Why Does Our Skin Become Drier As We Age?

There is the answer we’ve read before to this question and then there is a much more interesting one.

As we age our skin produces less of some of the substances it once made quite readily. We’ve all heard this so many times. Once you start living it though suddenly this question becomes something quite important. Hormones change, cell turnover slows, the skin becomes thinner and cumulative damage from the sun and our environment begins to show itself. All of this is true.

But there is another change that I think is particularly important when thinking about how we should care for skin thats seen a lot of life.

The skin becomes less able to maintain itself.

Think about what we ask of our skin over a lifetime. We wash it, expose it to hot water, change its colour, subject it to razors and scrubs, cold air, wind and sun. We dissolve some of its oils with cleansers, rub some of its protective surface away, sweat through it and occasionally injure it. Most of the time we don’t think about any of this because skin quietly repairs the damage and gets on with its job.

It has to.

Inside your body it’s a very wet place. This watery environment allows the many thousands of chemical reactions and transfers required to keep you alive to occur. Your skin has the rather extraordinary job of keeping that wet environment closed up and sealed off from the outside, while still remaining flexible enough to move, strong enough not to tear easily and permeable enough to interact with the world around us.

And it has to keep doing this, we hope, for close to a hundred years. It’s a rather extraordinary feat and no flexible material man has made has been able to last a hundred years.

So skin can’t simply be a waterproof sheet wrapped around us. The only way to achieve such longevity has been to continuously grow, shed, repair and rebuild itself.

When we are young it is particularly good at this.

If we disturb the protective barrier, the skin responds by making more of what it needs to repair it. The outermost cells of our skin are surrounded by a carefully organised mixture of fats, including ceramides, cholesterol and fatty acids. Inside those cells are substances including urea, lactates and amino acids that help them hold onto water.

Together these compounds help create a covering that is remarkably good at keeping our very wet insides wet, clean and protected.

As we age, however, our skin becomes less efficient at maintaining itself.

We produce less of some of the fats needed to build the barrier. We produce less of the water-holding lactate and Urea systems. Cell renewal slows. Sweat and sebum production change and, importantly, when the barrier is disturbed it takes longer to repair itself. The skin feels dryer, harder, rougher, thinner.

Researchers have demonstrated this change by deliberately disrupting the skin barrier of younger and older people. The interesting difference wasn’t simply the condition of their skin beforehand. It was what happened afterwards. The older skin took considerably longer to repair the damage, particularly if it was in poor condition.

You may already have witnessed this without knowing the biology behind it.

Perhaps you have always loved a very hot shower. When you were 25 your skin was quite capable of dealing with it. The hot water removed some of the fats and water-soluble compounds from its surface and your skin got busy replacing them.

Do exactly the same thing decades later and the shower hasn’t changed.

Your skin’s capacity to recover from it has.

The same is true of the cleanser you’ve used for years, the cold dry winter air you’ve always lived through or the scrub you’ve always liked. Something your skin once compensated for easily can gradually become something it struggles to keep up with.

For women, there is another significant change occurring around this time. Skin is responsive to oestrogen and as oestrogen declines through menopause there are changes in hydration, collagen, skin thickness, healing and the fats that form part of our skin barrier. These changes occur right when we feel the first significant ageing signals. Skin becomes significantly drier at this change.

Then we add the accumulated effects of decades of sunlight and environment, you know, those hugely fun years you would never change and are still doing today.

None of this means our skin has stopped working. It is still growing, producing oils and fats, holding water and repairing itself.

It simply doesn’t have the same capacity to do all of these things that it once did.

And this is where I think the idea of ageing skin becomes much more interesting.

If our skin is making less of some of the substances it needs, holding water less effectively and taking longer to replace what we remove, what happens if we stop some of things we used to do and start giving it some of the things it really needs instead?

Quite a lot of the functional consequences of ageing could potentially be compensated for, even though the underlying ageing process would continue.

Urea and lactates are substances our skin already uses to help hold water. Ceramides, cholesterol and fatty acids are among the materials it uses to construct its barrier. Oils, fats and waxes can soften and protect the surface and help slow the movement of water from our skin into the atmosphere. Vitamins help skin cells produce what they need and heal in a timely manner.

This isn’t making old skin young again.

It is recognising what an ageing skin is finding increasingly difficult to do for itself and supporting it in ways that it needs.

This is how I think people should view ageing skin, its always been how I’ve viewed it. Coming from a scientific background ageing has always being natural and inevitable but there is good paths that have good outcomes.

There is an enormous amount of language around skincare concerned with anti-ageing.

I find the biology more useful than the phrase.

We cannot stop an organism from ageing and I don’t think ageing itself is something that needs to be treated as a failure.

What we can ask is:

What is this skin finding more difficult to do for itself now? How do I get that healthy glow back?

If it is manufacturing fewer barrier lipids, we can consider how we support those lipids.

If it is struggling to retain sufficient water, we can supply compounds such as urea, lactate and glycerol that help create a hydrated stratum corneum.

If its surface is becoming more vulnerable to water loss, oils, fats and waxes can provide emollience and protection.

If its requirement for particular vitamins remains high while its biological circumstances to provide them have changed, we can consider whether those compounds should be supplied more often or in higher amounts.

And perhaps equally importantly, if an older skin takes longer to repair itself, we can stop unnecessarily damaging the barrier in the first place.

Hot water, repeated detergent cleansing, excessive exfoliation and other repeated disturbances become more consequential when the system repairing them is no longer working at the speed it did at twenty.

There is a subtle but important difference here.

The aim isn’t to force older skin to behave like young skin.

It is to give older skin more of the conditions and materials it needs to function well as older skin.

The underlying ageing process continues.

Collagen will still change. Hormones will still change. Cell populations and signalling will change. Decades of sun exposure cannot simply be erased and the skin’s capacity for repair will not remain what it was in early adulthood.

But this doesn’t mean we should do nothing or have to accept dry skin thats dry, dull and lifeless.

If a system has become less efficient at supplying itself with some of the materials it requires, those are exactly the circumstances in which thoughtful supplementation makes sense.

Over a day the difference may simply be skin that feels softer and more comfortable.

Over years and decades I think the more interesting question is how differently skin behaves when it has spent considerably more of its life hydrated, flexible, protected and adequately supplied, rather than repeatedly becoming depleted and then being asked to repair itself.

That, to me, is a much more sensible way of thinking about ageing skin.

Not preventing ageing.

Supporting the biology that is still very much alive underneath it.

Lets go the distance in good shape shall we.