Middle-aged guys who stay in shape are apparently less likely to end up either lung or colon cancer compared to their out-of-shape counterparts. According to a new study published March 26 online in JAMA Oncology, even if they do develop cancer they have a better chance of beating it.
Close to 14,000 men were tested by treadmill performance at middle-age, and later on their medical records were examined after they reached the age of 65 or older.
What the researchers discovered was that the guys who were in better shape had about half the risk for both colon and lung cancer compared to those who weren’t as fit. Their risk of dying from those types of cancers were about 30% lower as well.
According to assistant professor of medicine at the University of Vermont and lead researcher Dr. Susan Lakoski, those men who are physically fit are expected to have stronger immune systems, less inflammation and lower levels of cancer-related sex hormones.
“These effects may act together to inhibit cancer as well as risk of dying from cancer or heart disease,” she said.
The information used by Lakoski and her research team was collected from fitness assessments gathered from 1971 to 2009 (with men’s average age of 49) and Medicare data from 1999 to 2009 (with men’s average age of 65).
When the numbers were crunched, researchers found the following statistics:
- 1,310 out of the almost 14,000 men developed prostate cancer, 200 were diagnosed with lung cancer, and 181 men with colon cancer.
- The fittest of the men were 55% less likely to develop lung cancer and 44% less likely to be diagnosed with colon cancer when compared with their not-so-fit counterparts.
- The more physically fit guys also showed a 32% greater survival rate if they did in fact develop lung, colon or prostate cancer.
Researchers were surprised to find, however, that there was no difference in the risk of developing prostate cancer with the more in-shape men. Lakoski theorizes that health-conscious guys may be more likely to have regular check-ups, therefore increasing the likelihood of discovering prostate cancer early on.
She stresses that fit men who developed prostate cancer in this study had a higher survival rate with cancer and cardiovascular disease. “This speaks to the importance of being fit in midlife to improve survival, even if a man ultimately develops lung, prostate or colorectal cancer,” she says.
Dr. Lakoski wants to be clear that this study currently only demonstrates an association between fitness and cancer protection, but that doesn’t necessarily mean that one is responsible for the other. She stresses the importance of additional research of these results in both men and women, involving all types of cancer.
Additionally, how much of a fitness change may be needed to receive any cancer protection benefits should also be addressed.
One observation pointed out in the study is that while the correlation between fitness and cardiovascular health is well-established, less is known about how behaviors in lifestyle may impact cancer risk, years or even decades later.
While the findings in this study may be news to some, epidemiologist Alpa Patel of the American Cancer Society is not surprised at all, stating that “What they found is consistent with what we know — that physical fitness is important in cancer prevention.”
Patel says that taking a patient’s heart fitness level into consideration can help to evaluate the potential risk for cancer and heart disease. She suggests that women also may benefit from breast cancer protection as a result of good physical fitness.
As far as the study’s correlation to a reduction of lung cancer in physically fit men, Patel thinks that it’s most likely simply a result of not smoking, since only 9% of the fit guys were non-smokers, compared to 31% of the less fit men who were.