Introduction
It's a hot summer, the days are long, and many of us are spending more time outdoors.
As dermatologists, this is also the time of year when we see the consequences of increased ultraviolet (UV) exposure, from sunburn and pigmentation to premature skin ageing and, over the longer term, skin cancer.
So, as you enjoy the summer, here are some important reminders about protecting your skin.
You don't need to burn to damage your skin
One of the most common misconceptions about sun exposure is that if you don't burn, you haven't damaged your skin.
Unfortunately, this isn't true.
UV radiation can damage the skin without necessarily causing visible redness or a sunburn. Excessive UV exposure is a major preventable risk factor for skin cancer, including melanoma and non-melanoma skin cancers [1,6].
This means that someone who tans easily and rarely burns can still be accumulating significant UV damage.
Read more about melanoma and how it is detected
A tan is not a sign of healthy skin
A tan may look healthy, but biologically it represents the skin responding to UV radiation.
When the skin is exposed to UV, melanocytes increase melanin production. The resulting pigmentation provides some protection, but it does not make tanning safe.
A tan is a response to UV exposure — not a sign that your skin is becoming healthier.
This applies whether the tan comes from lying on the beach, sitting beside the pool or using a sunbed. The European Code Against Cancer recommends avoiding excessive sun exposure and never using sunbeds [4].
More on why you should never deliberately tan
"I only went a little pink"
It is easy to dismiss mild redness after a day in the sun.
But sunburn is a visible sign of UV-induced skin injury. Repeated sunburns are associated with an increased risk of melanoma.
A large meta-analysis of 51 independent study populations found that melanoma risk increased with increasing numbers of sunburns during childhood, adolescence, adulthood and over a lifetime [5].
So even if you don't blister or peel, sunburn is something we should try to prevent — not something to regard as harmless.
Sunburn fades — the damage doesn't simply disappear
The redness settles. The peeling stops. Eventually the skin looks normal again.
But the biological effects of UV exposure don't necessarily disappear when the visible signs do.
UV damage is cumulative.
Repeated exposure contributes to premature skin ageing and increases the risk of skin cancer [1,4,6].
This is why protecting your skin consistently is important, even if you have never experienced a dramatic sunburn.
What about repeated sunburns?
You may have heard different rules about how many sunburns are "too many" — from "three strikes and you're out" to the often-quoted figure of five sunburns doubling your risk.
The reality is more nuanced.
There isn't a magic number of sunburns at which your melanoma risk suddenly changes. Rather, research shows a dose-response relationship: as the number of sunburns increases, so does the risk of melanoma. This association has been observed for sunburns occurring during childhood, adolescence, adulthood and across a lifetime [5].
There are, however, some specific figures worth knowing. The American Academy of Dermatology reports that experiencing five or more blistering sunburns between the ages of 15 and 20 is associated with an 80% increase in melanoma risk [6].
So rather than counting sunburns and waiting for a particular number, the practical message is much simpler:
Every sunburn is one to avoid. The fewer sunburns you experience over your lifetime, the better.
And this is particularly important for children and teenagers, when preventing excessive UV exposure can help reduce skin-cancer risk later in life [1,5,6].
Your skin doesn't only need protection at the beach
UV exposure happens during everyday life too.
Walking, exercising, gardening, playing sport, eating lunch outdoors or sitting beside a swimming pool can all contribute to your cumulative UV exposure.
And remember: UV radiation cannot be seen or felt.
A cool or cloudy day does not necessarily mean that UV levels are low. The UV Index is a much better guide to UV intensity than temperature.
The World Health Organization recommends sun-protection measures when the UV Index reaches 3 or above [1,3].
Why sun protection matters every day
So, what should you actually do?
Summer should absolutely be enjoyed. Good sun protection doesn't mean staying indoors — it means reducing unnecessary and excessive UV exposure.
1. Check the UV Index
Don't judge UV exposure by how hot it feels.
The higher the UV Index, the greater the potential for skin and eye damage. The UV Index provides a useful guide to when additional sun protection is needed [1,3].
2. Seek shade
Try to reduce prolonged direct exposure, particularly when the sun is strongest.
Shade is especially useful during the middle part of the day and during the summer months [2,4,6].
Remember, however, that shade does not eliminate UV exposure completely, particularly around reflective surfaces such as water, sand and snow [4,6].
3. Cover up
Clothing, a wide-brimmed hat and UV-protective sunglasses provide excellent physical protection.
For prolonged outdoor activities, clothing can be one of the most effective ways of reducing UV exposure. Where possible, consider clothing labelled with an ultraviolet protection factor (UPF) [2,6].
4. Use sunscreen — but don't use it to extend your time in the sun
Choose a sunscreen that provides:
- Broad-spectrum UVA and UVB protection
- SPF 30 or higher
- Water resistance, particularly if swimming or exercising outdoors
These are the three key features recommended by the American Academy of Dermatology [7].
Apply sunscreen generously to exposed skin and reapply as directed, particularly after swimming, sweating or towel drying. The AAD recommends reapplying approximately every two hours when outdoors, and after swimming or sweating [6,7].
And remember: sunscreen should complement shade and protective clothing — not be used as a way of extending the amount of time you spend in direct sunlight [1,2].
Everything you need to know about choosing and applying sunscreen
5. Don't forget the easily missed areas
Ears, the hairline, scalp, neck, décolletage, backs of the hands and tops of the feet are frequently overlooked.
These areas can receive considerable cumulative UV exposure and should be included whenever you apply sunscreen [6].
See what missed areas actually look like
And finally…
Summer is meant to be enjoyed.
We don't need to fear the sun — but we do need to respect UV radiation.
You don't need a blistering sunburn to have experienced excessive UV exposure. You don't need to turn red for UV damage to occur. And a tan is not a sign of healthy skin.
Protect your skin now, because the skin you're protecting today is the skin you'll have for the rest of your life.
