role in our skin’s protective lipid barrier, and our skin’s ability to hydrate itself.

The stratum corneum, although essentially made up of dead skin cells (plus a matrix of lipids holding them together) also houses many important enzymatic mechanisms that are important for the repair and maintenance of a strong and functional lipid barrier, which is crucial in preventing infection and retaining moisture within the skin.

But if the corneocytes are so useful, why are they being shed off constantly?

Our skin continues to renew itself in order to serve its protective function as efficiently as possible. Think of our skin as high-tech armor that is strong and impermeable, yet soft, supple, and incredibly flexible.

Our skin takes a “beating” on a daily basis as we interact with our environment. Minor grazes and micro-cuts are handled effortlessly by the skin’s constant renewal without compromising its protective function.

So for every new skin cell that is made, a dead skin cell has to be shed off in return to maintain the optimal thickness of the stratum corneum. The process of cell renewal and desquamation are two mechanisms that occur in parallel, peaking at night as we sleep, and are precisely timed to go hand-in-hand.

We like to hurry this process up with exfoliating products, hoping to reveal “fresh, new, glowing skin”. However, removing too many layers of corneocyte cells too often (with over-exfoliation), causes more harm than good.

Apart from disrupting the skin’s microbiome, acid mantle and lipid barrier, the skin’s self-moisturizing and self-hydrating mechanisms are also greatly impaired.

This is because, in order for our skin barrier to remain properly hydrated, optimal amounts of Natural Moisturing Factors (NMFs) are required. Corneocyte cells make and hold optimal amounts of NMFs, but this is a process that takes time and maturation. When we actively remove the top layers of our dead skin cells, we are removing precious matured corneocyte cells and their NMFs as well. The younger, more immature corneocyte cells that are left do not contain sufficient amounts of NMFs.

This lack of NMF’s translates to dehydrated skin over time, and with a damaged and disrupted skin microbiome, acid mantle and lipid barrier, this ultimately leads to the other symptoms of imbalance (pimples, redness etc). What’s worse – the lack of hydration makes the skin unable to repair all this damage effectively and quickly enough, leading to signs of over-stressed skin, or prematurely-aging skin.

The skin in this state is being handicapped of its basic functions and mechanisms, and then highly dependent on moisturizers, skin repairing creams and other treatments!

When we allow our skin to exfoliate itself naturally, we ensure the health and optimal functions of all the mechanisms and functions that exist within the epidermis, namely the skin microbiome, the acid mantle, the lipid barrier, and of course the cell renewal process.

However, it is very important that our skin and body are healthy for the process of desquamation (as well as all other processes in the skin) to take place, proof of which is clear, radiant and beautiful skin! Apart from healthy eating and lifestyle, skincare products and routines also have a great impact on the health of your skin.

The process of desquamation is highly complicated and not yet completely understood by science. From what is currently known, a simplified explanation of this process looks like this diagram below.

Or even more simply:

What is important to understand here is:

• The desquamation process takes place hand-in-hand with the cell renewal process
• Enzymes regulate the desquamation process by dissolving away the bonds that hold the corneocytes (dead skin cells) together, allowing them to be shed off seamlessly
• This enzymatic action is highly dependent on optimal hydration levels and pH balance (of pH5) within the stratum corneum

HOW YOUR SKIN CLEANSES ITSELF

We all know that cleansing is the basis of any decent skincare routine, but did you know that the act of cleansing potentially does the most damage and disruption to our skin?

These are our skin’s fundamental mechanisms in preventing pathogen infection and dehydration, so it is no wonder that daily assaults (through cleansing alone) can lead to unbalanced skin that is dependant on a vast array of skincare products just to appear normal!

If we want happy and healthy skin, and skin that is independent, we need to re-evaluate our obsession with removing dirt and excess oils. Do not worry: The solution does not lie in a total abandonment of hygiene!

The solution lies in an understanding that healthy skin is self-cleansing, and that the mechanisms and technology our skin employs to do so is more effective and much more high-tech than the cleansing methods we are so fond of.

Here are 4 ways healthy skin cleanses itself, from the inside out, and how we can support these mechanisms. When we do so, we enhance our skin’s natural protective and hydrating abilities, which translate to smoother, clearer and more radiant skin, no matter our age!

