Regular aspirin use is associated with a reduced risk for developing colorectal cancer in older age — but you won't get the benefit if you start the therapy too late in life, according to a Harvard study published online Jan. 21, 2021, by JAMA Oncology. Researchers combined the results of two large studies involving a total of more than 94,000 people who answered health questionnaires regularly and were followed for three decades. Compared with people who didn't take aspirin, people ages 70 or older who took either 325 milligrams (mg) or 81 mg of aspirin at least twice per week had a 20% lower risk for developing colorectal cancer — but only if they had started the therapy by age 65. Starting aspirin therapy at or after age 70 was not associated with significant protection against colorectal cancer. The study was observational and does not prove whether aspirin can or cannot ward off colorectal cancer. But other observational studies have also shown an association between aspirin use and lower colorectal cancer risk. Like any medicine, aspirin isn't risk-free: regular use increases the risk for gastrointestinal bleeding. If you happen to be taking aspirin regularly for other reasons, this might be an added benefit.
Image: © Jupiterimages/Getty Images
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.