Those higher on neuroticism have been found to have higher BMI in a number of studies, and they suffer from diet-related health problems such as metabolic syndrome.
The explanation for this can be found in emotional eating, which has been linked to neuroticism. Emotional eating has its roots in psychosomatic theory — that is, people eat in response to negative emotions such as anxiety, in order to reduce these feelings and instead induce feelings of comfort and safety.
So, because neurotic people are more likely to feel negative emotions, they feel a stronger urge to comfort-eat. No wonder that people high in neuroticism consume more sugar and fats, eat less fruit, keep eating after they are full, binge eat and find it hard to avoid food flavored with fat (e.g. butter, cream).
Interestingly, Schaefer, Knuth & Rumpel (2011) report that theirs is the only fMRI study to have found neuroticism to be positively correlated with activity in the brain’s reward circuits. The stimuli used in the research were chocolate bars; the authors suggest that these are more rewarding for neurotic people since they use them as comfort foods.
However, neuroticism has also been associated with unhealthy eating on the other end of the spectrum. Studies have found high levels of the trait among those classified as underweight and those with eating disorders such as anorexia. The likely explanation is that neurotic people have lower self-esteem and feel greater pressure to refrain from eating. Indeed, several studies have correlated neuroticism with restrained eating.
What to Do?
So how can we use this information to shed a few pounds and fit into our bikinis — or mankinis? Although personality traits are largely stable over a lifetime, there are some short-term fixes. For example, introducing some conscientiousness by eating in a tidier room has been found to make people 47 percent more likely to choose an apple, over some chocolate, for a snack.
Beyond the role of personality, Brian Wansink’s Mindless Eating identifies a number of fascinating nudges which can help us eat less. For example, we eat less food off of red plates, we eat less food from smaller containers, and we eat less food when there is less variety to it (e.g. fewer flavors).
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