Aspirin has long been known to confer various benefits when it comes to health, and now a new study suggests the medication could lower people's overall risk of developing cancer.
According to research led by scientists at Harvard University, regular use of aspirin reduces the risk of cancer in general by 3 percent, primarily due to its effects on colorectal cancer and other tumours of the gastrointestinal tract. While scientists already knew about aspirin's impact on these particular cancers, this is the first time a study has estimated the knock-on effects on the overall risk of developing the illness.
To investigate the impact of aspirin use in a broader perspective of numerous cancers, the scientists examined two separate US studies – the Nurses' Health Study (1980–2010) and the Health Professionals Follow-up Study (1986–2012) – containing data on almost 136,000 participants over the course of 32 years.
The findings, reported in JAMA Oncology, suggest that regular use of aspirin reduces the risk of colorectal cancer by 19 percent, and the risk of any gastrointestinal cancer by 15 percent.
However, according to the researchers, there's a range of other cancers where aspirin doesn't have this kind of effect, making no observable impact on the risk of developing breast, prostate, or lung cancer.
When these other tumour types are taken into consideration, regular aspirin uses averages out to a 3 percent risk reduction overall – small perhaps, but definitely significant. The researchers estimate regular aspirin use could prevent almost 30,000 gastrointestinal tract tumours in the US annually.
So what's "regular" aspirin use, as described in the study? The researchers defined it to mean taking one standard or low-dose tablet at least twice a week. In the data, the protective benefit of the medication showed after five years of continuous use, with varying dosages – ranging from half a standard tablet to 1.5 standard tablets per week, or one low-dose tablet a day.
But while we can now estimate this risk based on a large data set, the researchers are being cautious in their medical advice as it pertains to any particular person.
"We now can recommend that many individuals consider taking aspirin to reduce their risk of colorectal cancer – particularly those with other reasons for regular use, such as heart disease prevention – but we are not at a point where we can make a general recommendation for overall cancer prevention," said epidemiologist and gastroenterologist Andrew Chan from Harvard Medical School and Massachusetts General Hospital.
"Our findings imply that aspirin use would be expected to prevent a significant number of colorectal cancers above and beyond those that would be prevented by screening and may have even greater benefit in settings in which the resources to devote to cancer screening are lacking."
In other words, taking aspirin might be a good idea for lowering your overall risk of cancer, but because everybody's different, it's important to seek out proper medical advice. There's no silver bullet, here.
After all, a person doesn't develop 'general' or 'overall' tumours. They might develop a particular type (or types) of cancer, in which case the benefits of using aspirin to complement other cancer-fighting treatments and detection methods will depend very much on the individual's body and inherent risk factors.
"At this point, it would be very reasonable for individuals to discuss with their physicians the advisability of taking aspirin to prevent gastrointestinal cancer, particularly if they have risk factors such as a family history," said Chan.
"But this should be done with the caveat that patients be well informed about the potential side effects of regular aspirin treatment and continue their regular screening tests. Furthermore, aspirin should not be viewed as a substitute for colonoscopy or other cancer screening tests."