Decoding the Connections Between Intrinsic & Extrinsic Aging

Reference Lab

JAN 17, 2023

You’ve heard it before: aging is inevitable. But have you ever stopped to consider how true that statement really is? It turns out, it’s only half true and breakthroughs in longevity science–including our OS-01 peptide–are making it less true with every passing day. In fact, there are two major types of aging: intrinsic and extrinsic aging. While one is mostly out of our control, the other is almost entirely preventable. Let’s take a closer look at the two types of aging and what we can all do to help our bodies grow older in good health.

Have you ever looked around at your family and noticed some similarities in the way you age? Maybe it’s matching lines around the eyes. Maybe you look at old pictures of your mom or dad and see your own face. What you’re seeing might be more than family resemblance: it could also be physical signs of intrinsic aging. Determined largely by your genetics, intrinsic aging is the predetermined process that your body will undergo over time based on its innate ability to repair damage.

Extrinsic aging is just the opposite: externally modulated aging that occurs as a result of preventable environmental and lifestyle factors. The vast majority of extrinsic aging is a result of UV exposure, but other external factors related to lifestyle like smoking cigarettes or eating a diet high in processed foods also contribute to the acceleration of extrinsic aging. These external aging factors exacerbate intrinsic aging by increasing the rate at which we age.¹ At the heart of both types of aging is cellular senescence: one of the nine hallmarks of aging that longevity scientists now know is central to the aging process. Occurring continuously within our bodies from the moment we are born, senescence is the end stage in a cell’s life cycle when it stops dividing. When we’re young and healthy, senescent skin cells are quickly cleared away and replaced with new cells. But as we get older, more and more senescent cells accumulate. When these senescent skin cells linger, they secrete biochemical signals that induce chronic inflammation, suppress the immune system, and drive neighboring cells into senescence.

Cellular senescence is one of the root causes of genetically programmed intrinsic aging. Preventable extrinsic aging just makes things worse: factors like UV exposure exacerbate the rate of cellular senescence, making it more difficult for our bodies to keep up with the task of repairing damage. When our bodies can no longer repair damage caused by both intrinsic and extrinsic aging factors, it can have systemic impacts–from skin damage to age-related diseases like Alzheimer’s. So how do you know if what you’re seeing in the mirror is a sign of intrinsic aging vs extrinsic aging? To answer that question, scientists have compared the way photoprotected skin–think skin that’s either regularly treated with sunscreen or covered with clothing–ages in comparison to skin that’s been regularly exposed to the sun’s UV rays over a lifetime.

Photoprotected skin, which is primarily subject to intrinsic aging, shows signs of aging mostly at the basal layer–one of the deeper layers of the skin. These signs include diminished cell production in the basal layer, which results in a thinner epidermal layer. Other signs of aging skin include reduced collagen production, lower elastin levels, and diminished levels of oligosaccharide, a substance that helps the skin maintain optimal hydration levels. Visibly, these cellular changes show up as thinner, more fragile skin with dryness, loss of firmness, and fine lines. You might notice this type of aging on your body, where your skin has been protected, or on your face if you have mostly avoided the sun throughout your life.

Photoexposed skin, which is subject to both intrinsic and extrinsic aging, shows slightly different signs of cellular aging. Unlike the thinner epidermis seen in intrinsically aged skin, photoexposed skin shows signs of thickening in the outermost layer of the epidermis, the stratum corneum. Extrinsically aged skin also shows signs of hyperpigmentation, premature wrinkling, and telangiectasia–visible blood vessels on the surface of the skin. For most people, this type of aging shows up as thicker, drier, coarsely wrinkled skin with loss of elasticity and visible dark spots. The most common areas for this type of aging are the face, hands, neck, and chest–areas that have been exposed to the sun chronically over the course of a lifetime.² The good news is that most extrinsic aging is preventable. Up to 80% of facial skin aging is caused by UV rays; wearing sunscreen daily and avoiding extended sun exposure is our most powerful tool in preventing extrinsic aging.³ Other lifestyle shifts can also make a difference: avoiding cigarettes and eating a diet high in fresh vegetables and low in processed foods can also help.⁴ If you live in an urban area, air pollution is another environmental factor to consider. ⁵When it comes down to how to remove dead skin cells from your face and body as a whole, using an air purifier in your home and regularly cleansing your skin at the end of each day ensures that your skin is clear of pollutants that can trigger cellular senescence.

Because intrinsic aging occurs as a result of our genetics, scientists have long thought that there is little we can do to prevent it. But as the field of longevity science continues to grow, researchers have discovered that prevention is possible. Discovered by OneSkin longevity scientists, our OS-01 peptide has been shown to reduce the accumulation of senescent cells* – the central hallmark of intrinsic skin aging. By reducing the accumulation of these cells, the OS-01 peptide – used in our OS-01 FACE and OS-01 BODY topical supplements – helps diminish the burden of both intrinsic and extrinsic aging, extending your body’s ability to keep up with the natural rate of senescence.

This means skin not only looks younger, it also acts like younger skin on a cellular level. Visibly, these benefits can show up as reduced fine lines, smoother skin texture, minimized dark spots, and improved skin firmness – all signs of improved skin health.

* Shown in in vitro fibroblast cultures from patient-derived samples

• Intrinsic aging is caused by internal genetic factors while extrinsic aging is caused by external factors
• Intrinsic aging appears as fine lines and loss of firmness while extrinsic aging appears as coarser wrinkles and dark spots.
• At the heart of both types of aging is cellular senescence, the accumulation of aged cells that trigger skin damage.
• Extrinsic aging can be prevented by wearing sunscreen, eating healthy, and avoiding cigarettes
• The OS-01 peptide has the potential to improve overall skin health by preventing intrinsic aging caused by the accumulation of senescent cells (shown in in vitro skin cultures from patient derived samples).

References:

1. https://platinumdermatology.com.au/articles/extrinsic-vs-intrinsic-ageing-whats-the-difference/
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6047276
3. https://platinumdermatology.com.au/articles/extrinsic-vs-intrinsic-ageing-whats-the-difference/
4. https://biopelle.com/latest-blog-posts/intrinsic-aging-extrinsic-aging-skin/
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6047276