1. IMMUNE DEFENSE MECHANISMS THAT PREVENT INFECTION

Healthy skin is AWESOME at defending itself from infection and disease, a crucial aspect of keeping itself ‘clean’!

Skin employs 3 different methods (physical, biological and chemical) and 5 separate mechanisms. These mechanisms all operate holistically (depending on each other while supporting each other), protecting your skin and every living cell within it against infection and disease 24/7!

Before we look into these 5 mechanisms, let’s understand the term ‘pathogens’ first. Pathogens are disease-causing micro-organisms such as bacteria and viruses. However, not all micro-organisms are pathogens as their mere presence does not cause disease. In fact, some are beneficial and necessary for healthy skin.

This explains why the Cutibacterium acnes bacteria (formerly Propionibacterium acnes), which is an abundant and useful member of a diversified and balanced skin microbiome, does not cause acne in healthy skin.

However, in conditions that may favor its rapid multiplication, such as a clogged pore, it then becomes a pathogen because its numbers are too high and the subsequent high amounts of metabolites it produces become toxic to the skin because your skin is not able to deal with it effectively enough!

5 mechanisms of protection against pathogens:

1. A healthy, balanced and diversified skin microbiome

The number of the C.acnes bacteria, as well as all the other micro-organisms in your skin, is kept in check by your skin’s wide variety of other bacteria populations.

Each population will defend its territory from other invading microorganism species (be it viral, fungal or bacterial) by producing their own versions of Free Fatty Acids (FFAs), Phenol Soluble Modulins (PSMs), and Antimicrobial Peptides (AMPs) that prevent potential pathogens from over-multiplying. Your skin microbiome also communicates with your skin’s immune cells, providing feedback to your immune system to produce an inflammatory response when there is a threat of a possible pathogenic attack.

2. Epidermal cells that produce their own Antimicrobial Peptides (AMPs), and play an active role in maintaining the microbiome balance

In fact, melanocyte cells (the cells that produce melanin in your skin) and keratinocyte cells can also engulf and ingest pathogens!

3. pH balanced stratum corneum (acid mantle)

pH balance is crucial to support the good bacteria on your skin but is not suitable for foreign pathogenic bacteria or micro-organisms. This acidic environment is your skin’s chemical defense mechanism against foreign pathogens. Interestingly, sebum on its own also contains FFAs that act to protect against potential pathogenic attack!

4. Healthy and robust skin barrier

When your skin’s lipid barrier is strong, it acts much like a solid brick wall that does not allow pathogens from infiltrating further into the skin and into the bloodstream.

It also prevents irritants from entering your skin, saving your immune cells from having to produce an inflammatory response, and in essence reduces inflammation!

5. Biological defense mechanism made up of immune cells

These cells lie deeper within the epidermal and dermal region of the skin. It is made up of the abundant immune cells which stand guard 24/7 and serve as gatekeepers.

They are constantly communicating with the body’s main immune system or control center (in your gut!) in case of a pathogen attack – where it will require back up or more immune cell soldiers to kill off the invaders.

2. CELLULAR CLEANSING

The most basic way our skin cleanses itself is at the cellular level, with the help of a healthy lymphatic flow.

So many important functions occur at the cellular level, from the replication of new cells at the basal layer of the epidermis to the formation of various enzymes, lipids and proteins that all play a crucial role in keeping the skin healthy, balanced and functioning at its best.

When each skin cell is fully nourished by a healthy blood supply, and its waste products and toxins are removed efficiently with the help of a healthy lymph flow, our skin is able to conduct all its complex functions and mechanisms optimally.

Optimal Lymph Flow = Clean Cells = Healthy Cells = Healthy and Happy Skin!

To support optimal cellular cleansing, we need to ensure that our lymphatic flow is optimal as well. We have three times more lymphatic fluid than we do our blood but our lymphatic system does not have a pump, like our heart. That means our bodies need to rely on other ways to move the lymphatic fluid through our body to keep us healthy.

