Collagen + Aging Explained: Myths, Claims and Facts

by Marie Veronique

The role of collagen and its importance in maintaining beautiful skin is a topic that’s been dominating beauty news recently, no doubt because of the zillions of new treatments purporting to enhance collagen production and give your skin a smooth, youthful glow. Here, we examine the trendiest: collagen peptides applied topically, collagen peptides ingested and “collagen-induction” via microneedling.

Kristina and I generally run counter to popular thinking, but don’t worry—where we disagree we have suggestions that really work, based on genuine research in the lab and in the field.

But let's begin with the basics. What is collagen and why is it so crucial?

What is collagen?

“Collagen is the body’s most abundant protein…[it] accounts for three quarters of the dry weight of skin, and is the most prevalent component of the extracellular matrix.” [1] The extracellular matrix, or ECM, is a gel-like matrix composed of polysaccharides and proteins that provides structural and biochemical support to the surrounding cells.

It’s also what gives skin a plump, youthful, healthy glow. Think of very young skin as a new mattress: its smooth surface, supported by coils and a fibrous underpinning, promises resilience and bounce. Skin is supported by an underlying matrix of collagen and elastin fibers, held in place by gel-like polysaccharides such as hyaluronic acid. Just like the pillow top on our mattress, the epidermis layered over the support structure, in its youthful phase, presents a smooth and even surface to the world. But much like mattresses, as the skin ages its support structures weaken, and formerly smooth surfaces develop creases.

Fortunately, our skin is renewable. Infinitely clever Mother Nature has provided us with interconnecting repair systems that work to keep skin’s supporting structures in good shape—Extra Cellular Matrix (ECM) components like collagen and elastin undergo cycles of breakdown and renewal in much the same way that your skin cells renew themselves on a regular schedule.

Given that collagen constitutes three quarters of the skin, we clearly need to keep making the stuff, and in plentiful amounts. Most of the skin’s repair activities take place in the dermis, and collagen production is one of the busiest departments in the bustling dermal maintenance and renewal factory. Fibroblast workers tirelessly crank out new collagen while enzyme workers break down old collagen and carry it away. Everything hums along nicely…until you reach age 35 or so. (It can be earlier if you’ve been exposed to a lot of sun or pollution). Suddenly, your fibroblasts begin to tire and slack off, calling in sick more often and just generally not performing as well. In the meantime, enzymes, encouraged by oxidative stress, start working overtime, just when you’d rather they stayed at home.

It’s very important to remember that collagen synthesis proceeds according to your body’s schedule, and production slow-down is a natural feature of aging. To remedy collagen depletion, your best option is to boost collagen production at the fibroblast level; you can’t stockpile collagen against future shortages as it exists in finite amounts in the skin. You can, however, ensure that the your production schedule is on track, with production of new collagen matching breakdown and removal of old.

When the skin stops bouncing back

Make a face and you create expression lines. Young skin bounces back—you can make faces all day long but it reverts to plump smoothness when you stop because an abundance of collagen is keeping its surface strong and resilient.

Then one morning you look in the mirror and notice that you’ve got a wrinkle or two. (Or three.) First you may notice fine lines around the eyes, or maybe the marionette lines from nostril to mouth. This is because your collagen has become less abundant, and the fibers are weaker due to oxidative stress as well as everyday wear-and-tear. (Who knew your computer scowl would come back to haunt you?)

And then comes the day when those lines remain long after you’ve ceased making that face, because there’s not enough collagen to fill in the grooves. What you have to look forward to from there, in addition to more wrinkles and lines, is sagging, because as skin density decreases, so does tensile strength and, thus, its ability to resist gravity. In short, your skin loses its ability to bounce back.

No wonder collagen has occupied so much of the beauty space lately. So, let’s take a look at some of the treatments Kristina and I have been getting so many questions about.

Claim 1: Peptides applied topically build collagen in the skin

One question on everyone’s lips seems to be, should collagen peptides be part of my proactive skin care routine or are they more hype than help?

Peptide Types, what works, what doesn't?

There are actually two different peptide types on the market: signal peptides and collagen hydrolysates, aka collagen peptides. Neuro or signal peptides have been around for a few decades; the synthesized amino acid chains are designed, just like their natural counterparts, to act as cell messengers--instructing, for example, fibroblast cells to build more collagen.

