People over the age of 65 are about seven times more likely to develop malignant melanoma than they were 40 years ago, and researchers believe the rise in cases is linked to the "cheap holiday package boom" that started in the 1960s.

Getting sunburned just once every two years can triple one's risk of developing skin cancer, Cancer Research U.K. reported.

"I was part of the generation where package holidays became affordable and you could go abroad nearly every year," Sue Deans, a 69-year-old retired teacher and mother of three, was first diagnosed in with malignant melanoma 2000 and re-diagnosed in 2007. "I don't think there was much understanding at the time about the impact that too much sun can have on your risk of getting skin cancer. And I loved the sun but suffered quite a bit of sunburn over the years.

About 13,300 people are diagnosed with malignant melanoma in the U.K. annually, and about 2,100 people die from the disease. Around 5,700 pensioners are diagnosed with skin cancer today, compared with only 600 in the 1970s.

"It's worrying to see melanoma rates increasing at such a fast pace, and across all age groups. It is very important for people to take care of their skin in the sun. It is also important for them to keep an eye on their skin and seek medical opinion if they see any changes to their moles, or even to normal areas of skin. Melanoma is often detected on men's backs and women's legs but can appear on any part of the body," said professor Richard Marais, Cancer Research U.K.'s skin cancer expert.

The researchers are urging people to take precaution in the Sun this summer by regularly applying strong sunscreen, wearing T-shirts when outside, and spending time in the shade.

 "Many cases of malignant melanoma, the most serious form of skin cancer, are preventable by taking precautions in the sun and making sure you don't burn," said Julie Sharp, Cancer Research UK's head of health information.

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