Research Shows That The Risk Of Seven Types Of Cancer Can Be Lowered By Recommended Physical Activity Or Exercise Levels
A collated analysis of nine prospective studies involving more than 760,000 adults finds that recommended amounts of leisure-time physical activity
were linked to a lower risk for seven cancers
, with several cancer types having a 'dose/response' relationship.
The research study was led by investigators at the National Cancer
Institute, the American Cancer
Society, and the Harvard T.H. Chan School of Public Health and appears in the Journal of Clinical Oncology
Although it's long been known that physical activity
is associated with a lower risk of several cancers
, less clear has been the shape of the relationship and whether recommended amounts of physical activity
are associated with lower risk.
New updated guidelines for activity now state that people should aim for 2.5 to 5 hours/week of moderate-intensity activity
or 1.25 to 2.5 hours/week of vigorous physical activity
. Moderate-intensity activities are those that get you moving fast enough or strenuously enough to burn off three to six times as much energy per minute as sitting quietly (3 to 6 METs). Vigorous-intensity activities burn more than 6 METs.
In the new report, investigators pooled data from nine prospective cohorts with self-reported leisure-time physical activity
and follow-up for cancer
incidence, looking at the relationship between physical activity with incidence of 15 types of cancer.
The researchers found engaging in recommended amounts of activity (7.5 to 15 MET hours/week) was associated with a statistically significant lower risk of seven of the 15 cancer
types studied, with the reduction increasing with more MET hours.
Physical activity was associated with a lower risk of colon cancer
in men (8% for 7.5 MET hours/week; 14% for 15 MET hours/week), female breast cancer
(6%-10%), endometrial cancer
(10%-18%), kidney cancer
(11%-17%), myeloma (14%-19%), liver cancer
(18%-27%), and non-Hodgkin lymphoma (11%-18% in women). The dose response was linear in shape for half of the associations and nonlinear for the others.
The research analysis had some limitations: Even with more than 760,000 participants, patient numbers were limited for some cancers
; participants were primarily white; there was a limited number of cohorts with detailed physical activity measures; and the authors relied on self-reported physical activity.
The researchers conclude: "These findings provide direct quantitative support for the levels of activity recommended for cancer prevention and provide actionable evidence for ongoing and future cancer
Dr Alpa Patel, Ph.D., senior
scientific director of epidemiology research at the American Cancer Society told Thailand Medical
News, "Physical activity guidelines have largely been based on their impact on chronic diseases like cardiovascular disease and diabetes. These data provide strong support that these recommended levels are important to cancer
prevention, as well."
The American Cancer Society is planning to use the date from this study to educate people about the importance of incorporating physical activity and exercise into their daily health regimen.
Reference : Amount and Intensity of Leisure-Time Physical Activity and Lower Cancer Risk, Matthews et al. Journal of Clinical Oncology (2019). DOI: 10.1200/JCO.19.02407