Want to lower your risk for colorectal cancer? This household staple may help

Just two aspirin a week may help reduce the risk of colorectal cancer in adults living unhealthy lifestyles, new research from Mass General Brigham finds.

Nearly 108,000 health professionals were included in the study — most were around 50 years old.

Researchers recorded their aspirin intake and assigned them a lifestyle score based on their body mass index, alcohol consumption, physical activity, diet and tendency to smoke cigarettes.

Regular aspirin use was defined as two or more standard tablets (325 milligrams each) or at least six low-dose pills (81 milligrams each) per week.

Participants were followed for more than three decades, with researchers documenting about 2,500 cases of colorectal cancer.

They determined that those with unhealthier lifestyles — especially if they were overweight or heavy smokers — enjoyed the greatest benefit from aspirin use compared with their healthier peers.

The unhealthy participants had a 3.4% chance of getting colorectal cancer if they did not regularly take aspirin versus a 2.1% chance if they did.

Among the healthiest participants, the colorectal cancer rates were 1.5% in the aspirin-taking group and 1.6% in the non-aspirin group.

The findings were published Thursday in JAMA Oncology.

“Our results show that aspirin can proportionally lower the markedly elevated risk in those with multiple risk factors for colorectal cancer,” said Dr. Daniel Sikavi, lead author of the paper and a gastroenterologist at Massachusetts General Hospital.

“In contrast, those with a healthier lifestyle have a lower baseline risk of colorectal cancer, and, therefore, their benefit from aspirin was still evident, albeit less pronounced,” Sikavi added.

Colorectal cancer is one of the most common cancers worldwide — an estimated 1 in 24 Americans will get it at some point, according to the Colon Cancer Coalition. It’s also one of the obesity-related diseases that’s becoming more prevalent in younger generations.

In 2016, the US Preventive Services Task Force (USPSTF) recommended adults in their 50s take low-dose aspirin every day for prevention of heart disease and colorectal cancer.

Researchers say aspirin can help the immune system identify and target cancer cells, inhibit inflammation, a risk factor for colorectal cancer, and promote the growth of beneficial gut bacteria.

However, the USPSTF amended its guidance in 2022 following research that found that older people who took a daily low dose of aspirin actually had an elevated risk of advanced cancer and death from cancer.

The task force now says people 40 to 59 years old who are at higher risk for heart disease should decide with their doctor whether to start taking aspirin. Possible downsides include an increased risk of bleeding.

This new study did not assess potential side effects of daily aspirin use, such as bleeding.

Still, the researchers hope that “health care providers might more strongly consider recommending aspirin to patients who have less healthy lifestyles.”