A new research review
has found that regular physical activity significantly decreases risk for 13
different types of cancer including that of the colon, breast, and lung. For the analysis, 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.
The report found
that even just a couple of hours a week of physical activity significantly
reduces individuals’ risk of cancer. And,
if you can do more, the cancer risk reduction is even greater. In the study cancer risk continued to decline
as time spent doing activity increased. Prior
research has linked exercise to reduced risk of breast and colon cancer, but
the role of activity on other types of cancer has yet to be clearly established. In this analysis in addition to breast, lung,
and colon cancer, activity significantly reduced the risk of getting cancers of
the esophagus, liver, kidney, stomach, endometrium, rectum, bladder, head and
neck, as well as leukemia and myeloma.
Activity level appears to especially moderate risk of esophageal
cancer. The study found doing regular
activity reduced risk by 46%. Activity
also had a very marked impact on lung cancer risk with a 26% reduction.
No one is
certain why exercise seems to help fend off cancer. Activity has multiple beneficial effects
that likely contribute to its cancer prevention benefits. Physical
activity reduces levels of hormones, such as estrogen, that have been linked to
different cancers, especially breast cancer.
Activity also helps control levels of insulin and insulin-like growth
factor which can promote tumor formation and growth. People who work out also tend to have lower
levels of inflammation. Their cells
appear to be subject to less oxidative stress, and are more capable of
repairing damaged DNA that might cause cancer.
What to do: Get moving!
You do not have to be a gym rat to realize the health benefits of
activity. Do what you can. Some is always better than none. Current federal activity guidelines call for
doing at least 150 minutes of moderate-intensity activity (such as brisk
walking) a week, or 75 minutes of vigorous activity (such as jogging). These recommendations are primarily based on
maintaining heart health but also good guidelines for cancer risk
reduction. How vigorous an activity is
depends on your fitness level but in general other examples of moderate
intensity exercise include walking briskly (3 miles per hour or faster), water
aerobics, bicycling slower than 10 mph, doubles tennis, and ballroom dancing. Vigorous activities include race walking,
jogging/running, lap swimming, singles tennis, aerobics, bicycling more than 10
mph, jumping rope, and hiking uphill.
Adapted from articles available at:
http://www.heart.org/HEARTORG/HealthyLiving/PhysicalActivity/FitnessBasics/Moderate-to-Vigorous---What-is-your-level-of-intensity_UCM_463775_Article.jsp#.V0dQCfkrKM8
Sources:
Moore SC, Lee IM, Weiderpass E et al. Leisure-time physical activity and risk of 26 types of
cancer in 1.44 million adults. JAMA Internal Medicine. Published online ahead of print May 16, 2016. DOI:10.1001/jamainternmed.2016.1548.
McCullough LE, McClain KM, Gammon MD. The promise of
leisure-time physical activity to reduce risk of cancer development. JAMA
Internal Medicine. Published online ahead of print May 16, 2016. DOI:10.1001/jamainternmed.2016.1521.