When it comes to shedding unwanted pounds—weight and body fat—post-menopausal women who diet and do aerobic exercise together get the most bang for their buck, according to a new study by Fred Hutchinson Cancer Center.
The majority of women in the study who improved their diet and exercised regularly were the biggest losers, shedding an average of nearly 11 percent of their starting weight, which exceeded the study's goal of a 10 percent reduction.
Ann McTiernan, M.D., Ph.D., director of the Prevention Center and a member of the Hutchinson Center's Public Health Sciences Division, led the year-long study involving 439 overweight-to-obese, sedentary, postmenopausal Seattle-area women, ages 50 to 75.
McTiernan said postmenopausal women were the focus of the study since that’s a group that experiences particularly high rates of overweight and obesity.
“We were surprised at how successful the women were," McTiernan said. "Even though this degree of weight loss may not bring an obese individual to a normal weight, losing even this modest amount of weight can bring health benefits such as a reduced risk of diabetes, heart disease and many types of cancer.”
Study participants were randomly assigned to one of four groups: an exercise-only group, diet-only group, diet and exercise group, and a no intervention group. At the end of the intervention, the researchers found the women in the exercise-only group lost, on average, 4.4 pounds as compared to an average weight loss of 15.8 pounds among women in the diet-only group. The non-intervention group on average lost less than a pound – a statistically insignificant decrease.
Women who reducing calories by cutting fat intake and boosting the consumption of low-calorie foods and did moderate-intensity aerobic exercise regularly achieved the greatest weight loss. On average, these women shed an average of 10.8 percent of their starting weight (with a mean weight loss of 19.8 pounds). Two-thirds of the women in this group achieved the study goal of losing at least 10 percent of their starting weight.
McTiernan says you don't need to be an athlete to get the exercise you need. The women in the study walked, biked or used gym cardio machines. “Start slowly and gradually increase to 45 minutes of activity a day, more if you are able,” she said.
Apart from the weight loss, women in the three intervention groups saw their body-mass index (height-to-weight ratio), waist circumference and percentage of body fat significantly reduced.
The study also found that the women who lost the most weight and body fat kept a food journal, writing down everything they ate and drank with the exception of water and no-calorie drinks. Other strategies associated with the most successful weight loss included preparing meals at home and eating out less often at restaurants. “Doing your own cooking gives you the most control over calories,” McTiernan said.
In addition to promoting weight loss and preventing weight gain over time, regular exercise helps with balance, strength and fitness. "Exercise helps older people keep active overall, which has been shown to prolong a healthy life," McTiernan said.
Lynette Summerill is an award-winning writer who lives in Scottsdale, Arizona. In addition to writing about cancer-related issues for EmpowHER, her work has been seen in newspapers and magazines around the world.