Should I worry about how much sun I get?

‘I can’t help myself, I’m in love with the summertime,” Divine Comedy frontman Neil Hannon once crooned – and though it’s a sentiment shared by every red-blooded bank holidayer, it’s probably fair to say that sunny afternoons come with a tinge of concern these days. We’re all aware that we probably should be re-applying the factor 50 more often than we do, especially after swimming, but does the state of the ozone layer make things worse? Is the sun somehow … hotter now?

“The most fundamental thing to understand is that sun exposure without use of high-factor sunscreen or protective clothing is a health hazard,” says Dr Derrick Phillips, consultant dermatologist and spokesperson for the British Skin Foundation. “Cumulative sun exposure over a lifetime damages skin proteins and cellular DNA, causing mutations and increasing the risk of developing skin cancers. Also, the skin becomes less effective at repairing damaged DNA over time. There is currently no way of reversing cumulative DNA damage, and so past sun exposure determines your present risk of skin cancer.”

We’re exposed to two forms of ultraviolet radiation from the sun: UVA and UVB. UVA can penetrate clouds and window glass, so it’s still a concern if you’re in the office, or there’s a brief break in the direct glare on a scorching day. UVB peaks during the summer months, and is especially dangerous when the sun is high in the sky around midday, or in areas where the ozone layer is thin, like Australia. It can directly damage the DNA of skin cells, causing mutations and leading to cell death and inflammation.

UVA is present all year round, penetrates deeper into the skin and damages the collagen and elastin that keep it looking springy and youthful. “UVA is responsible for 80% of the signs of skin ageing – fine lines, wrinkles and pigmentation,” says Phillips. Both are carcinogenic, but UVB is worse. Short exposure can cause mutations that lead to the development of melanoma, while long-term cumulative exposure is associated with non-melanoma skin cancers that tend to occur later on in life.

Oh, and it’s not just the carcinogenic effects you need to worry about. Scientists are starting to understand that excess UV exposure can lead to a raft of other negative effects, including a weakened immune system.

So far, so depressing – and it’s also worth noting that fair skin, red hair and freckles do increase your susceptibility to the sun’s radiation, as does a family history of skin cancer. So what’s the solution? “Sunscreen protects the skin from the harmful effects of UV radiation,” says Phillips. “It should really be applied to exposed sites all year round, but particularly during the summer months and on sunny holidays. Studies have shown that most people do not apply enough sunscreen to get the level of protection on the label. To keep your family safe, we recommend using a sunscreen with at least SPF30 and 5-star UVA protection. It should be applied every two hours and more frequently if you are swimming, or performing any activities that will cause you to sweat.” In other words, follow the instructions on the bottle, and do it before you go out, as it can take 15 minutes to be absorbed into the skin.

If you’re relying on your clothes to protect you, consider what you’re wearing: tight weaves offer excellent protection, while loose weaves are more easily penetrated. An average cotton shirt actually provides poor protection — with an ultraviolet protection factor (UPF) rating of about 5 — as compared with sun protective clothing that can be rated from UPF 30 to 50+. Long-sleeved, loose-fitting clothes with a high neck are a good idea, as is a broad-brimmed UPF rated hat and sunglasses.The Skin Cancer Foundation advises that more intensely coloured clothes offer better protection as they prevent more rays from getting to you. If you’re caught without your factor 50 in the beer garden, consider having a fruity mocktail: one small-scale study suggests that alcohol actually increases the risk of sunburn while vitamins C and E together seem to offer a slight protective effect.

Finally, there really is one good reason to stuff an old airport paperback in your suitcase, rather than bringing a tablet to read on holiday: the latter can actually reflect the sun’s UV rays back into you, giving you a higher dose than normal. Oh, and you probably shouldn’t be using a sunbed under any circumstances. But the Divine Comedy never wrote a song about those anyway.