UV, Sun Damage and Photoageing: Protecting Your Skin

If you want to know what your skin will look like in twenty years, the honest answer has more to do with how you treat the sun than how many candles are on your birthday cake. UV exposure is estimated to be responsible for around 80% of the visible signs of facial ageing — the wrinkles, the uneven tone, the loss of firmness we tend to blame on getting older. The encouraging flip side is that most of it is preventable. Here is a clear, evidence-based look at how the sun ages your face, and what genuinely helps.

Why the sun ages your skin

Ageing comes from two directions. Intrinsic ageing is the slow, genetically programmed change that happens to everyone over time. Extrinsic ageing is driven by outside factors — and UV radiation is by far the biggest. We call the resulting sun-driven damage photoageing, and it is the reason skin on habitually exposed areas like the face, neck and backs of the hands looks so different from skin that stays covered. If you want to see intrinsic ageing in isolation, look at skin that rarely sees daylight.

The distinction matters because it reframes sun protection as an anti-ageing tool, not just a cancer-prevention chore. We explore the two mechanisms in more detail in our guide to intrinsic versus extrinsic ageing.

UVA vs UVB: two very different threats

Not all ultraviolet light behaves the same way. The two types that reach us do quite different things to the skin.

The takeaway is that UVA, the deeper-penetrating ageing ray, is with us on grey days, in winter, and even beside a sunny window. This is precisely why dermatologists recommend daily protection rather than reserving sunscreen for the beach.

What is actually happening under the surface

Photoageing is not vague “damage” — it is a set of well-understood biological processes:

• Collagen breakdown. UV switches on enzymes called matrix metalloproteinases (MMPs), which literally digest collagen. At the same time it suppresses the body’s natural brake on those enzymes, so the scaffolding that keeps skin firm degrades faster than it is replaced.
• Elastin damage. Chronic exposure causes abnormal, disorganised elastic fibres to build up — the hallmark of solar elastosis, which leaves skin looking thickened, leathery and yellowish.
• DNA damage. UVB directly harms the DNA of skin cells, contributing both to visible ageing and to skin-cancer risk.
• Pigment changes. UV overstimulates the cells that make melanin, producing sun spots (lentigines), blotchiness and uneven tone.

Together these show up as deep wrinkles, crepey texture, broken capillaries, age spots and dullness — the classic photoaged face.

Around 80% of the visible signs we associate with facial ageing are attributed to the sun. In other words, most of “looking older” is really accumulated, preventable sun damage.

The UK reality: a stubborn tan culture

Britain is hardly famous for its sunshine, yet a cultural attachment to looking tanned persists — and the statistics are sobering. Melanoma cases in the UK have hit a record high, and Cancer Research UK reports that nearly 9 out of 10 melanoma cases are caused by too much UV from the sun and sunbeds, making it one of the most preventable major cancers.

Sunbeds remain a particular problem. A 2024 survey found 28% of UK adults aged 18–65 currently use them, rising to 38% of 18–35-year-olds. That matters because the International Agency for Research on Cancer found that first sunbed use before age 35 increases melanoma risk by 75%, and modelling links sunbed use to roughly 100 melanoma deaths a year in the UK. There is no safe tan from a sunbed — the tan itself is a visible sign of DNA damage.

Decoding sunscreen: SPF and the UVA star rating

Sunscreen is the most cost-effective anti-ageing product you will ever buy, but the labelling confuses almost everyone.

SPF measures UVB protection only. SPF 30 blocks around 97% of UVB; SPF 50 around 98%. The percentage gap looks small, but it can matter over a lifetime of daily exposure and for higher-risk skin.

For UVA — the ageing ray — the UK uses the Boots star rating, from 0 to 5 stars, showing how balanced a product’s UVA protection is against its SPF. Separately, a UVA logo in a circle on UK and EU products confirms UVA protection is at least a third of the labelled SPF.

The practical rule from Cancer Research UK and dermatologists is straightforward: SPF 30 or higher with a 4–5 star UVA rating, applied generously — roughly a teaspoon for the face and neck — and reapplied every couple of hours when you are outdoors. Most people apply far too little, which quietly halves the protection on the label.

When does the damage happen?

You may have heard that “80% of sun exposure happens by age 18.” It is a memorable line, but the evidence is shakier than it sounds — more careful studies suggest somewhere between 25% and 50% of lifetime UV exposure occurs before age 18–20, with the rest accumulating steadily through adult life. The honest message is more useful anyway: early protection matters, but it is never too late to start, because you are still adding to the total every year. Protecting your skin at 45 still spares it decades of future damage.

Beyond sunscreen, the simple physical measures do a lot of the work: seek shade during the peak midday hours, cover your shoulders, and wear a hat and sunglasses. None of it is glamorous, but it is remarkably effective.

Can you improve existing sun damage?

Prevention is always easier than repair, but photodamage is not a life sentence. Consistent daily SPF from today stops the problem getting worse — often the single biggest change you can make. Beyond that, several evidence-based routes can improve what is already there:

• Topical retinoids are the gold-standard at-home ingredient for photoageing, stimulating collagen and improving tone and fine lines with consistent long-term use.
• Chemical peels resurface the skin to soften pigmentation, dullness and fine lines, with different depths for different severities.
• Collagen-building tightening. Where sun damage has left skin looking crepey and lax rather than simply pigmented, treatments that rebuild the deeper support layers can help. Non-surgical options such as HIFU and radiofrequency skin tightening work by stimulating your own collagen gradually over several months — a natural, progressive firming rather than an overnight fix.

Because sun damage rarely shows up as just one thing, the right plan usually combines protection, the right topicals, and a targeted in-clinic treatment or two. And what you put into your body matters as well as what you put on it — our guide to diet and facial ageing looks at how nutrition supports healthier skin.

The bottom line

The sun is the biggest single driver of how your face ages — and, uniquely among ageing factors, it is one you can largely control. Daily broad-spectrum SPF, sensible shade and a firm no to sunbeds will do more for your long-term appearance than almost any product or procedure. And if photodamage has already left its mark, that is not the end of the story.

If you would like an honest assessment of your skin and a realistic plan to protect and improve it, book a consultation with our team. We will look at your skin properly, talk through what will genuinely help — from everyday habits to collagen-building treatments like HIFU — and help you feel confident in your skin for years to come.