(RxWiki News) Some people are at higher risk of obesity because those are the genes they were dealt. But walking instead of watching TV can cut their risk of obesity in half.
Though it may seem obvious that exercising instead of couch potato lounging would ward off obesity, a recent study reveals that swapping one habit for another can even alter the extent to which your genetics have a say over whether you become obese.
"Walk briskly for an hour each day to ward off obesity."
Lead author Qibin Qi, Ph.D., a post doctorate research fellow in the Department of Nutrition at Harvard School of Public Health, and colleagues conducted a large study of men and women from the Health Professionals Follow-up Study and Nurses' Health Study, respectively.
They gathered information regarding the 4,564 men's and 7,740 women's TV watching and exercise habits for two years before each person's body mass index was measured. The body mass index is the ratio of a person's weight to their height; 30 or greater indicated obesity.
Then the researchers gathered data on the genetic predisposition of the men and women to become obese based on 32 established factors. They assigned values per amount of BMI to each factor to determine the extent to which a person's genes contributed to their BMI.
Those with high levels of exercise were 53 percent less likely to show BMI increases related to their genetic factors, and those who watched TV 40 hours a week were four times more likely to show BMI increases from their genetics than those who watched only an hour or less of TV each week.
"In our study, a brisk one-hour daily walk reduced the genetic influence towards obesity, measured by differences in BMI by half," Qi said. "On the other hand, a sedentary lifestyle marked by watching television four hours a day increased the genetic influence by 50 percent."
Because the general public cannot yet get their genome tested for a predisposition toward obesity, Qi suggested that patients' family histories may provide clues to a person's likelihood of becoming obese.
There is still little known about the genetic tendency toward obesity, according to Qi, so more research is necessary to understand how they influence a person's weight.
What is clear, is that brisk walking will reduce the likelihood that a person will become obese, and camping out in front of the television will only increase that likelihood.
The study was presented at the American Heart Association's Epidemiology and Prevention/Nutrition, Physical Activity and Metabolism 2012 Scientific Sessions.