A new global analysis by the World Health Organisation (WHO) says up to four in every ten new cancer cases could be prevented through behavioural changes, stronger public policies and sustained public health action.
The findings, released this week to mark World Cancer Day on 4 February 2026, are based on a Nature Medicine study that analysed data from 185 countries covering 36 cancer types.
According to the report, about 37 per cent of the 18.7 million new cancer cases recorded worldwide in 2022 were linked to modifiable risk factors, including tobacco use, infections and lifestyle-related exposures.
“The science is clear,” said Dr Maria Neira, WHO Director of Environment, Climate Change and Health. “A large proportion of cancers — especially those associated with tobacco, infections and unhealthy environments — are not inevitable. They can be prevented.”
The report identified tobacco as the single largest preventable cause of cancer, responsible for about 15 per cent of new cases globally. Infectious agents such as human papillomavirus (HPV) and Helicobacter pylori accounted for roughly 10 per cent of cases.
“Smoking and infection-related cancers continue to exact a heavy toll,” said Dr Elisabete Weiderpass, Director of the International Agency for Research on Cancer (IARC), a WHO agency. “Effective prevention is not just possible — it is essential.”
The analysis highlighted cervical cancer as one of the most preventable forms of the disease, noting that it is largely caused by HPV, for which safe and effective vaccines are available. Cancers linked to H. pylori infection were also identified as preventable through improved sanitation, early detection and treatment.
“We are at a point where proven public health interventions — including HPV vaccination, tobacco control and healthier environmental policies — could save millions of lives,” Dr Weiderpass said.
The report revealed notable differences in preventable cancer burdens by sex and region. Among men, about 45 per cent of cancers were linked to modifiable risk factors, compared with around 30 per cent among women. Regional variations were also observed across East Asia, Latin America, North Africa and West Asia.
“These differences reflect variations in lifestyle, environmental exposure and access to preventive care,” Dr Neira said, stressing the need for locally tailored prevention strategies.
The WHO called on governments and health systems to prioritise cancer prevention by expanding tobacco taxation and smoking bans, improving air quality, increasing vaccination coverage and strengthening public awareness.
“We must move upstream,” Dr Neira said. “Investing in prevention saves lives, reduces long-term healthcare costs and builds more resilient health systems.”
The report concludes that although cancer remains a major global health challenge, nearly 40 per cent of cases could be avoided through decisive public health action, strong political commitment and community engagement.