What causes skin cancer?
Australia has the highest rate of skin cancer in the world. One in two people who spend their life in Australia will develop some form of skin cancer.
Unprotected exposure to ultraviolet (UV) radiation -- from the sun or other sources, such as tanning machines in solariums -- remains the most important risk factor for skin cancer.
UV radiation cannot be seen or felt but can cause:
- sunburn
- early ageing of the skin
- damage to the skin that builds up over time and can lead to skin cancer.
Skin cancer is usually related to lifetime exposure to UV radiation. Most parts of Australia have high levels of UV radiation year round.
While skin cancer usually appears in older adults, the damage begins at an early age from exposure to UV radiation, especially sunburn.
New research suggests that while cells are often damaged in childhood, it may be sun exposure in adulthood that triggers cells to turn cancerous.
Who is at risk?
Anyone can develop skin cancer. The risk is increased if a person:
- has numerous moles (naevi) on their body
- doesn't protect their skin from the sun, or spends a lot of time in the sun (e.g. working outdoors)
- has a personal or family history of melanoma
- is infrequently, but intensely exposed to the sun (e.g, on holiday or during recreational activity), especially if it results in sunburn
- has fair skin that burns easily, freckles or doesn't tan
- has red or fair hair and blue or green eyes
- has solar keratoses (sunspots) or dysplatic naevi
- a compromised immune system, possibly due to taking certain drugs after an organ transplant or being HIV positive.
People with dark or olive skin have more protection against skin cancer because they produce more melanin than fair-skinned people. However, because UV radiation is so strong in Australia, dark and olive-skinned people still need to protect their skin.
How can I prevent skin cancer?
The best way to prevent skin cancer is to protect your skin from the sun.
You can do this by:
- Knowing the UV index, which shows the intensity of the sun's rays. When the UV index is 3 (moderate) or above, the sun levels are high enough to cause skin damage and sun protection is required. You can check the daily SunSmart UV Alert in most daily newspaper weather forecasts or online.
- Staying out of the sun between 11am and 3pm during daylight saving hours (10am and 2pm at other times of the year) when the sun is strongest. During these hours, more than 60% of the sun’s UV radiation reaches the earth’s surface.
- Using shade from trees, umbrellas, buildings or any type of canopy. Remember to choose your shade carefully. UV radiation is reflective and bounces off surfaces like concrete, water and sand, causing you to burn even when you think you’re protected.
- Wearing clothing that covers as much of the skin as possible, including the back of the neck. A shirt with long sleeves and a collar, trousers, skirts or long shorts that cover the legs or a large part of them are recommended. The best protection comes from closely woven fabric.
- Wearing a hat that shades the face, neck and ears. Hats should have at least an 8-10cm brim.
- Using sunscreen with sun protection factor (SPF) of 30+, and which is also broad spectrum and water resistant, no matter what type of skin you have. Apply sunscreen 20 minutes before going out into the sun and reapply every two hours or after swimming or any activity that causes you to sweat or rub it off.
- Protect your eyes with sunglasses that meet the Australian Standard AS 1067 (check the tag). Wrap-around styles are best.
- Taking care to protect infants and young babies from direct exposure to sunlight. Use shade, umbrellas, clothing and hats to protect them. If necessary, use SPF30+ sunscreen on the areas of skin that cannot be protected naturally, such as the face and the back of the hands.
- Not using tanning bed and sun lamps, which give off UV radiation that can increase the risk of skin cancer.
Some sunlight is important to your health. Vitamin D, which is needed to develop and maintain strong and healthy bones, is made when skin is exposed to UV radiation. However, you only need to be in the sun for about 10 minutes on most days of the week, outside peak UV times, to produce enough vitamin D for good health. Most Australians get enough UV radiation from the sun just by going about their daily activities. |