However, signal peptides are too frangible to penetrate the skin at the level where the signals need to be sent; they are protein fragments, and not at all stable. Even assuming a synthetic peptide could reach its destination, the chances that it would get there intact and prepared to deliver the correct message are very slim. It’s much more likely that the peptide fragment would fragment even further, so that even if it reached its destination, it would be sending the wrong message.

So does this type of peptide work? Not likely.

Collagen peptides

Collagen hydrolysates or peptides (the new kids on the block) applied topically would appear to be a more promising route. They are produced from collagen found in the bones, skin and connective tissue of animals by a process called hydrolysis. This process breaks down the molecular bonds between individual collagen strands using combinations of physical, chemical or biological means. The amino acid content of hydrolyzed collagen is the same as collagen. Hydrolyzed collagen contains 19 amino acids, predominantly glycine, proline and hydroxyproline, which together represent around 50% of the total amino acid content.

Does this type of peptide work? Maybe... to some extent.

But there’s another problem. While some studies suggest that collagen hydrolysates or peptides applied topically may help to rebuild collagen, we wonder: from what source, and how do we administer them? Delivery system is everything, and Kristina and I are unsure of the bioavailability of collagen peptides applied topically, no matter how small. It’s a long road from applying collagen peptides topically to increasing either collagen volume or collagen production in the dermis. Preliminary studies on mice and in vitro may be exciting, but signal peptides showed initial promise that didn’t pan out.

Barrier Restore Serum contains collagen peptides in the form of hydrolyzed collagen. The rationale was to supply certain amino acids key to creating a functional stratum corneum. Our position on collagen peptides—as of this moment—is that even if they penetrate no further than the stratum corneum, they are useful. It’s possible that the few studies showing benefits may be recording changes at the SC level, rather than more deeply. In any case, claims that collagen peptides applied topically will increase collagen production in the dermis is a huge leap, and one that the jury is still out on.

A topical alternative that is proven to work

In contrast to signal peptides and collagen hydrolysates, retinoic acid and retinol have 40 years of studies supporting their efficacy. Retinoic acid is a genuine cell signaller—it works by attaching to retinoic acid receptors on fibroblasts, directing them to produce more collagen (among many other things). One of many retinol studies showed that “a four-week treatment with 0.1% retinol increased levels of procollagen types 1 and 3 and reduced wrinkles after 12 weeks.”[2]

The importance of vitamins A + C

Retinol sends a signal to the fibroblast to make more collagen, but vitamin C is the rate-limiting step in the biosynthesis of collagen—meaning it must be present in skin tissue for that command to be carried out. Furthermore, in an example of synergy, researcher Dr. Seite and colleagues found that “repeated topical application of a preparation containing both retinol and vitamin C could reverse, at least in part, skin changes induced by both chronological and photoaging.”[3]

Retinol vs. peptides: the bigger picture

When it comes to stimulating collagen production, synthesized signal peptides and retinol take completely different paths: short chain signal peptides send repair messages to fibroblasts in an emergency, while retinoic acid attaches to retinoic acid receptors (RARs) on fibroblasts, instructing them to perform a number of tasks.

Skin is composed of numerous components that work within sets of processes and systems. One unit getting a “mixed message” could disrupt the orderly progression of production all the way down the line. Retinol works via a different process than signal peptides. Palmitoyl pentapeptide-4, a five chain amino acid signal peptide, sends a message to the fibroblast to make more skin cells in response to skin damage. Retinol converts to retinoic acid, then sends numerous messages to retinoic acid receptors on fibroblasts specifically designed to receive a variety of messages—make more skin cells, make more collagen, induce collagen breakdown, normalize skin cell development, regulate sebum, etc.

This may present another problem for signal peptide technology: the whole repair process involving breakdown of old material to replace it with new is disrupted. Even in the unlikely event that you can stimulate collagen production, to do so without taking into account the other half of the process—the breakdown and removal of old and damaged collagen—might upset the natural balance of collagen levels, with unforeseen consequences...such as buildup of aged, brittle collagen fibers that prevents replacement by newer collagen, which might in turn lead to development of unhealthy elastotic material.

Claim 2: Ingestible collagen peptide supplements build collagen in the skin

Hydrolyzed collagen supplements come in many forms; some contain the collagen types I and III which are known for restoring skin firmness and elasticity.

