Nearly 40% of cancers are linked to three modifiable risks, study finds

A Nature Medicine analysis for 2022 estimated that nearly 40% of new global cancer cases were linked to tobacco, infections and alcohol, and the study’s authors and commentators say population-level prevention strategies could reduce that burden.

A new analysis published in Nature Medicine reports that almost four in 10 new cancer cases worldwide in 2022 were associated with a small set of changeable risks. The study was conducted by the World Health Organization and its International Agency for Research on Cancer using cancer records and exposure data across 185 countries. Researchers matched cancer incidence with 30 modifiable risk factors to estimate the share of cases linked to those exposures. Study authors and medical commentators highlighted prevention and public-health measures as central to lowering the number of avoidable cancers. Key findings: - The analysis linked about 7.1 million cancer diagnoses in 2022 to 30 modifiable risk factors. - Nearly 40% of new cases were associated with three main risks: tobacco (around 15% of cases), infections (about 10%) and alcohol (about 3%). - Lung, stomach and cervical cancers made up nearly half of the cases tied to modifiable risks, with infections such as human papillomavirus, hepatitis B and C, and Helicobacter pylori cited as contributors. - The proportion of preventable cases varied by sex and region, with the study noting roughly 45% of new cancers in men and 30% in women were linked to the included risk factors. - The researchers used older exposure data in some instances (around 2012) and limited the analysis to 30 risk factors with robust global data, so the authors called the estimate likely conservative. Summary: The study frames a substantial portion of the global cancer burden as associated with modifiable exposures and emphasizes prevention at the population level. Researchers and public-health authors recommended stronger prevention strategies — including measures addressing tobacco, infections, excess body weight and alcohol — and noted that policy and community actions influence how feasible those measures are in different countries.