Stress and comfort eating

People eat to make themselves feel better during periods of sadness, stress, unhappiness, boredom or loneliness. Comfort eating is not a problem in moderation, but under today’s increasingly stressful environment, individuals are regularly using eating to cope. This is having a negative effect on our health.

According to the National Health Survey carried out in Australia during 2004,¹ roughly 5 million people were suffering from moderate to very high psychological distress. The types of stress suffered are quite varied. Links have been found between emotional eating and work stress (including high workloads), social pressures, depression and low self-esteem. This is a problem that is contributing to the current obesity epidemic and the associated negative consequences. In 2004, it was estimated that nearly 2.5 million Australians were considered obese.¹ Aside from the increased risk of poor health and disability resulting from obesity, this epidemic is costing the Australian health service millions of dollars. It is therefore important that we identify the causes of comfort eating in order to treat this eating disorder effectively.

So why are people resorting to comfort eating? Recent research is showing evidence that comfort eating individuals are reacting to both psychological and chemical responses to stress.² Evidence is showing that comfort foods tend to be chosen based on sweetness with fatty tastes. These foods can be seen as part of a treat or reward system, boosting an individual’s mood. In addition, stressful situations can be characterised by anxiety and depression, and are related to high tension and lower energy. As such, stressed individuals are associated with compensating for this effect with greater energy and fat intake in their diets, and less healthy foods. Some food companies are using this trend to market products such as sports drinks, caffeine drinks and snack bars to provide both physical and ’emotional’ energy.³ Studies comparing sugar-sweetened and artificially sweetened soft drinks found that both forms of the beverage were associated with high BMI and emotional eating.⁴ This suggests that it is the taste rather than the sugar content that is necessary for a comfort eater, and emphasises the idea that these foods are used as treats.

Eating when hungry is both gratifying and rewarding. The act of eating activates neural substrates in the brain. Evidence shows that the neural substrates from the dopamine, opioid, and benzodiazepine/GABA neurotransmitter systems are linked to a ‘reward’ response in the brain.¹ It is thought that these systems give the motivation to want and enjoy food. These are also involved in adaptive responses to stress and discomfort. In animals and human babies, sweet and fatty foods alleviate crying and other behavioural signs of discomfort. This effect depends on the sweet taste and can be blocked by opioid antagonists. Studies have found that pain tolerance in adults and children can be extended by sweet taste, such as that from sucrose solution, suggesting an opioid-mediated relief of stress.¹

Some differences have been found based on gender and age.⁴ Emotional eating has been positively correlated with BMI in women but not in men. Some findings support the idea that obese people have a neurochemical predisposition that may cause overeating. This is supported by findings that obese women compared to non-obese women will put a greater effort into obtaining energy-dense snack foods and that young children of obese parents show greater ‘enjoyment of food’ and a higher preference to energy-dense snack foods.¹ As many studies are based on self-reporting measures of eating styles, it may be that societal pressures cause women to assess their styles of eating more critically than men. This is important to note as it may inflate gender differences found in such studies.

Research is finding that the ‘sensitivity to reward’ was lower in obese than in overweight individuals.¹ This suggests that as comfort eating progresses, it can become a chronic condition, and an individual will need increasing amounts of food to obtain the same stress-relief reward. This can almost be seen as a self-perpetuating cycle synonymous to drug addiction. As such, it is imperative that effective treatments be devised.

Discussion and education with a physician are important to help establish concepts of normal eating, dieting and exercise patterns. A physician/dietitian can also help develop a diet with appropriate nutrition with instructions of sensible ways to limit fat and sugar intake as well as encouraging proper exercise. In more extreme cases, cognitive therapy can be used to correct dysfunctional thinking patterns and assumptions about food. In addition, interpersonal therapy can be used to identify and improve the underlying problems that resulted in the development of this eating disorder.

References:

1. National Health Survey: Summary of Results 2004-05. Australian Bureau of Statistics, Feb 2005.
2. Gibson EL. Emotional influences on food choice: Sensory, physiological and psychological pathways. Physiology and Behavior. 2006; 89: 53-61.
3. Reid M. Food marketing in the 21st century: building the consumer-marketer connection. [online] Accessed October 2007. Available from url: www.natsoc.org.au/html/papers/reid.pdf .
4. Elfhag K, Tynelius P, Rasmussen F. Sugar-sweetened and artificially sweetened soft drinks in association to restrained, external and emotional eating. Physiology and Behavior. 2007; 91: 191-5.
5. Wansink B, Cheney MM, Chan N. Exploring comfort food preferences across age and gender. Physiology and Behavior. 2003; 79: 739-47.