  1. Bovine (beef) collagen is made of mostly types I and III collagen.
  2. Fish collagen provides mostly type I collagen, with the amino acids glycine, proline and hydroxyproline in abundance. Hydroxyproline is needed for collagen stability and is created by modifying normal proline amino acids after the collagen chain is built. This reaction also requires vitamin C (to assist in the addition of oxygen), which is why vitamin C deficiency can cause abnormalities in collagen levels.
  3. Type II collagen from chicken has been demonstrated to reduce joint problems associated with arthritis, but its impact on skin is negligible.

There are some problems associated with collagen supplements.

  1. Contamination: if you take supplements, make sure to buy only those that have been tested for heavy metal contamination. 
  2. Efficacy: peptides undergo changes as they pass through the gastrointestinal tract. Some doctors suggest that their lower pH may render them almost useless.

The important thing to remember is that it’s all in the translation. Applying collagen to the skin’s surface or swallowing collagen supplements does not necessarily translate into more collagen in the dermis. In fact, so much happens to impede this progression that the likelihood of its getting that far, intact and in a usable form, is quite small.

An internal supplement that works

However, there is a tried and true way to get what you need: just ask nature. Food comes in digestible packages that are designed by nature to give you everything you need in the appropriate amounts. No guesswork, no fuss. Supplements simply don’t do that.

To build collagen, Kristina suggests eating soups made with bone broth (eating meat on the bone such as a chicken leg vs a chicken breast has similar benefits). Along with plentiful amounts of collagen, this provides other necessary minerals like zinc and calcium, as well as a generous helping of hyaluronic acid. I suggest eating fish, especially fatty fish like sardines, mackerel and salmon, two to three times a week. This is not only an excellent source of protein; it also comes with a necessary helping of omega-3 essential fatty acids of the eicosapentaenoic acid (EPA) type. One study on EPA found that “eicosapentaenoic acid (EPA) was found to inhibit UV-induced matrix metalloproteinase-1 (MMP-1) expression in human dermal fibroblasts.” [4] In other words, the enzyme MMP-1 that works overtime to break down collagen is inhibited by EPA.

Claim 3: Collagen induction (AKA microneedling) builds collagen in the skin

Hardly a day goes by that I don’t get a question about microneedling. Should I do it? Will it help? Will it hurt? Much like microdermabrasion, microneedling is the latest variant on the skin wounding principle. As the procedure has been described to me, tiny needles deliver controlled wounds to the skin. If you add serums to the procedure, they will infuse more deeply into the skin, making them more effective. Dr. Bowe observes that “Up to eighty percent of a product can penetrate skin directly after microneedling, compared to a mere 7% with normal application on intact skin.” [5]

This all sounds great—except, perhaps, that part about tiny needles delivering controlled wounds to the skin. Ouch! There have, of course, been attempts to create these same effects without having to actually injure the skin. Damaging the skin’s surface sends a specific signal pentapeptide scurrying to fibroblasts with the message that they need to start making more collagen and skin cells. We discussed earlier how a specific pentapeptide was attached to a fatty acid to become palmitoyl pentapeptide-3, (later -4 after a molecular structure correction). The idea was that this oil soluble version would penetrate to the dermal level where fibroblasts reside and deliver an emergency “make more collagen” message, without wounding the skin. Then, when this synthesized peptide stimulated fibroblasts in test tubes to produce components of the ECM—collagen, elastin and hyaluronic acid—researchers got very excited.

Unfortunately, the promise at the in vitro level did not make it all the way to in vivo testing; that is, similar results on actual humans were not reproducible. Unless more convincing clinical data comes in, signal peptide serums will probably continue to lose ground to research-supported ingredients and methods that deliver significant improvement over time.

In moderation, it’s promising

Your skin works hard to heal itself after you’ve injured it, and microneedling does have supporting data: “a recent study showed that microneedling can increase epidermal thickness by a whopping 140 percent while also increasing and thickening collagen bundles in the dermis.” [6] I suspect that microneedling works because the signal pentapeptide actually gets to fibroblasts to deliver the message.

If your intent is to minimize acne scars, or maybe do a little turnaround on photoaging damage, then this procedure may be for you--but probably no more than once every few months. Remember, your body makes its own collagen (as well as new skin cells, hyaluronic acid and all those good things) on a regular schedule, as long as you supply it with the necessary building materials.


