Everyone knows that sunburn increases your risk of skin cancer. However, properly protecting yourself from it is not as simple as slapping on sunscreen. Sunburn is caused by exposure to two types of radiation emitted by the sun: UVA and UVB. However, many people don’t realise that the sun protection factor (or SPF) of suntan cream measures only how effectively it protects you from UVB rays, not UVA, which are a prime cause of skin-wrinkling.

Professor Richard Marais, a melanoma specialist and spokesman for the Institute of Cancer Research, says that when choosing sunscreen it’s essential to look for broad-spectrum protection – protection against both types of ultraviolet radiation. UVA protection is denoted by a star rating between one (the lowest) and five.

Sunscreens of the same SPF don’t all offer the same protection and effectiveness is not related to cost. It’s also a matter of finding a consistency of cream that you like. “People should be prepared to try two or three creams to see which is better,” says Marais. “Use one which is at least SPF15 or more.”

The higher the SPF the longer a sunscreen protects you (SPF5 lets you stay safely in the sun five times longer than does SPF1). Reapply at least every two hours, and apply a lot – the World Health Organisation recommends one tube of sunscreen per three whole-body applications. Note that sunscreen takes half an hour to work, so putting it on when you’re already outside is pointless.

You are more likely to burn if you are in or near water, because the sun is reflected by the surface. And you will burn more rapidly at altitude, where UV rays are stronger. Wearing clothes will not necessarily protect you: according to Cancer Research UK, thin, loose-weave fabrics such as cheesecloth provide very little protection.

Don’t neglect your eyes. Long-term exposure to UV rays can cause loss of vision and cataracts. Wear shades and ensure they carry the European Standard CE mark or the British Standard BSEN 1836:1997, which means they block at least 99% of UV rays.

Sunburn begins three to six hours after exposure and usually peaks by 24 hours. If you are caught out, apply aftersun lotion containing aloe vera. Don’t put soap on the area because this will dry it out, and avoid greasy creams that can block the sweat glands and stop heat from escaping.

The effects of the sun

Your skin

UV rays damage the skin’s DNA. When the damage is severe, a normal skin cell may begin to grow in an uncontrolled way, resulting in cancer. Melanoma, the severest type of skin cancer, affects the pigment-producing cells (melanocytes)

Identify your skin type

The speed at which you burn depends on your skin type, and there are six types. Fair skinned, freckly people (Type 1) are most at risk. People with naturally black-brown skin and black-brown eyes (Type 6) are the least

Beware of rays

You can burn when you least expect it. That includes when it’s overcast or if you are underwater. About 80% of UV rays go straight through clouds and are reflected off snow, water and sand (so you can burn under a parasol)

TAKING IT FURTHER

www.eye-care.org.uk

The best advice for choosing sunglasses

www.massgeneral.org/cancer/crr/types/skin/ info.asp

Clear if slightly gruesome pictures of characteristics of melanoma and what changes to look out for

www.plwc.org

Patient information site; has a section on questions to ask a doctor if you are worried about skin cancer

Kit bag: Essential gear for the sun

Sundowner Roo hat £50 www.hoof-and-horn.com

Beware, baseball caps do not provide enough protection from the sun. In order to protect your head fully from the sun’s rays you need a wide-brimmed hat. This Australian bush hat, made from kangaroo hide, covers that nicely. It’s fully foldable and the maker claims it offers UV protection of factor 50+.

Solar Safe Sun Monitor £5 for seven www.solarsafe.com

This disposable UV-monitor wristband tells you when you need to reapply your sunscreen. Slip it on, coat it with sunscreen when you apply it to yourself, and when the time is right for you to apply another layer, the monitor changes colour, informing you to do so.

Sunsense Sport Gel SPF 30 £10 01477 537 596

You may need to try several sunscreens before you find the one that best suits you. The Australians have more reason than most of us to worry about harm from the sun, and this high-factor gel is what the Australian Institute of Sport thoroughly recommends for its own athletes.

Ray-Ban Aviator sunglasses £70 www.ray-ban.com/uk/home.asp

Aviator sunglasses were first developed by Ray-Ban in 1937 to match the style sold to the military, and now they’re back with a vengeance. This pair conforms to the British Standard, so will protect your eyes from at least 99% of UV rays, and they’re snazzy to boot.

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