Medicine cabinet check! Can we use aspirin to combat cancer?

The Bottom Line

  • Cancer is the leading cause of death worldwide and was responsible for around 10 million deaths in 2020.   
  • In people who have not previously had cancer, long-term aspirin use does not decrease the incidence of cancer or death from cancer, but does increase the risk for a major bleed. 
  • To help reduce your risk of developing cancer, sit less, exercise regularly, maintain a healthy body weight, consume a healthy diet, limit/avoid alcohol, avoid/quit smoking, and practice sun safety.

Whether from personal experience or through witnessing the journey of a loved one, we’ve all been touched by cancer in some way, shape, or form. Last year alone, around 10 million people died from cancer, the leading cause of death worldwide (1).

As cancer cases and deaths continue to rise, researchers are focused on identifying strategies that can help to prevent and treat the variety of diseases that fall under this broad term. When it comes to prevention, you may be surprised to learn that one highly debated strategy comes in the form of an over-the-counter medication that many of us have readily on hand. We use it to help get rid of headaches, relieve sore muscles, and reduce fevers. Although this generic description fits many different painkillers, aspirin is the focus of this particular conversation; just like it has been in previous discussions around heart health and dementia prevention (2-4). With aspirin popping up again as a potential preventative strategy, what will the research show this time? Can we rely on it to help us thwart cancer? A relatively recent systematic review looked at long-term aspirin use and its ability to help prevent cancer in people who have not previously had cancer (2).

What the research tells us

Similar to previous findings for stroke and death in people with no heart disease and dementia in healthy older adults, aspirin use doesn’t appear to be protective against developing cancer and continues to be associated with adverse side effects (2-4).

Overall, the review found that in people with no previous history of cancer, long-term use of aspirin (i.e., between 1 - 5 years, 5 -10 years, and over 10 years) does not reduce total cancer incidence or total cancer deaths, compared to no aspirin use. However, the use of aspirin does increase the risk of experiencing a major bleed by anywhere between 32% - 57%; and may increase total bleeding events by anywhere between 33% - 74%. The lack of benefits and presence of side effects are seen across different doses of aspirin, aspirin use duration, and populations (such as healthy people, people living with diabetes, and people with heart disease or an increased risk of heart disease) (2).

With that said, the authors of the review do note the need for more research in two areas, the first being aspirin use in higher risk populations, such as those with a family history of cancer (2). The second area is aspirin’s effects on individual types of cancer, as opposed to an overall analysis like that done in this review. This is because there is some evidence to show a potential preventive effect for specific cancers (e.g., colorectal cancer) (2; 22). Be sure to discuss your cancer risk and preventative strategies that may work best for you with your health care provider.

Although, overall, aspirin may not be an effective cancer prevention strategy, there are evidence-based lifestyle changes that we can incorporate into our daily lives to help reduce cancer risk. These include:

  • limiting our alcohol intake (a maximum of one drink a day for women and two drinks a day for men) or avoiding alcohol altogether (6-10);
  • consuming a healthy diet rich in fruits, vegetables, and fiber, and low in red and processed meats (9; 11-14);
  • sitting less and staying physically active, working our way up to least 150 minutes of moderate intensity exercise or 75 minutes of vigorous activity per week (or a combination of the two) (15-19);
  • maintaining a healthy body weight (16); and 
  • practicing sun safety by decreasing time spent in the sun, wearing clothes that protect from the sun and using sunscreen when sun exposure is unavoidable, and not using tanning beds (20;21).

