BestFIT: a Personalized Weight Loss Program
Condition: Obesity
MeSH terms: Weight Loss
Study type: Interventional

Summary: 
      The purpose of this study is to learn how to personalize weight loss programs. In this
      research we will study:

        1. Whether a weight loss counselor should decide if the traditional weight loss therapy is
           working either after 3 or 7 weekly sessions of therapy and

        2. For those who haven't lost the expected amount of weight, whether it is more effective
           to add packaged meals to the traditional weight loss therapy or to change to an enhanced
           version of behavioral weight loss therapy.
    

Detailed description: 
      The US Preventive Services Task Force recommends referral to behavioral weight loss programs
      to help obese adults achieve a clinically meaningful weight loss of 8-10% of starting body
      weight. However, approximately half of participants are unable to achieve this goal. Despite
      this, a"one size fits all" approach is the norm, a major drawback because those who do not
      respond can in fact be detected early. This gap in weight loss intervention science calls for
      an adaptive intervention approach that could provide the "right treatment at the right time
      for the right person". Adaptive interventions individualize treatment through
      empirically-supported decision rules advising when and how treatments should unfold over time
      to maximize effectiveness. Sequential Multiple Assignment Randomized Trials (SMART),
      developed explicitly to build the best adaptive interventions, use experimental design
      principles to develop these decision rules. The investigators will use a SMART to
      systematically evaluate therapeutic approach and timing differences for intervening with
      those who do not respond to a behavioral weight loss program. Self-regulation challenges have
      been identified as a major adherence barrier. Two attractive options to address
      self-regulation difficulties are: 1) supplementing behavioral treatment with Meal
      Replacements (MR) which decreases the need for self-regulation; and 2) switching therapeutic
      approaches by using an enhanced version of behavioral weight loss therapy that teaches
      acceptance based behavioral skills which boost capacity for self-regulation. Additionally,
      two time points for intervening with non-responders will be evaluated: 1) 3 weeks, based on
      current weight loss trial evidence; and 2) 7 weeks, based on average time used in the
      existing stepped care literature. Adults (n=500) will be recruited and will receive
      individual behavioral weight loss treatment (BWL). Participants will be randomized to either:
      1) treatment response assessment at 3 weeks or 2) treatment response assessment at 7 weeks.
      Subjects who have lost the expected amount of weight at their assessment point, will continue
      with traditional behavioral weight loss therapy. For those who have not lost the expected
      amount of weight, we will re-randomize them to either meal replacements in addition to the
      traditional weight loss therapy or to the enhanced version of behavioral weight loss therapy.
    

Intervention name(s): Behavioral weight loss therapy; Portion-controlled meals; Acceptance-based treatment
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): All participants start with behavioral weight loss therapy which consists of 20 weekly meetings wtih a weight loss coach. Session components will include weekly weigh-in, discussion of progress and challenges and discussion of scheduled session topic. Dietary goals and physical activity goals are set. After their first session, participants are randomized to have their weight assessed at either their 3rd session or their 7th session. Both the participant and their coach are blinded to the randomization. If the participant has lost the expected amount of weight, they continue with behavioral weight loss therapy for the full 20 session.; Participants continue with behavioral weight loss therapy, but this is augmented with portion-controlled meals (PCM). Adherence to energy intake goals is facilitated by consuming pre-prepared meals specifically designed to meet caloric intake guidelines. PCMs reduce individuals' motivationally- and self-regulatory-dependent planning and decision making around eating. PCMs also serve as a "teaching tool" regarding the amount and type of food people should eat in order to produce weight loss.; Switching the therapeutic approach to an enhanced behavioral weight loss therapy teaching acceptance-based behavioral skills theoretically addresses the root problem of many weight loss challenges and boosts long-term capacity for self-regulation. Acceptance based strategies are designed to help participants identify and internalize values and lasting commitment to behavior consistent with these values. The strategies focus on increasing people's ability to forgo more pleasurable options (e.g., hedonic pleasure of food) in favor of behavior that is distinctly less pleasurable or even aversive (remaining hungry, anxious, bored). The inability to tolerate such distress is directly associated with failure of self-regulation.
Allocation: Randomized
Intervention model: Sequential Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: obesity; diet, reducing