New research suggests taking aspirin regularly can significantly reduce cancer risk, and these benefits could outweigh the negative consequences associated with the drug.

For the first time in history researchers reviewed all of the available evidence on the benefits and consequences of preventative aspirin use, Queen Mary, University of London. The findings were published in a recent edition of the Annals of Oncology.

The research team found taking aspirin every day for 10 years could cut bowel cancer by about 35 percent and related deaths by 40 percent. Rates of esophageal and stomach cancers were also cut by 30 percent and instances of death by between 35 and 50 percent.

To achieve these benefits the researchers determined one would need to start taking a daily dose of between 75 and 100 milligrams of aspirin for at least five years (and most likely 10) between the ages of 50 and 65. No benefit from aspirin was observed during the first three years of use.

Long-term aspirin use can increase the risk of bleeding in the digestive tract. In individuals over the age of 60 who took aspirin every day rates of stomach bleeding increased from 2.2 percent to 3.6 percent; this condition could be life threatening to about five percent of the people it affects. Aspirin can also cause peptic ulcers, the risk of which are increased by 30 to 60 percent.

The findings suggest if everyone between the ages of 50 and 65 were on an aspirin regimen the rate of cancers, strokes, and heart attack would be reduced by nine percent in men and about seven percent in women. The side effects of the drug are more dangerous for those over 70, so the recommendation does not stretch into that age group.  

"It has long been known that aspirin - one of the cheapest and most common drugs on the market - can protect against certain types of cancer. But until our study, where we [analyzed] all the available evidence, it was unclear whether the pros of taking aspirin outweighed the cons," said Professor Jack Cuzick, Queen Mary University of London."Whilst there are some serious side effects that can't be ignored, taking aspirin daily looks to be the most important thing we can do to reduce cancer after stopping smoking and reducing obesity, and will probably be much easier to implement.