Exercise may significantly reduce risk for many types of cancer, including some of the most lethal forms of the disease, a study says.
Working out for even a couple of hours a week appears to shrink the risk of breast, colon and lung cancer, said researchers who looked at 1.4 million adults, Health news reported.
“Those are three of the four major cancers that affect Americans today,” said Marilie Gammon. She is a professor of epidemiology with the University of North Carolina at Chapel Hill Gillings School of Public Health.
“The more activity, the more the benefit,” Moore said. “As people did more, their risk continued to lower.”
In the study, regular exercise wound up being linked to a reduced risk of 13 cancers in all, the researchers said. The others were leukemia, myeloma and cancers of the esophagus, liver, kidney, stomach, endometrium, rectum, bladder, and head and neck.
The researchers pooled data from 12 U.S. and European studies to create a database of 1.4 million adults, aged 19 to 98. They then examined whether self-reported physical activity made a difference in risk of 26 cancers.
Exercise was associated with a reduced risk for half of the cancers considered by the investigators, and that reduction remained significant for nearly all, even after accounting for factors such as obesity and smoking history.
Overall, a higher level of physical activity was associated with a 7 percent lower risk of total cancer, the researchers reported.
The range of reduced risk ran from 42 percent for esophageal cancer to 10 percent for breast cancer, the study authors said. For colon and lung cancer, risk was lowered 16 percent and 26 percent, respectively, the findings suggested.
“This suggests that physical activity may have a role to play in population-wide cancer prevention efforts,” Moore said.
