The data for the study was extracted from data from the Women’s Health Study, which has been tracking more than 30,000 women age 45 and older. For this part of the study half of whom were randomized to take aspirin every other day, while the other half received a placebo. There were 16,913 women in the aspirin group and 16,769 women in the placebo group, according to Health Day.
The study was funded by the funded by the U.S. National Cancer Institute and U.S. National Heart, Lung, and Blood Institute.
Interestingly, at the 10-year mark of the study there was no difference in the risk of cancer between those taking aspirin and those taking placebo. However, towards the end of the study, at eighteen years, a difference in cancer rates was apparent.
Talking to NBC, Nancy Cook, the lead author of the study, said: “This study provides some surprising new information since it wasn’t thought that such a low dose, especially every other day, would have an effect on cancer.”
The study has been published in the Annals of Internal Medicine. The paper is titled “Alternate-Day, Low-Dose Aspirin and Cancer Risk: Long-Term Observational Follow-up of a Randomized Trial.”
Drugs like aspirin can have side-effects like gastrointestinal bleeding. People taking any form of painkiller over the long term should discuss the matter with their doctor.