Research reportExploratory randomised controlled trial of a mindfulness-based weight loss intervention for women
Introduction
Over the last two decades levels of obesity among British and American adults have trebled (World Health Organisation, 2003). Since obesity is associated with a wide range of health problems (Must et al., 1999), it impacts not only on quality of life, but also represents a substantial economic burden. Unfortunately, weight loss is difficult to achieve and even harder to maintain. For example, it is estimated that less than 5% of those who lose weight will have maintained these losses after 4–5 years (Kramer, Jeffery, Forster, & Snell, 1989). Research suggests that this is a result of the individual failing to maintain healthy eating and exercise habits (Jeffery et al., 2000; McGuire, Wing, Klem, Lang, & Hill, 1999). Thus knowing how to lose weight is simply not sufficient, we also need to tackle the psychological processes that lead to behaviours associated with weight gain. Indeed, experts are increasingly recognising the need to address the psychological aspects of obesity (e.g., Byrne, 2002; Cooper & Fairburn, 2001; House of Commons Health Committee, 2004). Although a growing number of interventions are now incorporating components aimed at this (e.g., Cooper & Fairburn, 2001; Rapoport, Clark, & Wardle, 2000), the development of these still falls far short of that achieved in areas such as nicotine and alcohol dependence to which obesity has been compared (House of Commons Health Committee, 2004).
Interventions to effect behaviour change in obesity management often draw on Cognitive Behaviour Therapy (CBT). Such interventions generally incorporate both behavioural elements such as cue avoidance, and cognitive elements such as challenging dysfunctional thoughts (e.g., Nauta, Hosers, & Jansen, 2001; Rapoport et al., 2000). Most recently motivational interviewing techniques have been included to increase the efficacy of traditional weight loss programmes (e.g., Carels et al., 2007).
The current study explored a different approach. Recent advances in psychotherapy suggest that mindfulness-based techniques and therapies may be an effective alternative to CBT for a wide range of clinical and non-clinical problems (Bishop et al., 2004; Hayes, Luoma, Bond, Masuda, & Lillis, 2006; Hayes, Masuda, Bissett, Luoma, & Guerrero, 2004; Teasdale et al., 2000). Mindfulness can be described as a process whereby the individual observes their immediate experience using an open and non-judgemental stance (Bishop et al., 2004). Acceptance And Commitment Therapy (ACT) is a mindfulness-based therapy that has also been successfully used to treat addictive behaviours such as drug abuse and smoking. Of particular note is that in these cases ACT appeared to be as or more effective than traditional approaches when it came to the maintenance of behavioural changes (Gifford et al., 2004; Hayes et al., 2004). Given the high relapse rates amongst dieters, an ACT-based approach to weight loss may have potential.
What does ACT involve? ACT employs mindfulness strategies to target experiential avoidance. Experiential avoidance refers to attempts to avoid or control certain private events such as negative emotions, thoughts or bodily sensations (Hayes, Strosahl, & Wilson, 1999). ACT interventions draw on a variety of mindfulness-based techniques and exercises to bring about a willingness to experience difficult thoughts, feelings and sensations rather than trying to avoid or control them. In doing so, the individual is able to abandon maladaptive behaviours normally used for avoidance and control and instead focus on behaviours that move them towards valued outcomes (Hayes et al., 1999).
How might ACT apply to obesity? There is evidence to suggest that obesity is associated with both emotional eating and external eating. Emotional eating refers to a tendency to overeat in response to negative emotions such as boredom, stress and unhappiness, whilst external eating refers to a tendency to overeat in response to food-related stimuli such as the taste, sight or smell of a palatable food (Van Strien, Schippers, & Cox, 1995). Research shows that questionnaire measures of these types of eating behaviours are positively associated with BMI and obesity (Blair, Lewis, & Booth, 1990; Braet & Van Strien, 1997; Delahanty, Williamson, Meigs, Nathan, & Hayden, 2002; Hays et al., 2002, Wardle, 1987).1 Such measures have also been shown to be associated with retrospective accounts of adult weight gain (Hays et al., 2002, see also Kayman, Bruvold, & Stern, 1990) and to predict weight regain following weight loss (McGuire et al., 1999). In addition, a study by Blair et al. (1990) found significant associations between levels of emotional eating and weight loss success; successful weight control was associated with decreases in emotional eating between baseline and a 1 year follow-up and with low levels of emotional eating at both time points. In contrast, unsuccessful weight control was associated with increases between baseline and follow-up and with high levels at both time points.
