Researchers at a British cancer research organization said a seven-fold increase in the number of older residents who developed malignant melanomas over the past 40 years may be due to the increased ease of travel to places that are sunny and warm.

According to the study, which was conducted by Cancer Research United Kingdom, 5,749 British residents 65 or older were diagnosed with skin cancer each year between 2009 and 2011. Only 608 cases of skin cancer were reported among people in this age group each year between 1975 and 1977.

CRUK’s researchers noted that over the past four decades, there was an explosion in the number of inexpensive trips designed to give people in this age group a chance to visit warmer, tropical climates where they’d be exposed to a lot of sunshine. They said this was likely tied to the increase in skin cancer cases.

They also blamed the increase in skin cancer cases on “the desirability of having a tanned appearance even at the expense of painful sunburn” and warned that even getting just one sunburn every two years can triple a person’s chances of developing skin cancer.