A Surprisingly Large Number of Cancer Cases Could Be Preventable

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Smoking topped the list of risk factors. But several other common issues are at fault, researchers found.

We’ve always known that a lot of cancers are preventable with early screenings and lifestyle changes, but the amount of diagnoses that could be avoided is now clearer than ever. A recent large-scale study has found that about 40 percent of cancer cases could be caused by preventable risk factors. And many of these factors, which are thought to contribute to several forms of cancer, are distressingly common.

Here are the worst culprits and more on this revealing research.

Cancer and “potentially modifiable risk factors”

In a paper published this week in the American Cancer Society’s journal, researchers estimate that 40 percent of new cancer cases in people 30 and older are linked to “potentially modifiable risk factors,” things like smoking, drinking, lack of exercise, and consuming red meat. The researchers analyzed data from 2019 and found that these habits were tied to 713,340 cases and 262,120 deaths.

The leading risk factor was — no surprise here — smoking cigarettes. About 19 percent of cases — mostly lung cancer — were attributable to smoking. The second largest contributor was excess body weight, linked to 7.6 percent of cases and mainly cancers of the endometrium, gallbladder, esophagus, liver, and kidney. 

Alcohol and cancer risk

Alcohol consumption was the third largest threat and was linked to about 5 percent of cases. Researchers determined drinking was associated with seven cancers: oral cavity, pharynx, larynx, colorectal, and female breast.

Nutritionist Emily Bucholtz, the oncology dietitian at NewYork-Presbyterian/Weill Cornell Medical Center, told us why booze can increase your risk for these diseases: “When you drink alcohol, your body breaks it down into a chemical called acetaldehyde. When we digest that, it creates an inflammatory response. That inflammation creates DNA damage — the more DNA damage we create in our body, the higher likelihood of cancer cell development.”

To reduce your risk, the American Institute for Cancer Research recommends no more than seven drinks a week for women and no more than 14 for men.

Other cancer risk factors

After alcohol, ultraviolet radiation exposure was attributable to 4.6 percent of cases and physical inactivity was to blame for 3.1 percent, according to the study. 

Researchers determined that nearly all cases of cervical cancer were linked to HPV infection, which is easily preventable with a vaccine. 

“These findings show there is a continued need to increase equitable access to preventive health care and awareness about preventive measures,” Ahmedin Jemal, Ph.D., a senior author of the study, said in a news release. “Effective vaccines are available for hepatitis B virus, that causes liver cancer and HPV, which can cause several cancer types, including cervical other anogenital and oropharyngeal cancers.”

The study drives home another important point: that there are some simple steps you can take to protect yourself against many forms of cancer. 

“With cancer, it oftentimes feels like you have no control,” Arif Kamal, M.D., chief patient officer with the American Cancer Society, told CNN. “People think about bad luck or bad genetics, but people need to feel a sense of control and agency.”