Exercising Lowers Risk of These Cancers, Study Suggests

Hitting the recommended levels of exercise could lower the risk of developing seven forms of cancer, according to a study.

Co-author Alpa Patel, senior scientific director of epidemiology research at the American Cancer Society, told Newsweek that the results of the study, published in the Journal of Clinical Oncology, are "very encouraging."

"Simply engaging in a brisk walk for 30 minutes on most days of the week can be important for cancer prevention," she said.

Patel and colleagues looked at data from nine studies involving 755,459 adults, who reported how much they exercised. The team followed up with the participants after 10 years to see if they had developed 15 types of cancer. Each year, 1.7 million people in the U.S. are diagnosed with cancer, and more than 600,000 die.

The average person is advised to aim to for between 2.5 to 5 hours of moderate to intense activity per week, and 1.25 to 2.5 hours per week of vigorous activity. The studies revealed a link between hitting the recommended targets and lowering the risk of seven out of 15 types of cancer.

Exercise was linked with a lower chance kidney cancer, the bone marrow cancer myeloma, and liver cancer. Men who regularly worked out had a lower chance of developing colon cancer, and women had a smaller chance or having breast, endometrial and non-Hodgkin lymphoma.

However, the scientists at the National Cancer Institute, the American Cancer Society, and the Harvard T.H. Chan School of Public Health said the research was partly limited because there weren't many patients with some types of cancer in the study. Also, most participants were white. In addition, researchers relied on the volunteers telling the truth about how much they worked out, and only leisure time was included, so the team didn't capture things like walking or biking for transportation.

The authors wrote: "These findings provide direct quantitative support for the levels of activity recommended for cancer prevention and provide actionable evidence for ongoing and future cancer prevention efforts."

Patel said it has been difficult to look at the dose relationship between cancer and exercise in the past because studies had small sample sizes. "It was exciting to find that meeting current recommended levels (which are largely based on cardiovascular disease and diabetes prevention) are also important for prevention of several types of cancer," she said.

"These results add to the evidence that being physically active has benefits for prevention of many chronic conditions like cardiovascular disease, diabetes, and several types of cancer."