Skin. We are born in it and expect to keep it for life, which in the UK now averages more than 80 years. Our ‘birthday suit’ is a window through which the outside world quickly judges our health and vitality according to what it sees. If our skin looks good, we feel good; if our skin looks bad, it can seem worse than a “bad hair day”.
Skin is vitally important and is also the largest organ of the body, yet we tend to take our skin for granted. Have you ever thought how much our skin has to endure? It must cover us to keep the inside in and the outside out; it must be flexible and move with us; it must grow as we grow over the years; it must repair itself when damaged; and it must constantly renew itself from within to cope with the trials of everyday life as the outermost layer is simply worn away.
Skin is a barrier not a sieve. It is a common misconception that 60 per cent of what you apply to your skin is absorbed, but this couldn’t be more wrong. For example, taking a bath will never quench your thirst. Water molecules are extremely small so if skin keeps water out; it can certainly exclude larger substances.
Actually, it is extremely difficult for any substance to penetrate the skin, which is why so few medicines are administered as patches to achieve systemic effects; most have to be swallowed or injected. The barrier properties of the skin are also vital to ensure we do not ‘leak’ vital substances from our bodies. Furthermore, the skin is not a route for the removal of toxins from the body; we have other efficient systems for that such as our liver and kidneys.
The outermost layer of our skin is paper thin yet incredibly tough. It represents the most important barrier of the body. Our bodies are about 70 per cent water, but without the barrier of the stratum corneum keeping that water in, we would die of dehydration in hours. It also keeps out the many micro-organisms which would love to invade, causing disease.
Underneath that layer is a fantastically complex matrix of cells, the epidermis, which generate and maintain the barrier between us and the harsh external environment. That barrier must withstand anything from searing heat to sub-zero temperatures. Even in the UK it must cope with very low humidity and cold in winter, and high humidity on a hot and thundery summer day.
Beneath the epidermis is the dermis itself; another intricate matrix that includes a scaffolding of collagen and elastin fibres to hold the skin in place, allowing it to stretch and recover, and yet remain in position over the underlying tissues. Our skin does not slip down when we stand up; it moves with us. The dermis includes cells of fat which cushion impacts and insulate us from heat and cold.
There are nerves for all the many sensations of touch and which provide the central nervous system with vital information about our surroundings. And there are blood vessels bringing nutrients to the skin as well as supplying the immune cells that would deal with any micro-organisms trying to invade through cuts and abrasions.
We do not need to reach our senior years encased in careworn leather
However, our skin is not immune to the passing of time. The years take their toll, and our skin reflects the trauma it has been through and the care it has received. Our ability to regenerate and repair reduces as we get older, and it shows. Skin tends to get thinner, to look dryer and more wrinkled and it can change colour, looking uneven, developing blotches and darker ‘age spots’. Damage takes longer to heal. The cumulative effects of ultraviolet (UV) rays, temperature extremes, ranges of humidity or dryness, cuts and bruises, diet and disease will all show. We are pretty good at judging a person’s age and health from the appearance of their skin.
Thankfully, there are whole teams of scientists working within the cosmetics industry whose research and innovations are able to minimise these effects, slowing the rate of skin ageing and enabling each of us to be in the best skin we can. We do not need to reach our senior years encased in careworn leather: we can now protect and nurture our skin in a way that was not possible before.
Skincare is so much more than covering and disguising. Starting with simple moisturising and basic protection from UV rays, we now have the knowledge to understand the skin and its function, as well as developing cosmetic products that ensure our skin will look and feel as good as possible as time passes. We may not reach our mature years with the skin we were born in, but nor does our skin have to betray our age. Amazing science, applied daily – how fantastic is that?