Global health data, explained in plain language

The WHO Global Health Observatory holds more than 1,000 indicators for 194 Member States — from life expectancy to immunisation coverage.

What an indicator is

An indicator is a single measured number, such as the share of deaths from a cause, or the share of people with access to a service. Our WHO Global Data Explorer shows six of those figures as a dated snapshot, each with its source and year.

WHO reports that 3.6 billion people live in areas highly susceptible to climate change, and that climate change is expected to cause about 250,000 additional deaths per year between 2030 and 2050 from undernutrition, malaria, diarrhoea and heat stress.

The causes behind the numbers

Read What causes climate change? for the causes behind those numbers.

For the COP process itself — the declaration, the NDCs, the Belém plan and the scorecard — see Climate and health: COPs, NDCs and plans. For the current conference, see COP31 and health: Health Day 2026.

Almost the whole world population — 99% — breathes air that exceeds WHO guideline limits, and air pollution is linked to about 7 million premature deaths each year (WHO).

Check a published reading

The Air Quality Index Lookup shows a published reading for a place, and the UV Index Lookup shows the published UV index with the WHO scale bands.

Life expectancy differs widely between countries.

What moves it

What moves it is not one factor but many: income, education, health systems, living conditions and the environment.

The global figure

WHO’s Global Health Estimates put global life expectancy at 73.3 years in 2023, close to the 73.4 years recorded in 2019 before the pandemic. These are population figures; they describe groups, not any individual’s future. Read the full guide: Life expectancy by country. For the years lived in full health — and the gap between the two numbers — see Life expectancy vs healthy life expectancy.