Smoking, obesity, alcohol consumption, and physical inactivity ranked among the leading causes of preventable cancer cases according to the study, published Thursday by the American Cancer Society.

Sexually transmitted diseases also contributed to many instances of cancer, researchers found in looking at the cancer cases of U.S. adults over the age of 30. An estimated 40% of cancer cases—in both men and women—arose from changeable lifestyle choices, according to the study.

How likely are all of these things to give you cancer? Smoking was the leading risk factor, contributing to roughly one out of every five cancer cases for men and a slightly lower fraction of women’s cases, the study said.

Alcohol consumption contributed to about one in twenty cancer cases for both men and women. Excess body weight contributed to roughly one out of every 10 cancer cases for women and one out of every twenty for men. Sexually transmitted diseases contributed to about 3% of all cancer cases for men and women combined.

How many people die of cancer from these lifestyle choices? The preventable lifestyle decisions the study examined contributed to nearly half of all cancer deaths in men, according to the study. Lifestyle decisions contributed to a slightly lower fraction of women’s cancer deaths.

This story originally appeared in WORLD. © 2024, reprinted with permission. All rights reserved.