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“The best wrinkle is the one you will never get.” (Dr. Muller)

It would be nice to stay young forever and have perfect skin at any age, right? But, why can’t we? In this article, I will talk about skin aging, the importance of collagen, and whether or not using collagen creams and supplements is beneficial for the health of your skin.

Why does skin age?

Unfortunately aging is a natural phenomenon that cannot be reversed. Skin aging can be caused by both internal and external factors. Intrinsic aging is a physiological process that leads to thin, dry skin, and fine wrinkles, while extrinsic aging is caused by external environment factors such as air pollution, poor nutrition, smoking, stress, and sun exposure, resulting in coarse wrinkles, loss of elasticity, and rough-textured appearance. These aging process are accompanied by structural and functional changes in extracellular matrix components such as collagen, elastin, and hyaluronic acid that are required for strength, elasticity and hydration of the skin (1).

What is collagen?

Naturally produced by our body, collagen is a main component of connective tissue. It is the most abundant protein in mammals and represents 25-35% of the whole-body protein and 75-80% of our skin. In addition, collagen is found in bones, tendons, blood vessels, ligaments, cartilage, and muscles.

What happens to collagen as we age?

As we age, our body starts producing less collagen and skin becomes thinner, drier, and less elastic, which leads to wrinkle formation. The biggest changes typically occur when people are in their 40s and 50s, but they can begin as early as the mid-30s. Although aging is a natural process, as I mentioned above external factors such as UV exposure, and poor diet can speed it up. Since collagen is present in many organs, you can imagine that collagen loss can affect other parts of the body. For example, bones become fragile and joint cartilage begins to wear out making movements and daily activities more and more difficult (2).

Given the importance of collagen in skin health, it’s not surprising that it has become the target of food and beauty industry as a way to delay aging. The question is whether or not adding collagen to our daily life can affect the aging process.


In recent years, collagen has become a real MUST HAVE ingredient in cosmetic formulations. Is it effective? Well, collagen is a huge molecule (~300 kDa) and it cannot be absorbed into the dermis through small pores of the skin. When applied topically, it sits on the surface of the epidermis (the outer layer of the skin) and as such, it prevents water loss and keeps the skin hydrated. It can also protect the skin from the aggression of external agents, however, it cannot contribute to the synthesis and formation of the triplex collagen. To get around the sizing issue, most creams and lotions contains hydrolyzed collagen or collagen peptides. Hydrolyzed collagen is a group of peptides with low molecular weight (3–6 kDa) that is obtained by breaking down the native collagen protein into small peptides through an enzymatic reaction in acid or alkaline media at a specific incubation temperature (3,4). Topical application of 10% hydrolyzed collagen face mask is reported to increase skin moisture content and elasticity after 30 days suggesting that collagen peptides can penetrate efficiently into the stratum corneum (the outer layer of the epidermis) (4). The study, however, falls short of showing that if these collagen peptides can make their way into the dermis and increase collagen production down the line. In mice,  it’s been suggested that collagen peptides can cross the epidermis barrier, make their way into the dermis and activate collagen synthesis (5). However, it is a bit of stretch to assume the same scenario in humans and the reason is the difference between mouse and human in terms of skin structure. Mouse epidermis generally comprises only three cell layers and is <25 m in thickness, whereas human epidermis commonly constitutes 6–10 cell layers and is >50 m thick. Thus, It’s not abundantly clear whether or not topical collagen peptides can help rebuild new collagen in human dermis.


Like all other proteins, when collagen is consumed, it will be broken down to smaller polypeptide units, pass through our intestinal barriers and into our bloodstream. In essence, collagen won’t be called “collagen” anymore and body won’t know that “collagen” is consumed. In theory, body utilize absorbed collagen peptides in areas that need repair the most, and hopefully our skin would be one of them. There are plenty of reports providing evidence that oral ingestion of collagen peptides makes the skin softer and provides enhanced textural properties (4). In mice, collagen peptides are reported to improve the skin laxity,  repair collagen fibers, and increase collagen content both quantitatively and qualitatively (5,6). Similar results have been reported in humans. In one study, for example, 72 healthy women aged 35 and older were asked to consume a product containing collagen peptides, vitamin C, acerola fruit extract, zinc, biotin, and a native vitamin E complex. After 12 weeks, there was an improvement in skin hydration, elasticity, roughness, and density (7). Although these results are promising, I have to explain a couple of points:

1) In many of these studies, the selected age rage is around the younger side of the spectrum (35 years old) as opposed to the older skin and it’s not abundantly clear how many of participants are in their 30s, 40s, or 50s. We know that collagen supplements have a far better results on younger skin than the older one because the younger skin has a better starting point. In other words, if 60 out of 72 participants are in the 30s and early 40s, the effect of collagen supplement would be much better than a older group where 60 of 72 participants are in their 50s. Does it make sense? So, without knowing the exact age of the participants, it would be difficult to accurately evaluate the effect of collagen supplements on skin health.

2) In some of these studies, the regimen included strong antioxidants like vitamin C, vitamin E, and acerola fruit extract. Although antioxidants are essential for collagen synthesis, they are also involved in reducing collagen degradation, scavenging free radicals, and lowering skin inflammation (8). So, it would be logical to conclude that not all of the skin improvements in these studies are due to collagen production. In fact, if it was that simple, we should have been able to turn back the clock and make a 50-year-old skin to look decades younger. So, it seems that other factors also play a role in collagen regeneration and synthesis.

Bottomline,  if you like your skin care routine or enjoy the perceived benefits of collagen supplements and aren’t experiencing any negative side effects, Keep it up by all means. Collagen may also support joint and bone health. Remember to drink plenty of water, eat foods high in antioxidants, and stay away from stress.


I hope you have found this article useful. Feel free to contact me at motahariz@zinnianatural.com if you have any questions.

Stay Amazing, Stay Beautiful!

Dr. Zahra Motahari


References :

  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6047276/
  2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1606623/
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6891674/
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7070905/
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5707681/
  6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2896882/
  7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6835901/
  8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3583892/



  1. Gorgia says:

    Very informative, thank you!

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