A new study published in Nature Medicine shows that nearly 40% of cancer cases worldwide could be prevented by addressing three major risk factors: tobacco use, infections, and alcohol consumption.

The study, conducted by the World Health Organization and its International Agency for Research on Cancer (IARC), analyzed global cancer data from 185 countries and matched it with exposure data for 30 modifiable risk factors. Researchers found that in 2022, 7.1 million new cancer diagnoses were linked to these factors.

Tobacco accounted for 15% of cases, infections for 10%, and alcohol for 3%. Lung, stomach, and cervical cancers represented nearly half of cases associated with modifiable risks, with infections caused by human papillomavirus (HPV), hepatitis B and C, and Helicobacter pylori contributing significantly. Cigarette smoking was also linked to lung, throat, and gastrointestinal cancers, while alcohol was tied to breast, liver, colon, and throat cancers.

Study author Hanna Fink emphasized that many cancers are preventable. “Almost four in 10 new cancer cases worldwide…were linked to things we can change or modify through awareness and public-health action,” she said. The study highlighted additional modifiable factors, including excess body weight, air pollution, and ultraviolet radiation.

Researchers recommend stronger prevention strategies targeting tobacco use, infections, alcohol consumption, and unhealthy body weight to substantially reduce global cancer cases. Governments and communities are encouraged to implement policies such as higher tobacco and alcohol taxes, smoke-free environments, health warnings, cleaner air initiatives, vaccination programs, and accessible cancer screening. Individuals can complement these measures by adopting healthier lifestyles and utilizing preventive services.

The IARC offers practical guidance to minimize risk: avoid smoking or seek help to quit, limit alcohol intake, maintain a healthy body weight with a balanced diet and regular exercise, increase daily movement, and use vaccinations like HPV and hepatitis B. Family physicians stress the importance of routine screenings, consistent sleep, and other daily habits in reducing cancer risk.

The study acknowledges limitations, including reliance on data from 2012 due to cancer latency periods, incomplete data in some low- and middle-income countries, and consideration of only 30 risk factors with strong global evidence. Researchers note that their estimate of nearly 40% preventable cancers is likely conservative, as other potential causes, such as diet, could not be robustly included.

Overall, the findings reinforce that behavioral changes at both individual and population levels can significantly reduce the global burden of cancer.