How the Sun Ages Your Skin

I’ve always gone on about how integral sun protection is as part of your anti-ageing arsenal.

It’s one thing to just know that the sun damages and ages your skin cellularly, but it’s another to see the effects visually. A faded tattoo is a fantastic example of the cumulative power of UV exposure.

I recently came across a fascinating twin study all about ageing. It explores which genetic and environmental factors have the biggest impact on people’s perceived age. I wanted to know which features of your skin make you look older or younger, and whether or not they are things we can control. What I learnt proved my suspicions right...

Let’s start off by looking at the two specific skin issues that are created by sun damage that made the women appear older: wrinkles and pigmentation.

Wrinkles are a side effect of sun damage

This study (and many others) states that “skin wrinkling is one of the main features indicative of the severity of sun-damage present in faces, predominantly when it appears alongside other features typical of sun-damage in exposed body sites”. In other words, you can tell how much sun someone has had simply by looking at the severity of their wrinkles.

Wrinkles make you look older

Upon looking at the lifestyle data they collected from the participants and ratings from those who viewed their portraits, they concluded that “facial skin wrinkling and wrinkle depth in the crows feet area were significantly and strongly correlated to sun-damage” and that “sun-damage was significantly and strongly correlated to the perceived age”.

They do, however, mention that “repeated skin contouring caused by forces external to the skin and by muscle contractions have also been implicated in the development of skin wrinkles.” So we can’t *just* blame the sun.

Pigmentation is caused by the sun

This study concludes that “the pigmented spot grading had a significant but weak to moderate correlation with wrinkles and sun-damage after adjusting for chronological age”.

Let’s break that down: many people in the study who had sun-damage and wrinkles also suffered from pigmentation. They explain this by saying that “although sun-exposure causes an increase in the number of pigmented spots, it does so differentially depending on the skin type of the individual”. This goes to show how different ethnicities and skin types show their sun damage differently. It seems that wrinkling is a more universal indicator of sun damage as opposed to pigmentation issues. In terms of the potential range of pigmentation people have, they mention age spots which are most prevalent in Asian skin as opposed to freckling and melasma which is prevalent in Caucasian skin.

Pigmentation is correlated with older-looking skin

The study found that “there was a significant correlation between the perceived ages of the British subjects and the pigmented spot grading”. This means that the higher the intensity and amount pigmentation on their skin, the older the participant appeared to viewers.

However, after adjusting for real age (aka. comparing people of the same age only), this correlation is no longer statistically significant. This affects our conclusions.

One way to interpret that data is that all people gain more pigmentation as they get older. This study suggests that pigmentation does come along naturally as you age, but it is not necessarily the reason you seem older than somebody the same age as you without pigmentation. Although more pigmentation is related to an older perceived age in general, it does not have a huge effect on how old you look for your age according to this specific study. Those doing the study mention that this is something they would be interested in doing further study into, and I can’t wait to read it.

In summary: sun damage leads to wrinkling in all skin types, and pigmentation in some. Both wrinkles and pigmentation are positively correlated with older skin, and wrinkles are correlated with older looking skin even compared to those of the same age.

What do these have in common?

In interesting but unsurprising findings, both of these major factors in perceived age are caused by sun damage! Not only that, but so much of how we age is in our control.

In comparing fraternal and identical twins, researchers got an idea of what ageing processes which genetic and which were environmental. They found that 40–59% of skin ageing might be attributable to environment and care! To a certain extent, your natural skin tone and propensity for DNA self-repair enzymes are an unchangeable factor, but those who spend more time in the sun undoubtedly accumulate more DNA damage than those who don’t. This leads them to suffer from all of the above conditions. And as they found, these have an effect on how old you are perceived to be by others.

We are in control of so much of our appearance, and all we have to do is religiously use high SPF sunscreen and other protective measures like antioxidants. If this study doesn’t convince you, I don’t know what will!

If you’re curious to learn more about the research methodology or other factors that played into perceived age such as lip fullness and hair recession, read the full study here.