Why Residents in Southern China Live Longer Than Those in Northern China?

Abstract Background: Life span of human beings is closely related to the natural geographical environment and regional lifestyle. Since 1982, the life expectancy and longevity level in southern China is always higher than northern China, and the standardized mortality rate in northern China is always higher than southern China. Method: By calculating the contribution of four diseases to longevity in 31 provinces of China, this study found that cardiovascular disease is the main reason for the longevity disparity between northern China and southern China. The population attribution fraction of nine major risk factors of cardiovascular disease in each province were calculated based on their exposure value and relative risk. Results: residents live in northern China eat more sodium, less vegetable and less sea products, they are more likely to be overweight. PM2.5 in northern China is much higher than in southern China. Cold temperature causes more number of death than hot temperature because of the longer cumulative risk, all these factors lead to higher CVD mortality rate, shorter life expectancy and lower life span in northern China. Diet high in sodium is the leading cause of north-south life span differential. Conclusions: Changing diet habits, controlling air pollution can effectively reduce the loss of health and life span in northern China.