“We now have the information to prevent cancer before it starts,” said Isabelle Soerjomataram, a cancer surveillance specialist at the International Agency for Research on Cancer (IARC). Speaking with the press, Soerjomataram and colleague Andre Ilbawi presented findings from a global study covering 36 cancer types in 185 countries, published in Nature Medicine on February 3, 2026.
The study found that 7.1 million new cancer cases in 2022 — 37.8% of the 18.7 million total — were linked to modifiable risk factors (MRFs). These include well-known causes such as tobacco and alcohol, as well as infections, overweight and obesity, air pollution, occupational exposures like asbestos, and other environmental toxins.
The researchers assessed 30 MRFs, listing tobacco, alcohol, air pollution, occupational toxins, high body mass index (BMI), insufficient physical activity, smokeless tobacco and areca nut, certain breastfeeding practices, and ultraviolet radiation (UVR). For the first time in a study of MRFs, they also included infectious agents such as hepatitis B and human papillomavirus (HPV).
HPV-caused cancers represented the largest share of preventable cancers among women worldwide, despite effective vaccines being available. Ilbawi noted vaccine hesitancy is a significant barrier. Soerjomataram contrasted countries like Australia, where cervical cancer rates are near eradication at about 5 cases per 100,000, with regions where HPV-related cancer remains high — notably Latin America and Sub-Saharan Africa.
In 2022, the Global Cancer Observatory recorded more than 63,000 cervical cancer cases in Latin America and over 30,000 deaths. Maria Paula Curado, a cancer epidemiologist at A.C. Camargo Cancer Center in Sao Paulo, said mortality is high in areas with poor HPV vaccine access and limited early treatment. Curado pointed to vaccine hesitancy driven by lack of awareness or cultural concerns — for example, fears in parts of Brazil that vaccination might encourage early sexual activity. She said some Brazilian regions have about 67% vaccine coverage, below an ideal of roughly 80%.
Including infectious agents in the analysis revealed sex differences in preventable cancers. Infections accounted for 2.7 million preventable cancer cases among women (29.7%), while behavioral risks like tobacco use drove the largest share among men, causing about 4.3 million cases (45.4%).
Lung cancer illustrates how similar risk factors can affect sexes differently. Tobacco, air pollution, and occupational exposures contributed to lung cancer in both men and women, but case numbers differed: 1,326,453 lung cancer cases in men versus 477,869 in women.
With the Global Cancer Observatory projecting cancer cases to rise by more than 50% by 2045, the study’s authors emphasized the urgent need for effective prevention strategies and argued many cases could be avoided via targeted interventions. They also stressed that prevention must address geographic, social, economic, and cultural determinants, and tailor actions for women and men across different contexts.
The study notes that 62.2% of cancer cases were not attributable to the assessed modifiable risk factors. Curado observed that an ageing population is leading to the emergence of rarer cancers with unclear risk factors and limited diagnostic or treatment standards.
Suzette Delaloge, a breast cancer and prevention specialist at Gustave Roussy, described the study as a pivotal contribution to shaping a global, data-informed approach to cancer prevention. She added that while social and structural determinants shape cancer risk, individual-level actions remain essential to reducing their impact.
The researchers concluded future prevention efforts must be multifaceted, addressing sex-specific effects and the differing social and economic realities across regions to reduce the growing global cancer burden.
Edited by: Maren Sass, Carla Bleiker