Name: Pamela A. Dyson
Affiliation: Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Oxford, UK.
In the UK, weight reduction is recommended as the primary therapy for the 90% of people with type 2 diabetes who are overweight or obese [1], and Carole’s story indicates that this was the case for her once diabetes had been diagnosed. A simplistic view of obesity states that it results from an imbalance between energy intake and energy output, and that weight loss can be achieved simply by reversing this imbalance. In reality, the etiology of obesity is far more complex and includes genetic influences, physiological and biochemical factors and environmental and behavioral effects [2, 3].
One aspect of obesity treatment that is frequently overlooked is that of eating in response to cues other than hunger. This is often referred to as emotional eating and includes binge eating, external eating and eating in response to food cravings [4]. Carole eloquently describes how emotional eating became her coping mechanism during times of stress.
Binge eating disorder (BED) is now a formal diagnosis and is characterized by eating large amounts of food in a discrete time period while experiencing a lack of control over eating [5]. Prevalence rates of BED are estimated to range from 1 to 4% of the general population, and approximately 40–50% of individuals with BED are obese [6]. External eating is characterized by eating in response to the sight, smell or taste of food rather than to internal hunger cues [7], and food cravings are defined as obsessive thoughts and the compulsive consumption of specific foods [8]. Although little is known about the prevalence of these different manifestations of emotional eating, there is evidence that disordered eating generally may affect around 40% of people with type 2 diabetes [9] and that they are more common among obese individuals than among those of normal weight [10].
Emotional eating is associated with eating as a means of dealing with negative emotions, in an attempt to regulate these emotions [11]. For many people, a typical reaction to stress is to seek out and consume energy-dense foods, often referred to as “comfort foods” as they evoke a psychologically comfortable and pleasurable state [12]. It is intuitive that high levels of stress would be associated with obesity, but the evidence for this is inconsistent, although a recent meta-analysis reported that stress was positively associated with increasing adiposity [13]. The prevalence of emotional eating is unknown, but a recent study in the USA reported that 38% of adults engaged in unhealthy eating behaviors in response to stress [14], and 57% of overweight adults self-report frequent emotional eating [15].
In the case study described above, Carole reports a significant degree of emotional eating and describes comfort eating during her pregnancy and when diagnosed with postnatal depression. She recognizes that during times of stress, for example, when solely responsible for her children’s upbringing when her husband was working abroad and after her mother became ill, her coping strategy was to turn to food. She also describes how she could successfully lose weight for short periods of time, but as soon as she experienced any considerable amount of stress, her comfort eating would return.
In common with many people’s experience, Carole’s story illustrates that emotional eating is a significant factor both for promoting obesity and preventing long-term weight loss. Weight management programs which fail to address these specific eating behaviors are unlikely to have successful outcomes, especially over the longer term.
Useful Interventions
Behavioral modification is the key to managing emotional eating. A variety of effective strategies have been identified, including CBT, interpersonal therapy (IPT) and mindfulness, although some of these are intense, individualized and costly interventions that may be challenging for widespread implementation [16].
CBT is designed to change the way people think (cognition) and what they do in response to those thoughts (behavior). It can be delivered by an accredited therapist, although self-help using books and internet-based and computerized programs are available. CBT is widely used in the treatment of eating disorders, and components of this therapy are often included in weight management programs. A recent meta-analysis reported that CBT reduced emotional eating and increased cognitive restraint, resulting in significantly greater weight reduction than in comparator groups, although there was no difference in depressive symptoms [17].
IPT is an intense, structured therapy working on established interpersonal issues and primarily focusing on the way relationships affect mental health, thoughts and behavior. IPT is an evidence-based treatment for eating disorders in which binge eating is a feature, but there is little evidence of its efficacy for the management of other eating disorders [18]. Its intense, individual application means that it is rarely included in general weight management programs.
Mindfulness has been defined as the learned ability to be open, accepting and present in the moment, and developing mindfulness allows for adaptive responses to habitual thoughts, emotions and behaviors. In terms of weight management, mindful eating encourages a non-judgmental awareness of the physical and emotional sensations of food and supports self-regulation. Over the past few years, there has been increased interest in mindfulness-based interventions (MBI) for weight management and emerging evidence for their inclusion as a component of weight management programs [19,20,21].
