The World Health Organization (WHO) published the "World Health Statistics 2015" that represent the official source and annually updated information on the world population health.
The data contained in the WHO annual publication come from 194 countries and offer a range of indicators, including life expectancy, deaths from diseases, health services and treatments, investment in health, as well as behavior and risk factors for health.
For further information, you can consult the dedicated section on the WHO website.