It is likely that experiential avoidance is involved in both emotional and external eating behaviours. Emotional eating occurs in response to negative emotions and there is evidence to suggest that it may be an attempt to distract attention from, or alleviate, these feelings (Tice & Bratslavsky, 2000, see also House of Commons Health Committee, 2004). If this is the case, emotional eating can be viewed as a form of experiential avoidance. In contrast, external eating occurs in response to food cues and is therefore not necessarily prompted by an attempt to avoid or control negative feelings. However, where an individual is trying to lose weight, or eat healthily, and is attempting to resist overeating in response to these cues, it is likely that he or she will experience difficult thoughts, feelings and/or bodily sensations. For example, attempting to resist desert at a restaurant my elicit uncomfortable cravings. Failure to resist desert may therefore be viewed as an attempt to avoid or control these cravings and thus also a form of experiential avoidance. Since ACT directly targets experiential avoidance it may therefore be effective in bringing about reductions in emotional and external eating behaviours.
There is also evidence that bouts of overeating can be triggered by particular thoughts, for example about having broken ones diet (Ogden & Wardle, 1991). Likewise, failure to adhere to exercise and healthy eating plans may be prompted by rationalisations about, for example, being more conscientious the next day or there being exceptional circumstances that justify the relapse. An important component of ACT is cognitive defusion, helping the individual to see thoughts simply as thoughts, rather than as things that should necessarily be believed and followed. This technique helps individuals relate differently to their thoughts enabling them to choose to act in accordance with their personal values and life goals. Thus applied to the above cognitions it may help individuals refrain from bouts of overeating and adhere to exercise and eating plans.
Following recommendations for the development and evaluation of complex health interventions (Campbell et al., 2000), the aim of the current study was to conduct an exploratory trial of the effectiveness of a brief ACT-based group intervention. Given possible sex differences in psychological determinants of weight gain and loss, with females potentially engaging in more emotional eating than males (Tanofsky, Wilfey, Spurrell, Welch, & Brownell, 1997; Wardle et al., 1992, Wardle, 1987), the trial was restricted to females only.
Section snippets
Sample size and recruitment
The target sample size was 60. There were no studies directly comparable to the present research but given attrition rates and effect sizes obtained in previous analogous investigations it was estimated this would provide an acceptable level of statistical power.
Participants were recruited by the third author (JI) via advertisements and articles in local newspapers, community and leisure centres, and on the university website. Eligibility criteria were a BMI of over 20 (this cut-off was
Baseline characteristics
Comparison of quantitative questionnaire measures between intervention and control groups at baseline showed that the intervention group scored significantly higher on the binge eating scale compared to controls, 9.1 (3.5) versus 7.2 (3.9), respectively, t(60) = 2.03, p < .05, and reported significantly lower levels of physical activity, 5.3 (4.2) versus 7.3 (3.7), respectively, t(60) = 2.04, p < .05. Other measures were well matched (see Table 3).
Workshop attendance
Of the 31 people randomised to the workshop condition,
Discussion
As far as we are aware the present study is the first attempt to adapt mindfulness-based techniques for a programme designed exclusively for weight loss. Despite the exploratory nature of the trial, the results are promising with intervention participants losing 1.35 kg more than controls at 6 months and showing a relative increase in physical activity of 2.81 sessions per week. When the data were re-analysed excluding those who reported ‘never’ using the workshop techniques at 6 months these
Acknowledgements
The research was funded by the Welsh Office of Research and Development (grant RFS 05-1-071). We thank Jeremy Gauntlett-Gilbert for advice on intervention development, and Nazanin Azimian and Fiona West for help with data collection.