The best and simplest ways to ensure optimal lymphatic flow are practicing regular deep breathing, laughing more (the deep belly types!), exercise (including walking, running, jumping, etc) and performing simple lymphatic drainage face massages in our daily skincare routines!

3. CONTINUOUS CELL RENEWAL & EXFOLIATION

We already know that our skin is naturally capable of exfoliating itself. When our skin is healthy and balanced and its desquamation mechanism is working optimally, we wake up to a fresh new layer of skin every morning!

Stem cells in the base layer of our epidermis produces new cells continuously (although the rate of this process naturally slows down as we age, and is also determined by the rate of our desquamation process), effectively renewing our epidermis layer every 28 days or so.

Healthy skin that renews and exfoliates itself naturally does not require mechanical exfoliation because it effectively exfoliates itself constantly! Why skin appears dull or flaky is because it is in an unhealthy state, and therefore our desquamation mechanisms are not functioning at their best.

We can help to restore our skin’s desquamation mechanism by ensuring that:

1. The pH of our skin remains optimal
2. The mentioned skin’s hydration mechanisms are all intact

4. DEEP PORE CLEANSING BY THE FREE FLOW OF SEBUM & SWEAT

Oh, the dreaded oil on our skin, a.k.a. sebum!

Sebum, as you have learned already, is a crucial component of healthy and self-maintaining skin.

As it is secreted onto the surface of the skin from tiny sebaceous glands inside the pores (that contain hair follicles), it also cleanses away your pores on its way. Note it is getting secreted, not excreted, the former indicating it is useful, and the latter that it is waste.

Furthermore, when we perspire (and we do so more or less continuously also), sebum and sweat flow outwards together, cleansing the skin and thus maintaining a healthy ‘clean’ environment that prevents bacterial overgrowth and is infection-free.

Related: 5 Reasons I Don’t Wash My Face In The Morning

But why is that a lot of us suffer from consistently recurring clogged pores?

Clogged pores occur due to a few reasons:

1. Sub-optimal desquamation process – When the skin is not exfoliating itself optimally, dead skin cells accumulate inside the pore, and this also causes sebum to be trapped there, creating the perfect environment for the C.acnes bacteria to over-multiply (due to lack of oxygen). The skin responds to this by creating an immune response in an attempt to contain the rapidly multiplying C.acnes bacteria from spreading and causing further imbalance to the rest of the skin! This phenomenon is what we recognize as pimples or acne.

Sub-optimal desquamation can be the result of chronic irritation (often resulting in hyperkeratinization, the process which results in over-accumulation of protein keratin on SC). Also, when the desmosomes connecting corneocytes aren’t being broken in a timely manner as well (often due to hormonal imbalances), the desquamation will again be sub-optimal.

Thus, the only effective way to minimize clogged pores for the long term is by ensuring that your skin’s desquamation mechanisms are optimal.

2. Oxidation of sebum – Vitamin E is the main antioxidant on the surface of your skin and gets secreted there together with the sebum. Its role is to protect the delicate lipids from oxidation. However, when our body is under stress for different reasons, with low levels of vitamin E and low overall antioxidant status, oxidative damage can run rampant and oxidize components of sebum, particularly squalene, which then turns into pore-clogging substance squalene peroxide (note that squalane isn’t the same substance, it is in fact the saturated version and not prone to oxidation).

This is also why the oilier the skin is, the more prone it is to acne, but we also see cases where people with oily skin do not have acne, likely due to sufficient antioxidant status of the sebum and generally healthy skin.

I hope that this post has convinced you that it is imperative to be mindful of the inner workings of the skin in order to actually achieve healthy, clear and glowing skin we all wish for!

The less we interfere with our skin, the more we allow and welcome health to our skin. Remember: It isn’t about what YOU want, it’s about what your SKIN wants. More often than not, your skin just wants to be left alone.

In radiant skin health,

Salmah & Sara

This blog post is written by an amazing skin educator Salmah, and edited by me (Sara). Salmah shares many helpful tips on her Instagram @empoweredskincare

About Sara

Hi there! My name is Sara. I am a molecular biologist who has spent 15 years figuring out the perfect skin care for sensitive, acne-prone skin and now I want to teach you all about it!