Older age is the main risk factor for cancer. This largely reflects cell DNA damage accumulating over time. Damage can result from biological processes or from exposure to risk factors.
This page covers other factors with the best evidence of an association with cancer risk; this list is not exhaustive.
See our other pages for general information about cancer, or ways to reduce your risk.
View our latest cancer statistics including key stats, in-depth explanations and raw data on cancer incidence, mortality, survival, risk, and diagnosis and treatment.
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Find out more about the sources which are essential for our statistics
Lifetime risk estimates calculated by the Cancer Intelligence Team at Cancer Research UK 2023.
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Calculated by the Statistical Information Team at Cancer Research UK, 2018. Based on Brown KF, Rumgay H, Dunlop C, et al. The fraction of cancer attributable to known risk factors in England, Wales, Scotland, Northern Ireland, and the UK overall in 2015. British Journal of Cancer 2018.
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