Philadelphia, PA, August 28, 2012 - Many people can drop pounds quickly in the early phases of a diet, but studies have found that it is difficult to keep the weight off in the long term. For post-menopausal women, natural declines in energy expenditure could make long-term weight loss even more challenging. A new study finds that in post-menopausal women, some behaviors that are related to weight loss in the short term are not effective or sustainable for the long term. Interventions targeting these behaviors could improve long-term obesity treatment outcomes. The research is published in the September issue of Journal of the Academy of Nutrition and Dietetics.
Lead investigator Bethany Barone Gibbs, PhD, University of Pittsburgh Department of Health and Physical Activity, explains that a number of factors work against long-term weight loss. "Not only does motivation decrease after you start losing weight, there are physiological changes, including a decreased resting metabolic rate. Appetite-related hormones increase. Researchers studying the brain are now finding that you have enhanced rewards and increased motivation to eat when you've lost weight." Combined with the natural energy expenditure decline in women following menopause, it is extremely difficult for older women to lose weight and maintain weight loss.
Traditional behavioral treatments for obesity, focused on caloric intake, have had poor long-term results. The investigators sought to determine if changes in eating behaviors and selected foods were associated with weight loss at six and 48 months in a group of overweight post-menopausal women. A total of 508 women were randomized to either a Lifestyle Change group or a Health Education group. The Lifestyle Change group met regularly with nutritionists, exercise physiologists, and psychologists throughout the study. Their goals were to reduce fats and caloric intake, increase consumption of fruit, vegetables, and whole grains, and participate in regular moderate exercise. The Health Education Group was offered seminars by health professionals on general women's health, but not specifically weight loss.
Investigators found that the eating behaviors associated with weight loss at six months were eating fewer desserts and fried foods, drinking fewer sugar-sweetened beverages, eating more fish, and eating at restaurants less. After four years, they found that eating fewer deserts and drinking fewer sugar-sweetened beverages continued to be associated with weight loss or maintenance. Eating fewer desserts and drinking fewer sugar-sweetened beverages were also related to long-term weight loss. However, eating more fruits and vegetables and less meat and cheese emerged as additional important predictors for long-term weight loss. Eating at restaurants declined at 48 months whether or not subjects lost weight. Dr. Barone Gibbs speculates that this may have been related to economic factors and not relevant to the study.
Dr. Barone Gibbs explains that strategies such as eating fewer fried foods may not be sustainable for the long term. "People are so motivated when they start a weight loss program. You can say, 'I'm never going to eat another piece of pie,' and you see the pounds coming off. Eating fruits and vegetables may not make as big a difference in your caloric intake. But that small change can build up and give you a better long-term result, because it's not as hard to do as giving up French fries forever."
The results suggest that decreased consumption of desserts and sugar-sweetened beverages consistently associate with short- and long-term weight loss or maintenance, but increased fruits and vegetables and decreased meat and cheeses are additional factors that may improve long-term weight loss or control. "If the goal is to reduce the burden of obesity, the focus must be on long-term strategies because changes in eating behaviors only associated with short-term weight loss are likely to be ineffective and unsustainable," concludes Dr. Barone Gibbs.
In an audio podcast accompanying the study, Dr. Barone Gibbs discusses the results in depth, including its implications for men and women of all ages and the challenges of self-reporting in research on diets and eating behaviors.