We aimed to conduct a narrative review of the rapid advances in knowledge regarding sun exposure and all-cause mortality. Data support the hypothesis that sun exposure avoidance is a major risk factor for all-cause mortality in adjusted analysis (age, income, education, marital status, smoking, and comorbidity). This was caused by an increased risk of death due to cardiovascular disease (CVD) and noncancer/non-CVD. However, the increased life span among those with high sun exposure naturally results in an increased prevalence of cancer death. In addition, sun exposure increases the incidence, but is related to better prognosis of skin cancer. The new findings indicate that there is a need for modification of guidelines regarding sun exposure. They may also add to our knowledge regarding the increasing incidence of diabetes mellitus and increased mortality among non-Caucasians in western countries. According to the present knowledge, in a low solar intensity region we should aim for sound and safe sun exposure habits, especially for those at increased risk of CVD or noncancer/non-CVD.