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Author Details


  1. World Health Organization. Cancer. [Internet] 2021. [cited April 2021]. Available from 
  2. Wu Q, Yao X, Chen H, et al. Long-term aspirin use for primary cancer prevention: An updated systematic review and subgroup meta-analysis of 29 randomized clinical trials. J Cancer. 2020; 11:6460-6473.  
  3. Mahmoud AN, Gad MM, Elgendy AY, et al. Efficacy and safety of aspirin for primary prevention of cardiovascular events: A meta-analysis and trial sequential analysis of randomized controlled trials. Eur Heart J. 2019; 60:607-617. doi: 10.1093/eurheartj/ehy813.  
  4. Jordan F, Quinn TJ, McGuinness B, et al. Aspirin and other non-steroidal anti-inflammatory drugs for the prevention of dementia. Cochrane Database Syst Revs. 2020; 4:CD011459. doi: 10.1002/14651858.CD011459.pub2.  
  5. Song M, Giovannucci E. Preventable incidence and mortality of carcinoma associated with lifestyle factors among white adults in the United States. JAMA Oncol. 2016; 2(9):1154-1161.
  6. Secretan B, Straif K, Baan R, et al. A review of human carcinogens – Part E: Tobacco, areca nut, alcohol, coal smoke, and salted fish. Lancet Oncol. 2009; 10(11):1033-1034.
  7. International Agency for Research on Cancer. IARC monographs on the evaluation of carcinogenic risks to humans. Lyon (FR): International Agency for Research on Cancer; 2012. 100E vol. Available from
  8. Fedirko V, Tramacere I, Bagnardi V, et al. Alcohol drinking and colorectal cancer risk: An overall and dose-response meta-analysis of published studies. Ann of Oncol. 2011; 22(9):1958-1972. doi: 10.1093/annonc/mdq653.
  9. Kushi LH, Doyle C, McCullough M, et al. American Cancer Society guidelines on nutrition and physical activity for cancer prevention. CA Cancer J Clin. 2012; 62(1):30-67. doi: 10.3322/caac.20140.
  10. World Cancer Research Fund/American Institute for Cancer Research. Food, nutrition, physical activity, and the prevention of cancer: A global perspective. Washington (DC): AICR; 2007. 537 p. Available from 
  11. International Agency for Research on Cancer. IARC Handbooks of Cancer Prevention: Fruit and vegetables. Lyon (FR): IARCPress; 2003. Available from
  12. World Cancer Research Fund/American Institute for Cancer Resarch. Continuous update report: Food, nutrition, physical activity and the prevention of colorectal cancer. Washington (DC): AICR; 2011.
  13. Bouvard V, Loomis D, Guyton KZ, et al. Carcinogenicity of consumption of red and processed meat. Lancet Oncol. 2015; 16(16):1599-600. doi: 10.1016/S1470-2045(15)00444-1.
  14. Chan DS, Lau R, Aune D, et al. Red and processed meat and colorectal cancer incidence: Meta-analysis of prospective studies. PLos One. 2011; 6(6):e20456. doi: 10.1371/journal.pone.0020456. 
  15. Biswas A, Oh PI, Faulkner GE, et al. Sedentary time and its association with risk for disease incidence, mortality, and hospitalization in adults: A systematic review and meta-analysis. Ann Intern Med. 2015; 162(2):123-132. doi: 10.7326/M14-1651.
  16. World Cancer Research Fund International/American Institute for Cancer Research. Food, nutrition, physical activity, and the prevention of cancer: A global perspective. Washington DC: AICR, 2008. Available from
  17. Ballard-Barbash R, Friedenreich CM, Courneya KS, et al. Physical activity, biomarkers, and disease outcomes in cancer survivors: A systematic review. J Natl Cancer Inst. 2012; 104(11):815-840. doi: 10.1093/jnci/djs207.
  18. Cormie P, Zopf EM, Zhang X, et al. The impact of exercise on cancer mortality, recurrence, and treatment-related adverse effects. Epidemiol Rev. 2017; 39:71-92. doi: 10.1093/epirev/mxx007.
  19. Winzer BM, Whiteman DC, Reeves MM, et al. Physical activity and cancer prevention: A systematic review of clinical trials. Cancer Causes Control. 2011; 22(6):811-826. doi: 10.1007/s10552-011-9761-4.
  20. World Health Organization, International Agency for Research on Cancer. IARC Handbooks of Cancer Prevention: sunscreens. Lyon (FR): World Health Organization & International Agency for Research on Cancer; 2001. 5 vol. Available from
  21. Colantonio S, Bracken M, Beecker J. The association of indoor tanning and melanoma in adults: Systematic review and meta-analysis. J Am Acad Dermatol. 2014; 70(5):847-857. doi: 10.1016/j.jaad.2013.11.050.
  22. Rothwell PM, Wilson M, Elwin CE, et al. Long-term effect of aspirin on colorectal cancer incidence and mortality: 20-year follow-up of five randomised trials. Lancet. 2010; 376: 1741-50.

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