María Monterrubio

Too many wellness approaches claim to prevent skin aging through the increase of cutaneous collagen. Which are myths and which are true? Get acquainted with how collagen gets produced and destroyed in your skin and be able to discern what you can do and what works.

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Hi guys! As you may know, collagen is the most abundant protein in our body. The health and youth of the connective tissue in the skin (and virtually every other organ) depend on the appropriate quantities of quality collagen. Let’s get to know how to take proper care of our collagen throughout our whole lifetime!

Why might the distinct types of collagen in the skin decline at any adult age?

The skin has different types of collagen. Some are part of the basement membrane, the structure located right beneath the epidermis that anchors it to the dermis below. There you find collagen IV and collagen VII.

The dermis is much thicker than the epidermis (and the basement membrane) yet has a much lower number of cells. Thus, it comprises a pretty large Extracellular Matrix (ECM). The dermal ECM contains high quantities of fibrillar collagens, namely collagen I and, in lower amounts, collagen III. They constitute about 75% of the dry weight of the dermis. And form highly resilient fibers that impart structure, strength, and elasticity to the dermis and the skin as a whole. 

The cells that produce the vast majority of collagen in the skin live within the dermal ECM and are called fibroblasts. They generate all the collagen types mentioned above and other ECM proteins, such as elastin or fibronectin.

The primary reason behind collagen decay in the skin (that occurs, for example, upon premature aging) is not the mechanical or environmental harm undergone by the collagen molecules themselves. It is fibroblast damage. But let me explain this better.

Fibroblasts can endure just a finite amount of harm throughout their lifetime. To accumulate that degree of damage usually takes them a time (shorter or larger, depending on the person). However, it can also occur in a more dramatic, sort of sudden fashion. Once fibroblasts cannot repair those injuries anymore, cellular damage becomes irreversible. And fibroblasts reach a state of cellular senescence.

The more damaged and senescent fibroblasts you accumulate in your dermis, the lower the quantity & quality of collagen in the skin. At any age, that results in the typical features of skin aging (such as fine lines or skin thinning). Also, it may cause a suboptimal skin barrier function (which can lead to additional skin issues).

Why are damaged collagen-producing cells so harmful? Cannot they be removed and replaced? 

Severely damaged fibroblasts lose the ability to produce growth factors (aka specific molecules that induce cell proliferation). Thus, they cannot give rise to new fibroblasts anymore. They just become inactive and stop making quality collagen. And that is not even the main issue!

The thing is that our immune system can barely whisk them away, so they remain in the dermis causing additional damage. Those severely damaged fibroblasts release harmful inflammatory molecules and create low-grade inflammation that disrupts:

– cellular communication (such as the cross-talk between dermal and epidermal cells)

– the interaction of cells with ECM proteins (crucial for cellular activity)

– and the ECM itself (due to the activation of proteolytic enzymes that destroy it).

Some nascent technologies based on compounds that kill senescent fibroblasts might be relevant in the future. But it’s always better to avoid fibroblast damage in the first place. So let’s get into that!

What are the factors that drive fibroblast damage in the skin? Can I prevent them?

Intrinsic Factors

They are related to your genetics and rate of biological aging (or how well your systems cope with just the simple passage of time – which varies from one person to another – ). They involve, for instance, the inherent effectiveness of your DNA repair systems.

Extrinsic Factors

They comprise your lifestyle (your diet, exercise, whether you smoke, etc.). Also, the skin covers us and has to deal with multiple environmental factors. Therefore extrinsic agents – such as sun exposure or even chemicals you may be exposed to regularly – play a significant role in the skin’s collagen decay. 

Extrinsic factors, such as ultraviolet light from the sun, trigger the key events that harm fibroblasts:

· increase of oxidative stress (free radicals)

· DNA damage

· mitochondrial dysfunction (the mitochondria – the organelle where our cells produce the energy they need – becomes non-functional when the cellular detoxifying systems become saturated and cannot counteract high oxidative stress levels anymore)

· accumulation of oxidized, useless proteins (among them, collagen).

Relationship between Extrinsic & Intrinsic Factors (there’s a lot you can do!)

