What causes obesity?

Obesity is usually caused by regularly consuming more calories than we burn up. However, what is leading people to consume more calories and burn up fewer of those calories now than in previous generations?

One answer is that we’re now living in an ‘obesogenic environment’ – with much greater access to food , especially fast food, which is now available 24/7, often without needing to leave home. In addition, more people are now employed in sedentary jobs, which means people are moving less (and therefore burning fewer calories) throughout their day. As a result, less than 2 in 3 adults are taking the recommended amount of physical activity each week in the UK.

However, despite all this, only some people become obese. To fully understand why some people are obese (and others aren’t) the focus may need to shift from what makes someone obese towards why some people are obese. The psychology behind emotional eating may provide some answers here. It potentially helps explain why some people struggle with their weight, despite not necessarily living obviously different lives to their normal-weight counterparts. 

What does the evidence suggest?

Studies have consistently found that emotional eating (eating in response to negative emotions) contributes to an individual’s weight more than external cues, such as the availability and price of food. Emotional eating has been overwhelmingly associated with over-eating and is a particular concern in people who struggle to effectively regulate their emotions. Emotional eating can occur from both positive emotions, such as joy, and negative emotions, such as depression. Both types of emotions are significant here. 

However, binge-eating has been specifically associated with negative emotions, most notably depression. When experiencing negative emotions, emotional eaters are more likely to consume foods with a higher fat, sugar and calorie content as opposed to healthier options. This is clearly relevant when it comes to obesity. It has also been suggested that prolonged high fat food consumption can lead to a negative emotional state, which in turn may lead to more comfort eating, creating a vicious cycle. 

In intervention studies that examine weight loss and its relationship with emotional eating, those who reported less emotional eating at the beginning of the study were more likely to achieve a 7% weight loss within six months of the intervention, compared to those who reported more frequent emotional eating at the beginning of the study.

In many studies a difference has been observed between levels of emotional eating in adults compared to children  The prevalence of emotional eating in children is very low, suggesting that children tend to naturally lose their appetite in response to negative emotions and stress. This likely means that emotional eating emerges in adolescence, which correlates with the idea that many adolescents overeat during times of emotional distress, for example due to exams. Stress has been found to be the main cause of emotional eating in adolescents.

There are also differences observed when it comes to mental health. The most prominent mental health condition that impacts emotional eating is depression. Often emotional eating appears to act as the mediator between depression and obesity. Advising people who are obese because of depression and emotional eating to pursue a calorie restricted diet is therefore likely to be less effective than addressing the cause of the emotional eating, by improving emotion regulation.

Options available to those struggling with emotional eating

Acceptance and Commitment Therapy (ACT)

ACT is a recent development in the field of Cognitive Behavioural Therapy (CBT) that works over several weeks to enable individuals to choose their responses to internal emotions . ACT helps individuals understand their personal values and tries to empower them to choose actions that align with these values. ACT aims not to eliminate these “dysfunctional cognitions” but instead equip people with the tools necessary to enjoy life on their terms, without feeling controlled by their emotions and subsequent emotional eating. The current evidence suggest that ACT is effective in treating eating-related cognitive dysfunctions, but as a relatively new style of therapy more research is needed.

Dialectical Behaviour Therapy (DBT)

DBT is a type of CBT that can help with eating disorders  It combines the acceptance element of ACT, where an individual is encouraged to accept themselves “as they are” while also motivating them to change habits that can lead to undesirable health outcomes, which in the case of emotional eating is obesity. DBT requires structured coaching with a professional who can help individuals build the skills required to overcome emotional eating habits. The results of DBT in treating eating disorders are promising but have not yet been compared enough to other methods to say whether it is more effective than other forms of CBT.

Recommendations

1. Individuals who struggle with emotional eating to the point that it impacts their day-to-day life should seek help from a trained professional who can work with them to build new skills and practices to stop emotional eating causing detrimental health outcomes.

2. The eating disorder charity Beat is another useful resource. It has helplines which can offer support and information about eating disorders: Helpline: 0808 801 0677; Studentline: 0808 801 0811; and Youthline: 0808 801 0711 

Beat offer a private and non-confrontational space to discuss thoughts and feelings around eating disorders. It can also signpost individuals to places where they can access therapy or other forms of help, on their own terms, allowing them to make their own informed decisions.

3. The UK government is slowly beginning to take action to reduce the obesogenic environment in the UK, through the actions proposed in its Obesity Plans, and pressure will continue on the government from health professionals and charities, including those who are members of the Obesity Health Alliance. However, to complement this action, there needs to be continuing action to improve mental health, not least in the current pandemic, to seek to tackle the issue of emotional eating at source.

Molly Faries February 2021