WHO Report: Nearly 7 Million Cancer Cases Annually Could Be Prevented Through Lifestyle and Policy Action

A landmark global analysis from the World Health Organization (WHO) and its International Agency for Research on Cancer (IARC) estimates that nearly 7.1 million new cancer cases each year could be prevented if exposure to known avoidable risks were reduced. The report, released ahead of World Cancer Day, underscores that almost four in ten cancer diagnoses worldwide stem from causes that people or societies can influence through prevention efforts.

The analysis examined data from 185 countries and covered 36 cancer types, linking cancer incidence in 2022 to exposure to 30 established risk factors. The team found that about 37% of all new cancer cases were associated with modifiable causes such as tobacco use, infectious agents, alcohol consumption, unhealthy body weight, low physical activity, ultraviolet radiation and air pollution. This approach included infection-related causes in a global estimate for the first time, offering a more comprehensive picture of preventable risk.

Tobacco use emerged as the single largest preventable factor, accounting for an estimated 15% of global cancers, primarily through smoking and inhaled carcinogens that damage DNA. It was followed by infections at around 10%, with viruses like human papillomavirus (HPV) and hepatitis B and C contributing significantly to cervical and liver cancers, respectively. Alcohol use and related liver and other cancers accounted for approximately 3% of preventable cases.

The burden of preventable cancers varied by gender and region. The report found that 45% of cancer cases in men could be tied to preventable causes, compared with around 30% in women. These differences reflect variations in risk exposure, including higher smoking rates among men in many regions. Geographical patterns also showed differences in which risk factors predominated, pointing to the need for tailored public health strategies.

Lung, stomach and cervical cancers together made up nearly half of all preventable cancers, illustrating how certain tumour types disproportionately reflect modifiable factors. Lung cancer’s prevalence correlates closely with smoking and air pollution exposure, while cervical cancer is overwhelmingly caused by HPV infection, which is largely preventable through vaccination. Helicobacter pylori infection, associated with stomach cancer, remains common in some regions and can be addressed through screening and treatment.

Researchers emphasised that although some cancers cannot be prevented due to age-related DNA damage or inherited genetic risk, a substantial share of the global cancer burden falls into a category that strong prevention policy and behaviour change could reduce considerably. The WHO analysis provides a roadmap for interventions that span tobacco control, wider vaccination programmes, safer workplaces and cleaner environments.

For example, HPV vaccination, already proven to dramatically lower cervical cancer risk, was highlighted as a powerful tool to cut future cancer rates where coverage remains low. Likewise, tobacco control policies, including taxation, advertising bans and smoke-free environments, are known to reduce smoking prevalence and related cancer risk. Increased public awareness of healthy diets, physical activity and reduced alcohol consumption also formed a core part of recommended actions.

The findings underline the value of comprehensive public health approaches that address behavioural, environmental and infection-related risks. By reducing exposure to these modifiable factors, governments and health agencies have an opportunity to spare millions of people from cancer diagnoses and deaths, while also lowering healthcare costs and improving quality of life.

The report coincides with World Cancer Day, an annual global event observed on 4 February to promote cancer awareness and prevention efforts. It reinforces the message that many cancers are not inevitable and that coordinated action across sectors and societies could markedly reduce the global cancer burden in the decades ahead.

Implementing effective prevention measures — including robust tobacco control, expanded vaccination against cancer-causing infections, measures to reduce air pollution, and strategies to support healthier lifestyles — could transform global health outcomes. The WHO and IARC call for sustained investment and policy commitment to support these efforts, particularly in regions with high rates of preventable cancers.