The drivers of intrinsic and extrinsic injuries largely overlap. For example, both internal and external causes can provoke mitochondrial dysfunction. That means that by reducing external insults (due to your better lifestyle choices 😉 ) you can improve or prevent internal damage. There’s no excuse!

Four key strategies to preserve quality skin collagen for life

1 · Optimize your epidermis: avoid barrier damage & inflammation. Use sunscreen & moisturize your skin.

Sunscreen prevents the ultraviolet B (UVB) rays that reach the epidermis from causing cellular damage (to the DNA, proteins, etc.) and inflammation.

Moisturizing your skin will help your epidermal cells stay hydrated. That will avoid imbalances in the epidermal barrier that protects us.

Moreover, both things will help you evade altering the communication between epidermal and dermal cells and, thus, the spreading of inflammation to the dermis (and fibroblast and ECM injury).

2 · Boost your dermis: avoid ECM damage and nourish your fibroblasts. Use a good sunscreen, hence reduce the amount of UVA rays that reach your dermis. Also, include enough quality proteins in your diet (for instance, lean meat) to not leave your fibroblasts without quality amino acids to build collagen. And reduce processed sugars (they can cause cell and ECM deterioration!).

3 · Enhance your cutaneous antioxidant systems. If you use sunscreen, the antioxidant systems in your skin won’t get depleted so fast. Additionally, you can replenish them by including quality antioxidants in your diet (especially water-soluble vitamin C, lipid-soluble vitamin E) and skincare routine.

4 · Befriend specific collagen boosters. Those are vitamin C and vitamin A (and related molecules, such as beta-carotene).

What skincare products can address collagen decay? Myth & truth.

Collagen moisturizers

They include collagen peptides (small chains of amino acids) and usually contain the ingredient Hydrolyzed Collagen. Peptides may impart good moisturizing properties to the skin. However, they cannot penetrate it easily. Therefore, collagen peptides help your skin stay hydrated but won’t trigger collagen synthesis.

Bear in mind that collagen peptides in different collagen moisturizers may not provide similar moisturizing properties. The quality of the hydrolyzed collagen included in skincare products is entirely up to the brand – and the supplier (of collagen) they choose –. And that quality varies with the source of collagen (fish, bovine, etc.) and the specific chemical or enzymatic processing that yields the peptides.

Retinoids

They are vitamin A (retinoic acid) and its natural (retinol, retinaldehyde), and synthetic derivatives. They easily penetrate the skin and are clinically proven to increase collagen synthesis. For sure, I will discuss these in upcoming posts. 🙂

Topical Vitamin C

L-ascorbic acid and vitamin C derivatives

Vitamin C is essential for collagen formation by fibroblasts. It also appears crucial to keep low levels of environmentally-induced free radicals in the epidermis. That may be why the epidermis stores high amounts of L-ascorbic acid.

The only form of vitamin C scientifically proven to penetrate the skin and provide it with extra antioxidant protection when topically applied is L-ascorbic acid. Yet, it is challenging to formulate in such a way that it penetrates the skin. Moreover, it is unstable and thus oxidizes readily upon contact with air, light, or certain skincare ingredients (becoming brownish).

There are some more stable topical vitamin C derivatives out there (magnesium ascorbyl phosphate, tetrahexyldecyl ascorbate, 3-o-ethyl ascorbic acid, etc.). However, there are not enough scientific, proper data to support their efficacy (they do not compare with L-ascorbic acid).

But let’s get practical and analyze some skincare products that illustrate those challenges!

Examples of topical vitamin C products: do they work?

The effective concentration of topical L-ascorbic acid is 10-20%. Yet, the main concerns with L-ascorbic acid are:

· its low stability (and high probability of degradation upon undesired interactions with other molecules, such as active ingredients or fragrances)

· its challenging penetration (it is a water-loving, charged molecule that requires to be at a low pH of 3.5 or less)

· its chances of causing skin irritation (experienced by many due to low stability and low pH).

