Exercise can reduce the risk of 13 cancers, according to a study reported in the Journal of the American Medical Association.
From Forbes, reporting on a JAMA study:
It finds that people who get more activity in their leisure time have reduced risk of 13 types of the 26 types of cancer that were analyzed. The connections have largely been seen before, but this new analysis, in well over a million people, is a convincing once, since not only are the numbers are huge, but because the team breaks down the connection by type of cancer. And the size of some of the connections is striking.
Of the participants in the current study, gathered through the National Cancer Institute Cohort Consortium, 1.44 million provided information about the physical activity they did in their leisure time–walking, running, swimming and so on. Their average age was 59, and their average body mass index (BMI) was 26, meaning that many of the participants were overweight. No one had cancer at the time the study began. Over the next 11 years, give or take, about 187,000 incidents of cancer were logged.
- Gastric cardia (22% lower risk)
- Endometrial (21% lower risk)
- Myeloid leukemia (20% lower risk)
- Myeloma (17% lower risk)
- Colon (16% lower risk)
- Head and neck (15% lower risk)
- Rectal (13% lower risk)
- Bladder (13% lower risk)
- Breast (10% lower risk)
After body mass was taken into account, most of the connections still held. But certain kinds of cancer were dependent upon BMI as well–like esophageal adenocarcinoma, liver cancer, gastric cardio, kidney cancer and particularly endometrial cancer. These cancers are known to be linked to body fat (in particular to estradiol), so the finding that they were also linked in the current study isn’t so surprising. But the fact that other, non-BMI-related cancers were linked to exercise suggests, as have others before, that there are mechanisms beyond body fat that underlie the connection–like the effect of physical activity on immune function, inflammation and oxidative stress.
And remember, we’re not necessarily talking hours and hours in the gym, as this article, also from Forbes, notes.
So, get out there and enjoy your workout!