Components of Weight Management Programs
In the UK, the recommended first-line strategy for weight loss is structured education programs that incorporate dietary advice, physical activity and behavioral management [22]. For people with diabetes, it is also crucial that aspects of diabetes management are addressed. These components are all essential for success, and the case of Carole illustrates well how she was unable to maintain long-term weight loss when attempting weight loss with programs that did not include all of these constituent strategies. Upon referral to the Oxfordshire Diabetes Weightwise program, Carole was offered a multi-component package which included advice on diet, physical activity, diabetes management and behavioral strategies. Weightwise is a weight management program which is available on referral to people with type 1 and type 2 diabetes who are treated with insulin or sulfonylureas and who are therefore at risk of hypoglycemia. Each course lasts 6 months and consists of 2-h sessions held every 2 weeks for the first 3 months, followed by monthly follow-up. The program is offered at a variety of community venues across the Oxfordshire region, and groups typically consist of 6–15 participants. Each program is designed to meet the cultural, cognitive and literary needs of the local population in order to address equality and diversity [23].
Dietary Advice
There is no consensus on the ideal diet for people with diabetes who wish to lose weight, but there is general agreement that adherence predicts outcomes [24]. For that reason, it is recommended that people adopt a diet that suits their particular style of eating and personal food preferences [1]. Carole was offered a variety of dietary strategies and was provided with support in finding an approach that best suited her.
Physical Activity
There is no evidence to suggest that physical activity in isolation is effective for weight loss in people with type 2 diabetes [25], but it does play a role in weight maintenance and is an effective strategy for improving glycemic control and general well-being and for reducing cardiovascular risk [26]. Carole has demonstrated the benefit of increasing her physical activity by walking and joining a gym.
Behavioral Strategies
Behavioral strategies are a key component of the Weightwise program. Emotional eating is addressed using CBT and some aspects of mindfulness, and all participants are encouraged to self-monitor using food and mood diaries to identify those situations in which they use emotional eating to manage stress. There is evidence that self-monitoring can support weight loss if framed as a positive tool [27], and in Carole’s case, she was supported in using a diary to identify food cravings and external eating. She also used a Smartphone application to monitor her levels of activity and general food intake, and this strategy was recommended to all group participants using a choice of either electronic or paper diaries.
Various strategies to manage emotional eating are introduced over the course of the program, including relapse prevention, coping planning, problem-solving and managing food cravings. These techniques are known as implementation intentions [28], more commonly called ‘if–then’ strategies, and are designed to address specific stressful situations by encouraging links between a critical situation (‘if’) with an appropriate response (‘then’). In addition to coping strategies, the program includes fostering self-acceptance and emphasizes the role of thoughts in driving feelings and behavior. Unhelpful thoughts and thinking errors, such as catastrophizing and mind-reading, are explored and challenged. Providing a non-judgmental atmosphere in which all participants feel safe and supported and able to explore their thoughts and feelings is fundamental to the program.
Diabetes Management
There is evidence that it is more challenging for those with type 2 diabetes to lose weight than it is for those without diabetes, and that this difficulty is exacerbated by insulin treatment, which is itself associated with weight gain [29]. One aim of weight loss is to improve (or maintain) glycemic control while avoiding hypoglycemia and achieving this balance requires both blood glucose monitoring and active insulin dose titration. In the Weightwise program, participants are encouraged to monitor blood glucose levels between two to four times daily, and insulin titration takes place under medical supervision. An essential part of the program is carbohydrate awareness and management, with the aim to minimize the risk of hypoglycemia. Carol describes how the combination of reduced dietary intake, increased physical activity, weight loss and blood glucose monitoring allowed her to safely reduce her insulin from 74 to 6 units Levemir daily.
In summary, Carole has shown that successful, long-term weight loss is possible in people with type 2 diabetes treated by insulin, but that a multi-component program which includes behavioral strategies was the key to her success.