References (49)
- et al.
Does emotional eating interfere with success in attempts at weight control?
Appetite
(1990) - et al.
Assessment of emotional, externality induced and restrained eating behaviour in nine to twelve-year-old obese and non-obese children
Behavior Research Therapy
(1997) Psychological aspects of weight maintenance and relapse in obesity
Journal of Psychosomatic Research
(2002)- et al.
A new cognitive approach to the treatment of obesity
Behaviour Research and Therapy
(2001) - et al.
Acceptance-based treatment for smoking cessation
Behavior Therapy
(2004) - et al.
The assessment of binge eating severity among obese persons
Addictive Behaviors
(1982) - et al.
Acceptance and commitment therapy: model processes and outcomes
Behaviour Research and Therapy
(2006) - et al.
DBT, FAP, and ACT: how empirically oriented are the new behaviour therapy technologies?
Behavior Therapy
(2004) - et al.
A preliminary trial of twelve-step facilitation and acceptance and commitment therapy with polysubstance-abusing methadone-maintained opiate addicts
Behavior Therapy
(2004) - et al.
Eating behaviour correlates of adult weight gain and obesity in healthy women aged 55–65 years
American Journal of Clinical Nutrition
(2002)
Food craving, dietary restraint and mood
Appetite
Maintenance and relapse after weight loss in women: behavioral aspects
American Journal of Clinical Nutrition
A randomised controlled trial of a behavioural intervention to reduce high-risk sexual behaviour among adolescents in STD clinics
Behavior Therapy
Screening for physical activity in family practice. Evaluation of two brief assessment tools
American Journal of Preventive Medicine
The three-factor eating questionnaire to measure dietary restraint, disinhibition and hunger
Journal of Psychosomatic Research
On the relationship between emotional and external eating behaviour
Addictive Behaviors
Eating style a validation study of the Dutch eating behavior questionnaire in normal subjects and women with eating disorders
Journal of Psychosomatic Research
Eating style and eating behaviour in adolescents
Appetite
The use of acceptance and commitment therapy to prevent the rehospitalization of psychotic patients: a randomised controlled trial
Journal of Consulting and Clinical Psychology
The moderator–mediator variable distinction in social psychological research: conceptual, strategic, and statistical considerations
Journal of Personality and Social Psychology
Mindfulness: a proposed operational definition
Clinical Psychology: Science and Practice
Mediators of change in emotion-focused and problem-focused worksite stress management interventions
Journal of Occupational Health Psychology
Cited by (242)
Cool or hot: How dietary restraint produces both positive and negative eating behaviors
2024, Food Quality and PreferenceEffects of mindfulness-based interventions on anthropometric outcomes: A systematic review and meta-analysis
2023, Obesity Research and Clinical PracticeEfficacy of ACT-based treatments for dysregulated eating behaviours: A systematic review and meta-analysis
2022, AppetiteCitation Excerpt :Two of these recruited US veterans self-reporting dysregulated eating (Afari et al., 2019; Cuneo et al., 2018) and two recruited post-bariatric surgery patients (Bradley et al., 2016; Weineland, Arvidsson, Kakoulidis, & Dahl, 2012). Six studies exclusively recruited female participants (Berbette, 2016; Boucher et al., 2016; Forman et al., 2009; Juarascio et al., 2017; Katterman, Goldstein, Butryn, Forman, & Lowe, 2014; Tapper et al., 2009). Only six studies recruited individuals independently of weight status, four of which recruited individuals experiencing either emotional eating (Berbette, 2016; Frayn, Khanyari, & Knauper, 2019) or binge eating (Juarascio et al., 2017, 2021).