  1. If you decide to do it, ask for a serum containing stabilized ascorbic acid as part of the delivery system—remember the rule, no vitamin C, no collagen production. (Use only serums with stabilized vitamin C; never use ascorbic acid powders as they can seriously damage skin.)
  2. Think of microneedling as a once-in-awhile boost to your collagen production schedule. If you ask your fibroblasts to do too much overtime, you may end up doing more harm than good in the long run.
  3. If you’re dealing with an inflammatory issue like acne or rosacea, or a barrier malfunction problem presenting as some type of dermatitis, you might want to choose another procedure because microneedling could increase inflammation in the skin. Or, perhaps, try topicals that improve barrier function, contain micronutrients like vitamins A and C that stimulate collagen production, or that balance the microbiome.

Some microbial alternatives

Some of the latest research on skin helpers of the microbial persuasion is quite promising.

  • People taking Lactobacillus plantarum orally “had a significant reduction in wrinkle depth at week 12…and skin elasticity in the probiotic group improved by 13.17% (p < 0.05 vs. controls) after 4 weeks and by 21.73% (p < 0.01 vs. controls) after 12 weeks. [7]
  • Bifidobacterium appear to prevent UV damage to skin, while the Lactobacilli help to subdue inflammation, prevent water loss, diminish acne and improve barrier function.
  • Streptococcus thermophilus gets my vote for hero microbe. It stimulates ceramide protection in the skin and thus helps with barrier function. [8]

Our Tips for Increasing Collagen


Feel free to try the new products and procedures if they appeal to you, but we encourage you to try KH + MV products, particularly Barrier Lipid Complex, Soothing B3 Serum and Barrier Restore Serum as well. Here is a way to incorporate them, along with the collagen boosting standards Vitamins C + E + Ferulic Serum and Gentle Retinol Night Serum (retinol w/ vitamin C), into your regular routine:

  • Morning: Soothing B3 Serum, Vitamins C + E + Ferulic Serum, Barrier Restore Serum, zinc oxide only sunscreen.
  • Evening: Soothing B3 Serum, Gentle Retinol Night Serum, Barrier Restore Serum, Barrier Lipid Complex.


  • Bone broth every evening, if possible.
  • Oily fish 2-3x a week.
  • Vegetables rich in vitamin C and E: Sources include dark green vegetables, citrus, strawberries, melon, tomato, potato, peppers, parsley, sunflower seeds, hazelnuts, and almonds.


  • Probiotics
  • Vitamins C, E, D


  • Sunscreen SPF 20 every day; SPF 30 for beach, outdoors, sports etc. (Zinc oxide only)

If you want to avoid severe collagen loss you need to wear sunscreen every day, as “...histological studies suggest a large loss of collagen in the dermis of chronically sun-damaged skin.” The damage appears to result in total collagen loss of about 20%, with a 40% decrease of type III procollagen. An “accumulation of an elastotic material...appears to replace collagen.” [9]

I adore our Mother Nature. No matter what we get up to, she still steps in to try and repair the damage. Let’s give her what she needs so she’s not forced to replace collagen with “elastotic material” which I envision as a sort of a rubber-band like substance. We owe it to her—and to our skin.



  1. ^ The Beauty of Dirty Skin, Whitney Bowe, MD, Little, Brown and Co., 2018, p.71
  2. ^ Retinoids in the treatment of skin aging: an overview of clinical efficacy and safety, Mukherjee, S. et al,
  3. ^ Histological evaluation of a topically applied Retinol-Vitamin C combination. Seité S, Bredoux C, Compan D, et al. Skin Pharmacol Physiol. 2005;18:81–7.
  4. ^ Photoprotective and anti-skin-aging effects of eicosapentaenoic acid in human skin in vivo. Kim HH, et al.
  5. ^ Ibid, Bowe, Whitney, p. 180
  6. ^ Op. cit., Bowe, p.179
  7. ^ Clinical Evidence of Effects of Lactobacillus plantarum HY7714 on Skin Aging: A Randomized, Double Blind, Placebo-Controlled Study, Dong Eun Lee, et. al. J. Microbiol. Biotechnol. (2015), 25(12), 2160–2168
  8. ^ Increase of skin-ceramide levels in aged subjects following a short-term topical application of bacterial sphingomyelinase from Streptococcus thermophilus. Di Marzio, et al. Int J Immunopathol Pharmacol. 2008 Jan-Mar;21(1):137-43.
  9. ^ Collagen alterations in chronically sun-damaged human skin, Schwartz E. et al, Photochem Photobiol. 1993 Dec;58(6):841-4

