Acceptance-Based Therapy for Weight Loss

An acceptance-based behavior approach to weight control shows promise for adherence and durable results, says Evan Forman, PhD, Professor of Psychology at Drexel University. He discussed this treatment approach as it has been used work done at Drexel during Obesity Week in Boston, MA, on November 6, 2014.

Cognitive-behavioral interventions used in standard behavior therapy (SBT) can be effective over the short term, but have not been shown to produce durable results over the long term. One key factor that weighs against long-term success is simple in adherence, meaning being unable to maintain the behaviors necessary to keep weight off. Forman cited work showing that few people are able to maintain weight loss for even one year, with almost everyone regaining weight after five years.

Other human characteristics that may impair long-term adherence to healthy eating habits include the drive for hedonic maximization and a low tolerance for distress. Overall, individuals with a low distress tolerance are less successful in maintaining weight loss and recovering from a variety of addictive behaviors. Other factors that contribute to weight regain include erosion over time of one’s commitment to healthy behaviors, and the presence of automatic decision making, when choices are made without consciously weighing options.

These behaviors, Forman explained, occur against a backdrop of evolutionarily maladaptive taste preferences. A biobehavioral explanation of obesity realizes that humans have evolved to have taste preferences for fat, sugar and salt. These preferences are now maladaptive in a modern food environment with easy access to a wide variety of high-calorie food.

Acceptance-based therapy (ABT) encourages a mindful but nonjudgmental approach to give participants the tools to note, but not act on, urges to overeat or to make unhealthy food choices. This strategy draws from theories of mindfulness. Participants are encouraged to note cues as they occur, but are encouraged to be willing to choose an action that might not reduce unpleasant sensations (choosing not to eat despite feeling hungry, for example). Values clarification exercises help participants define personal goals and values, and to see how short-term distress avoidance may undermine long-term goals.

Forman reviewed his recently completed randomized controlled trial of acceptance-based treatment compared with standard behavior therapy (SBT), which enrolled 128 subjects who participated in 30 treatment sessions over a 40-week period, and then were followed for an additional six months after study completion. Study participants were mostly female, with a mean age of 45.7 and a mean BMI of 34.1 kg/m2. Some of the interventionists who provided treatment in each arm were experts (PhDs with extensive experience in weight control), while some were non-experts (graduate students without experience).

Overall, there was no significant difference between weight loss for the two treatment arms either at 40 weeks or at six months. However, for participants who had high scores for depression, emotional eating, disinhibition, and responsiveness to food, ABT produced significantly more weight loss than SBT. Analysis from a follow-on study also showed greater effect of ABT in those who were not showing early response to treatment.

Interestingly, expert interventionists offered participants in both arms a significant advantage in weight loss over non-experts, and this effect persisted at the six-month follow up.

Other studies also underway at Drexel have enrolled a total of 800 participants, with plans to intervene for as long as 78 weeks and follow patients for as long as three years. In addition to assessing durability for this treatment modality, the group plans to assess participant characteristics to make recommendations about treatment matching, so ABT can be recommended to those most likely to reap its benefits.