Sun damage is cumulative, beginning with your very first sunburn. The more you burn, the greater your risk of skin cancer, and as little as one blistering sunburn in childhood or adolescence more than doubles your chances of developing melanoma in later life. Getting five or more sunburns more than doubles your risk of melanoma throughout your lifetime. UV damage can also occur even when there's no obvious burn, such as in cloudy weather, which is why sun safety is always important.