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Globally, one half of cancer deaths are caused by potentially modifiable risk factors.

Tobacco smoking continues to be the predominant cause of cancer in most high-income countries, while infections still play a major role in many sub-Saharan African and Asian countries. The importance of excess body weight as a major risk factor for cancer continues to escalate in most parts of the world.

There are still 1.1 billion smokers worldwide and tobacco remains the single cause of the most preventable cancer deaths.

Risks of Tobacco


1.5 billion people in 55 countries are now protected by smoke-free legislation due to progress in tobacco control legislation over the last decade.

The air we breathe has become polluted with a mixture of cancer-causing substances. We now know that outdoor air pollution is not only a major risk to health in general, but also a leading environmental cause of cancer deaths.

Dr. Kurt Straif, Head of the IARC Monographs Section

Outdoor air pollution levels are highest in economically transitioning countries.

Explore Data

A substantial proportion of cancers are caused by infection in many lower-income countries. HPV vaccination is suboptimal globally, particularly in Africa, where infection prevalence is highest.