Bewegen
en gezonde voeding tegen
kanker*
Uit een studie blijkt dat het merendeel van de mensen niet op de hoogte is van een belangrijke oorzaak voor het ontstaan van
darmkanker, een oorzaak die makkelijk te verhelpen is. Mensen die hoofdzakelijk een zittend bestaan hebben tekenen voor 14% van alle darmkanker gevallen. Regelmatig
bewegen doet het risico op darmkanker met wel 30-40% verminderen.
Een
andere studie laat zien dat regelmatig bewegen de kans op longkanker flink kan
verminderen. Rokers verminderen hun kans op longkanker met 33% door regelmatig
te bewegen. Voor ex-rokers is dat 45%. Als men ook nog eens veel groenten deed
eten verminderde kans op longkanker bij rokers wel met 71% en bij ex-rokers met
67%.
Awareness of the role of physical activity in colon cancer prevention
Many experts now consider colon cancer a largely preventable disease, but a new study finds that primary care doctors might not always inform patients about one important step they can take to reduce their risk: becoming more physically active.
When researchers analyzed survey data from 1,932 adults who answered questions about colon cancer risks, only 15 percent listed physical activity as a means of reducing their risk.
Yet a sedentary lifestyle accounts for as many as 14 percent of all colon cancer cases in the United States. Highly active individuals have a 30 percent to 40 percent lower risk of developing colon cancer, according to the researchers.
Several factors contribute to the information gap, according to study co-author Elliot Coups. "Patients may not be learning this information from their health care providers and information regarding colon cancer prevention is not as well publicized as it could be."
The study appears in the journal Patient Education and Counseling.
Doctors might find it easier to promote the general benefits of exercise, without specifically mentioning colon cancer, even to a patient who has a family history or has other risk factors, said Coups, at the Division of Population Science at the Fox Chase Cancer Center in Cheltenham, Pa.
"In the context of busy clinic visits, it is in some ways efficient for patients to be reminded that physical activity is good for their health in general," Coups added. "Going through each specific health benefit of physical activity would take considerable time."
Doctors might also need to offer more information about what it means to be physically active, as patients could imagine it involves dramatic lifestyle alterations, he said.
There is a strong benefit in going from completely sedentary to some modest levels of activity, such as walking two to three hours a week or gardening, said Edward Giovannucci, M.D., a professor at the Harvard School of Public Health. "Sedentary people should first set such moderate, achievable goals. More benefits could accrue from higher levels and more intense exercise, such as jogging, running or tennis. To some extent, more may be better, but it is important to note that a little is much better than nothing."
Because studies might skew toward cultural norms and 40 percent of Americans never engage in leisure time physical activity, inactivity could be a factor in over 14 percent of the estimated 112,000 cases of colon cancer diagnosed each year, Giovannucci said.
"While many people are vaguely aware that exercise is good, the idea that exercise specifically prevents a large proportion of a common cancer may make an impact on the patient," he said.
By Joan Vos MacDonald, Contributing Writer
Health Behavior News Service
Coups EJ, Hay J, Ford JS. "Awareness of the role of physical activity in colon cancer prevention." Patient Educ Couns 71(2), 2008.
http://www.hbns.org
Exercise Slashes Lung Cancer Risk by 45 Percent in Former Smokers
Physical exercise can decrease the risk of developing lung cancer by up to 45 percent in former smokers, while proper diet can decrease it even further, according to research presented at the American Association for Cancer Research's Sixth Annual International Conference on Frontiers in Cancer Prevention Research in Philadelphia.
Researchers studied 3,800 non-Hispanic white women and men using a pairing system that sorts people according to smoking status. Therefore, smokers with lung cancer would only be compared to smokers without lung cancer, with the same pairing taking place for former smokers and those who have never smoked. Researchers compared those who had not developed lung cancer based on a variety of factors including exposure to secondhand smoke, dust exposure, family cancer history, personal respiratory history, diet and exercise.
Exercise was determined based on whether the participants gardened or not. According to researcher Michele Forman, "gardening is one of the few activities that people with lung cancer report doing."
Former smokers who gardened reduced their lung cancer risk by 45 percent, while current smokers who gardened reduced their risk by 33 percent. Former smokers who gardened and who also ate four or more salads per week reduced their risk by 67 percent. Among current smokers, the risk reduction from both gardening and high salad intake was 71 percent.
According to Forman, salad consumption "is a marker for consumption of many
vegetables."
"We are trying to understand what components of lifestyle can reduce lung cancer risk in people who have quit smoking, which has been a neglected field of study," Forman said. She noted that further research is needed to make sure that exercise from gardening is actually the cause of the correlation, rather than gardening being associated with some other risk-reducing factor, such as low alcohol
consumption. (September
2008)
