(TNND) — A new study from the World Health Organization found that over a third of new cancer cases could be prevented because of their links to lifestyle and environmental factors that can be modified.
The study looked at all new cancer cases in 2022 and estimated that 37% were linked to preventable causes such as tobacco, alcohol, weight, physical inactivity, air pollution, ultraviolet radiation, and infections.
For men, 45% of cancers were possibly preventable. In women, it was 30%.
“Addressing these preventable causes represents one of the most powerful opportunities to reduce the global cancer burden,” Dr. Isabelle Soerjomataram, senior author of the study, said in a WHO news release.
The study looked at 30 preventable causes and pegged tobacco as the leading preventable cause of cancer, globally responsible for 15% of all new cancer cases.
That was followed by infections (10%) and alcohol consumption (3%).
Three cancer types – lung, stomach and cervical cancer – accounted for nearly half of all preventable cancer cases, according to WHO.
Lung cancer was primarily linked to smoking and air pollution.
Stomach cancer was largely attributable to a common stomach infection (Helicobacter pylori).
Cervical cancer was overwhelmingly caused by human papillomavirus, for which there’s a vaccine.
Dr. Farhad Islami of the American Cancer Society said via email that the new WHO estimates are close to those previously put out by his group.
The American Cancer Society previously estimated that 40% of all cancer cases and almost half of all cancer deaths in the U.S. are attributable to potentially modifiable risk factors.
Islami pointed out some differences between American risk factors and global risk factors.
The prevalence of excess body weight is higher in the U.S., and the prevalence of cancer-causing infections is lower here compared to many other countries, he said.
Islami said it’s clear from both the previous American Cancer Society research as well as the new WHO analysis that people can substantially reduce their cancer risk by adopting a healthier lifestyle. But he said behavioral choices occur within the context of the community.
That’s where policymakers and community leaders can make a difference by addressing food deserts, tobacco control policies, and access to places people can get physical activity, like parks and safe places to walk.
Dr. Kirk Heyne, a Houston Methodist oncologist, said a tremendous amount of emphasis is put on both prevention and treatment of cancer in the U.S.
Both have their challenges.
We spend far more money on treatment after cancer is diagnosed, Heyne said. But prevention efforts that rely on people changing their lifestyles aren’t easy to implement.
Heyne said probably 85% of lung cancer cases in America are related to smoking and 15% are related to air pollution.
Kicking that habit is the most impactful thing a person can do to stack the deck in their favor for avoiding cancer, Heyne said.
But moderate exercise, such as walking briskly for two or three hours a week, and weight loss are also important prevention measures, he said.
“Simple things that are mentioned in this article are vaccinations, which are dirt cheap and are already prevention,” he said.
Vaccinations are available for cancer-causing infections such as HPV and hepatitis B.
“After that, it is followed by lifestyle changes, for which smoking is an incredible addiction to break,” Heyne said. “And I’ll argue even a harder addiction is obesity and weight gain, lack of exercise.”