Up to four in every ten new cancer cases worldwide can be prevented through lifestyle changes, stronger public health policies and early interventions, the World Health Organisation (WHO) has said.
The warning is contained in a new global analysis released on World Cancer Day, February 4, 2026, drawing attention to the growing burden of cancer and the urgent need for prevention-focused health strategies, particularly in low- and middle-income countries such as Nigeria.
The findings are based on a Nature Medicine study analysing cancer data from 185 countries across 36 cancer types, and show that about 37 per cent of the 18.7 million new cancer cases recorded globally in 2022 were linked to modifiable risk factors.
According to the WHO, the most significant preventable drivers of cancer include tobacco use, infectious agents, unhealthy diets, physical inactivity, alcohol consumption and environmental pollution.
“The science is clear,” said Dr Maria Neira, WHO Director of Environment, Climate Change and Health.
“A large proportion of cancers — particularly those linked to tobacco, infections and unhealthy environments — are not inevitable. They are preventable.”
Tobacco, Infections Lead Preventable Cancer Causes
The report identifies tobacco use as the single largest preventable cause of cancer globally, responsible for around 15 per cent of all new cases. This includes cancers of the lung, throat, mouth, oesophagus and bladder.
Infectious agents such as human papillomavirus (HPV) and Helicobacter pylori together account for about 10 per cent of new cancer cases, particularly cervical, liver and stomach cancers.
“Smoking and infection-associated cancers continue to take an enormous toll,” said Dr Elisabete Weiderpass, Director of the International Agency for Research on Cancer (IARC), an arm of the WHO.
“Effective prevention is not only possible — it must be prioritised.”
Why This Matters For Nigeria
Health experts say the findings are especially relevant for Nigeria, where late diagnosis, limited screening programmes and weak preventive healthcare systems continue to fuel rising cancer deaths.
Cancers linked to HPV, hepatitis, tobacco use and environmental exposure remain common in Nigeria, while access to vaccines, screening and early treatment remains uneven across states.
WHO officials note that cervical cancer, one of the leading causes of cancer-related deaths among Nigerian women, is almost entirely preventable through HPV vaccination and routine screening.
Similarly, stomach cancers associated with H. pylori infection can be reduced through improved sanitation, access to antibiotics and early testing.
Gender And Regional Gaps
The WHO analysis also highlights disparities in preventable cancer burdens:
- About 45 per cent of cancers in men were linked to modifiable risk factors
- Around 30 per cent in women were attributable to preventable causes
Regional differences were also observed, reflecting variations in lifestyle, pollution levels, infection rates and access to healthcare.
“These differences show why countries need locally tailored prevention strategies,” Dr Neira said. “One-size-fits-all solutions will not work.”
Call For Policy Action And Prevention
The WHO is urging governments to prioritise prevention over treatment, stressing that early action is cheaper, more effective and saves lives.
