Nearly 40% of Cancers Are Preventable, WHO and IARC Report Finds

Almost four in ten cancer diagnoses could be prevented, according to a latest report by the World Health Organization (WHO) and the International Agency for Research on Cancer (IARC). The analysis, based on 2022 data from 185 countries, highlights the significant impact of preventable risk factors, particularly smoking and alcohol consumption, on the global cancer burden.

The Scale of Preventable Cancers

The report identified 30 exposure factors linked to cancer development and estimated that 7.1 million cancer cases registered in 2022 – representing 37% of all new diagnoses worldwide – were attributable to preventable causes. Experts emphasize that modifying certain behaviors and implementing robust public health policies could substantially improve outcomes.

Smoking: The Leading Preventable Risk Factor

Smoking remains the most significant preventable risk factor for cancer, accounting for approximately 15% of all new cancer cases globally. The impact extends beyond lung cancer, with tobacco use linked to cancers of the bladder, kidney, liver, and pancreas, among others. Carcinogens from inhaled smoke circulate through the bloodstream, affecting multiple organs. IARC continues to research the impact of tobacco.

Research shows that quitting smoking, even after a cancer diagnosis, can reduce the risk of cancer progression or death by half. IARC supports the WHO’s #TobaccoExposed campaign.

Alcohol Consumption: A Direct and Cumulative Risk

Alcohol consumption is another key preventable risk factor, associated with 3% of new cancer diagnoses worldwide. The risk increases with greater alcohol intake, and the report indicates there is no completely safe level of consumption. Alcohol can damage tissues and enhance the action of carcinogens in areas like the mouth, throat, esophagus, liver, and colon.

The WHO notes that alcohol consumption is increasing in several low- and middle-income countries, potentially impacting future cancer rates.

The Importance of Public Health Policies

The study, led by André Ilbawi of the WHO, underscores the importance of quantifying the portion of cancer risk arising from controllable causes. Ilbawi emphasized that individual decisions, such as quitting smoking or moderating alcohol consumption, must be complemented by strong public health policies, including regulation, prevention campaigns, and access to evidence-based information.

Looking Ahead

While cancer is a complex and multifactorial disease, a substantial proportion of cases are linked to modifiable habits. Changing behaviors doesn’t eliminate risk entirely, but it can significantly reduce the overall impact of the disease. Continued research and proactive public health measures are crucial in the ongoing effort to prevent cancer worldwide. IARC published a study on February 17, 2026, about avoidable deaths through cancer prevention.