As the body’s largest organ, skin plays a critical role in our protection, regulation, and sensation. Skin is the body’s first defense against the external world, shielding us from harmful environmental factors such as UV rays, pollution, pathogens, and physical dangers. Skin also plays a critical role in maintaining homeostasis, including water retention, temperature regulation, and vitamin synthesis. And, of great importance to our survival, skin provides our bodies with sensations required to make key instinctual decisions.

But what ages skin? As our cells naturally age and are exposed to daily harsh elements, skin can accumulate damage at the cellular level. These intrinsic and extrinsic aging factors cause skin to deteriorate and become less effective at performing its crucial protective, regulatory, and sensory functions. Visually, these effects can be observed by a loss in skin strength, texture, and tone – All physical signs of extrinsic or intrinsic aging should not be taken lightly, as they can point to an underlying loss of skin health and function.
So how do we identify skin aging and can we take steps to slow down this process? This blog will discuss what happens to a person's skin as they age, including the signs of aging skin and factors that can accelerate or hinder the process of skin aging.A characteristic feature of older skin is the progressive loss of the primary structural and functional proteins in the skin: collagen and elastin. Collagen promotes skin firmness while elastin enables skin rebound and elasticity, and these proteins work in concert to enable skin resilience and provide a fresh, smooth appearance. While the production of these essential structural proteins naturally decline with age¹, especially during menopause², the rate of decline with age can be greatly accelerated by both internal and environmental stressors, such as UV exposure, mental stress, poor diet, and smoking³. When skin cells are broken down from these stressors, the fragmented proteins can accumulate in the skin and inhibit the ability of skin cells to regenerate new collagen and elastin¹.Older skin also exhibits reduced moisture retention due to loss in structural integrity and lower production of moisture-retaining molecules. One such molecule is hyaluronic acid, an essential compound produced in the skin that has a uniquely robust capacity to bind and retain water in the skin. Like collagen and elastin, production of hyaluronic acid significantly reduces with age and as a result of damage accumulation. Declining levels of hydrating molecules like hyaluronic acid in the skin can lead to compromised skin structure and barrier function⁴.Additional age-associated changes in skin can also be attributed to the loss of fat, cartilage, and bone structure in the layers below the skin, particularly the chin, cheeks, eyes, and nose. This may result in sunken eyes, loose skin, and puckering areas. These physical effects can be exacerbated by excess weight loss or gain, facial movements, sleeping position, and gravity.While there are numerous signs of skin aging, here are a few of the most common:The structural integrity of the skin layers often becomes compromised with age due to the flattening and thinning of layers between the dermis and epidermis. This is caused by the loss of mass in the fat pad beneath the skin’s surface. This subsequent fragility, as well as the thinning of blood vessel walls, can result in easy bruising and development of skin damage, lesions, and skin cancer⁵.Elasticity in the skin is reduced with age due to the degradation of structural proteins, especially elastin and collagen. Skin thickness and cell turnover also decreases by approximately 6% per decade⁵. This can lead to loosely-hanging skin, reduced facial structure, less effective moisture retention, and increased presence of fine lines and wrinkles.As skin ages, it loses the ability to maintain robust skin cell shape and efficient regeneration. This is especially true for pigment-producing cells called melanocytes. Melanocytes decrease by up to 20% per decade, contributing to uneven pigmentation with age. Reduced cellular turnover leads to thinning of the skin and loss of facial tone, which can cause transparency⁶.Aside from lines and wrinkles, most of these deleterious changes alter the structure and biochemistry of the skin that affect injury repair, permeability, texture, and prevalence of skin disease.

Thinning skin or presence of crepey skin is another key indicator of skin aging. Crepiness is caused by the decrease in epidermal thickness that comes with age and is particularly common in women on the face, neck, chest, and forearms⁵. Skin’s strength and elasticity is also reduced in aging and is accelerated with extreme sun damage, which can cause a weather-beaten appearance called elastosis⁷.

Significant pigmentation or color changes, including skin paling and transparency, is another key indication of aging. The combination of skin thinning and a decrease in the number of pigment-producing melanocytes can cause significant changes in skin tone that are commonly observed with age. Sun-exposed areas are especially prone to skin changes like pigmentation, including the development of lentigo maligna or “liver spots.”

