Rates of the deadliest form of skin cancer are continuing to rise in Cornwall, according to new research.
There are more deaths from skin cancer in Britain than Australia
Research by the Royal Cornwall Hospital in Truro and Plymouth's Derriford Hospital show cases of malignant melanoma rose by 18%.
The statistics cover a two-year period between 2003 and 2005.
Cornwall has the highest skin cancer rates in the country, but doctors had hoped warnings and safety advice would have led to a decline in case numbers.
Doctors believe people have not adjusted culturally to Britain's hotter summers - they have changed their lifestyles to take advantage of good weather but are still not taking the necessary precautions.
Britain now has more deaths from skin cancer than Australia, where people are more used to covering up in the sun.
Researchers fear an increase is likely to be mirrored elsewhere in the country.
Figures released by Cancer Research in April show cases have increased by 29% in men and 14% in women over the past 10 years.
Skin specialists say too many people mistakenly believe they can stay in the sun for longer if they use high-factor sun screens, but significant skin damage can be caused, even if sun screens prevent burning.
Experts' advice include staying out of the sun between 1100 and 1500 BST, covering up with a T-shirt, wide-brimmed hat and sunglasses, using a high-factor sun screen and drinking plenty of non-alcoholic fluids.