Product 1: Skinceuticals C E Ferulic

SkinCeuticals (part of L’Oréal) owns the patent that demonstrates the activity of topical L-ascorbic acid. The topical formulation must contain small percentages of ferulic acid (critical for low pH) and vitamin E (grants stability), and specific solvents.

Ingredient list: Aqua/Water, Dipropylene Glycol, Ascorbic Acid, Glycerin, Laureth-23, Phenoxyethanol, Tocopherol, Ferulic Acid, Sodium Hyaluronate, FIL D31590/4.

As specified on its packaging, this product contains 15% ascorbic acid, 1% vitamin E, and 0.5% ferulic acid. That guarantees an adequate pH. Additionally, it lacks fragrance, which avoids additional stability issues.

This product would be the standard against which to compare any other formula (at least for now).

Product 2: Vichy LiftActiv Specialist Peptide-C Anti-Ageing Ampoules

Also by L’Oréal, yet very different from the product above in terms of proven efficacy.

Ingredient list: Aqua/Water, Ascorbic Acid, Butylene Glycol, Dipropylene Glycol, Glycerin, Sodium Hyaluronate, Hydrolyzed Rice Protein, Hydrolyzed Hyaluronic Acid, Hydrolyzed Lupine Protein, Pentylene Glycol.

It contains 10% of ascorbic acid (as seen on the packaging), thus an effective percentage. But it lacks vitamin E and ferulic acid: then how do we know that ascorbic acid is at an appropriate pH?

It has various humectants (such as hyaluronic acid) that provide moisture and, maybe, aid in ascorbic acid penetration. An advantageous feature is that it also lacks fragrance.

Product 3: Endocare C Proteoglycans Oil-free Ampoules

Ingredient list: Aqua. Propylene glycol. Snail secretion filtrate. Butylene glycol. 3-O-ethyl ascorbic acid. Dimethyl isosorbide. Ascorbic acid. Polysorbate 20. Glycosaminoglycans. Sodium hyaluronate. Trisodium ethylenediamine disuccinate. Sodium hydroxide. Tocopheryl acetate. Phenoxyethanol. Benzoic acid. Dehydroacetic acid. Parfum.

This product contains 15% of vitamin C (as seen in the packaging); thus, it could be efficacious. However, there are two different forms of vitamin C:

– in the first place (in a higher percentage), there is 3-o-ethyl ascorbic acid, a vitamin C derivative not clear to be converted in L-ascorbic acid in the skin. But it might be a good antioxidant for the formulation (to prevent it from getting ruined).

-second, there is ascorbic acid. But what about its percentage? Is it at least 10% and thus efficacious? It doesn’t seem to be like that (in the best case, it would be 7.5%).

It also has vitamin E (tocopheryl acetate). But lacks ferulic acid: we don’t know whether the formula has a proper pH. It contains humectants (such as glycosaminoglycans, sodium hyaluronate). They might aid in penetration. Finally, it features fragrance (parfum) which may not favor ascorbic acid stability.

Among those three, which product would you choose?

It is obvious. Right?

Another thing to recall is that some people experience non-permanent orange discoloration in the skin with any vitamin C topical product. That suggests that at least part of the topically applied vitamin C might oxidize readily upon application and probably become unable to perform any activity.

In short, the penetration and activity of L-ascorbic acid in deep layers of the skin (such as the dermis) remains controversial even with the best topical product. Therefore, it seems unlikely that topically applied vitamin C may induce significant collagen production in the dermis. In the best-case scenario, it appears it could provide the superficial layers of the skin with some free radicals scavenging activity.

Furthermore, when the levels of vitamin C in the blood and skin are high enough, it seems that topical L-ascorbic acid cannot boost collagen production. Maybe not even an antioxidant action.

Therefore, wouldn’t it be better to invest in ingesting enough vitamin C? Perhaps raise its dose when, for instance, we get increased sun exposure? Maybe, introduce other, more stable topical antioxidants in our skincare routine, such as vitamin B3 (to check my latest post on it click here).

What do you think? I’d love to hear about your experience with topical vitamin C products. So please comment below!

I hope you liked this post.

Please let me know if you have any questions about any of the topics discussed above. I will answer them and take them into account for upcoming posts!

See you soon!

María

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