Finally, aged skin is often very dry due to the low production of hyaluronic acid and the decreased production of facial sebum–a combination of oily lipids produced in the follicles to protect the skin's surface. Women gradually produce less sebum beginning after menopause through the age of 70, while men tend to produce less sebum after the age of 80⁸.The best known way to slow the effects of skin aging are with physical protection from UV rays and environmental irritants. Regular, year-round application of at least 30 SPF sun protection and avoiding tanning/sun exposure can help protect your skin at the cellular level from harmful UVA and UVB rays that greatly accelerate the skin aging process.Stress, lack of sleep, and poor diet also have profound negative impacts on skin health due to their disruption of cellular growth and regeneration⁹. Proper rest and a healthy lifestyle promote skin cell maintenance. A diet with plenty of greens, grains, and lean protein can ensure proper levels of vitamins, trace elements, water, and peptides, all of which contribute to optimal functioning skin cells¹⁰.Maintaining proper moisture levels with the regular use of topical skin care products, such as a gentle gel cleanser and peptide moisturizer can also promote healthy cell function. Adequate moisture retention helps promote proper skin cell performance and turnover, and clean skin ensures removal of dead skin cells that can inhibit product efficacy. Staying consistent with a specifically curated skin care regimen for aging skin that includes a gentle cleanser and a hydrating moisturizer, especially in drier climates and during the winter months, can combat excessive dryness and undue skin damage.

Certain medications and tobacco use can cause premature aging in the skin due to decreased collagen synthesis and should be avoided whenever possible.Skin begins to thin when collagen levels decrease. Though the age at which collagen levels start to decline is based on skin type and varies from person to person, , this decline can begin as early as your twenties. On average, collagen production peaks in your late 20’s to early 30’s, with a gradual decline occurring throughout life¹¹. However, other external factors, such as increased sun exposure and lifestyle choices, could cause earlier skin thinning.There are several methods to evaluate skin elasticity, which measure the ability of the skin to return to its original position. A common and easy method is the “Snap Test,” which can be performed by lightly pulling the skin underneath the eyes and observing how quickly it snaps back. Healthy skin snaps back immediately, while dehydrated or less elastic skin will take longer to return to its normal position. Similarly, the “Pinch Test” can be performed by pinching the skin on your arms, cheeks, and abdomen, with slowly-returning skin indicating a loss of elasticity.

Close inspection of your skin in the mirror can also help identify loss of elasticity. Areas with recent changes in color, transparency, or firmness may be indications of aging skin. The presence of fine lines and wrinkles in the face and eyes are also obvious indications.Skin and longevity scientists have recently investigated the molecular causes of skin aging and identified ways to target and improve skin elasticity. In particular, the researchers at OneSkin have developed a peptide called OS-01 that is scientifically validated to promote the activity of key genes associated with elastin, collagen, and hyaluronic acid production in lab-grown ex vivo human skin models. The OS-01 peptide has also been scientifically validated to aid in cellular repair from damage caused by UV radiation and increase skin’s epidermal thickness in lab-grown ex vivo human skin models.

• Our skin has tremendous protective and homeostatic capabilities that progressively wane due to damage and natural degradation during aging.
• Collagen and elastin within the skin barrier provide strength, elasticity, and texture but can be compromised due to external exposures such as UV rays, pollution, pathogens, and physical dangers.
• A compromised skin barrier and changes to the underlying fat and bone can reduce the skin’s function and structure, ultimately leading to dry and fragile skin with a saggy, transparent appearance.
• Skin aging can be delayed by the use of sun protection, a healthy diet, a proper cleaning and moisturizing regimen, and other lifestyle adjustments.
• Additionally, scientists at OneSkin have developed a novel peptide, which is scientifically validated to reverse the effects of aging in the skin at the cellular level. The OS-01 peptide is able to promote the production of collagen, elastin, and hyaluronic acid (shown in lab-grown ex vivo human skin models) to improve skin texture, thickness, and reduced visibility of lines and wrinkles.

Sources:

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1606623/
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7859014/
3. https://www.mdpi.com/2079-9284/5/1/14
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3583886/
5. https://pubmed.ncbi.nlm.nih.gov/16221138/
6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3840548/
7. https://pubmed.ncbi.nlm.nih.gov/30052192/
8. https://link.springer.com/referenceworkentry/10.1007/978-3-662-47398-6_4
9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7146365/
10. https://pubmed.ncbi.nlm.nih.gov/27144559/
11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1151092/