The Interplay of Gender, Mood, and Stress Hormones in the Association between Emotional Eating and Dietary Behavior

Human and animal studies indicate that stress may affect eating behavior in various ways, under different circumstances. Generally, intense emotions trigger inhibited food intake through fight-or-flight responses, which result in glucose release into the blood stream, thus suppressing the feelings of hunger (1). Conversely, impaired cognitive eating control, emotion-congruent modulation of eating, and eating to regulate emotions have been suggested mechanisms underlying abnormal eating behavior observed in groups of individuals (2). In such instances, stress enhances intake of palatable and ‘‘nutrient poor’’ foods, high in sugars and saturated fat content (3–5), thereby reducing intakes of fruits and vegetables and overall dietary quality (6,7). Alternatively denoted as ‘‘stress-related eating,’’ ‘‘eating comfort foods,’’ and ‘‘emotional eating,’’ this behavior is a direct consequence of negative mood states, such as sadness, loneliness, and concern (5,8–10). In the long run, such eating behavior contributes substantially to weight gain at the individual level (11), thereby increasing the burden of obesity at the population level (12–14). Generally speaking, abnormal eating behaviors leading to increased risk of obesity include a combination of emotional eating (i.e., eating as a result of negative mood states), uncontrolled eating (i.e., not being able to control the amount of food consumed as a result of external triggers), and low cognitive restraint (i.e., inability to restrict food intake in order to control body weight) (10). In this issue of The Journal of Nutrition, Camilleri et al. (15) examined the relation between emotional eating and consumption of energy-dense snacks by using data on French adults collected from a large cross-sectional survey. The analysis involvedmultiple linear and logistic regression models in which gender and depressive symptoms were included as potential effect modifiers of the main association. The key finding was that among depressed women, emotional eating was associated with greater consumption of energy-dense snacks. This synergism between emotional eating and depressive status was not found among men. Several instruments to assess emotional eating were used in the current study and in the past literature that either incorporated a limited range of emotions or mood states or inquired further about binge eating episodes (16–21). The measure of emotional eating used in the study by Camilleri et al. (15) is a subscale of the French version of the Three-Factor Eating Questionnaire (TFEQ-R21) (20); the 2 other subscales were ‘‘uncontrolled eating’’ and ‘‘cognitive restraint’’ subscales. Similar to the Emotional Eating Scale (21), this subscale tackles the direct response to a wide range of emotions in terms of urge to eat. Those affective states include anger/frustration, anxiety, and depression. A study in generally overweight men and women indicated that the Emotional Eating Scale (21) has a 4-factor structure (Anger, Anxiety, Depression, and Somatic), accounting for 60% of the total variance, with ;40% of this total variance being explained by the Depression factor (22). Consequently, depression is a major contributor to emotional eating. It ensues that the association between depressive symptoms and intake of non–health-promoting foods is potentially mediated by emotional eating. In fact, using structural equations modeling techniques and data from Finnish men (n = 2312) and women (n = 2674) aged 25–74 y, a recent study found that both emotional eating and physical activity self-efficacy are important mediators between depressive symptoms and adiposity (5). Another study from the same group of researchers in 25to 64-y-old Finnish men (n = 1679) and women (n = 2035) from the FINRISK 2007 Study (Dietary, Lifestyle and Genetic Determinants of Obesity and Metabolic Syndrome substudy) came to the conclusion that emotional eating was also a mediating factor between depressive symptoms and increased intake of sweet foods but not the of reduced intake of fruits and vegetables (23). Recent methodologic advancements allow to test mediation while relaxing the exact additivity of effects assumption between exposure (e.g., emotional eating) andmediator (e.g., depression) variables (24,25), thus disentangling those 2 potential effects. Moreover, in the study by Camilleri et al. (15), the observed synergism between depression and emotional eating in relation to consumption of high-energy-dense snacks was restricted to women. Given the large sample size in both genders, inadequate statistical power to detect the association among men is an unlikely explanation. Moreover, another large cross-sectional study also observed this relation to be stronger among women (11). An alternative explanation is that men respond to stress by decreased appetite (26,27), whereas women are more susceptible to engage in emotional eating behavior as a function of their menstrual cycle and hormonal phase (28) as well as a possible gene-depression interaction present only in women (29). Over many years, emotions and mood have been shown to influence food choice. This observation was primarily explained via sensory, physiologic, and psychological pathways (30). For instance, eating a meal may reduce arousal and irritability and increase calmness and positive affect, whereas a small meal portion size may have opposing effects on mood (30). Sweetness and fatty structure can also improve mood by activating brain opioidergic, dopaminergic, and benzodiazepine/g-amino butyric acid neurotransmission (30). In fact, dopamine neurotransmission 1 Author disclosures: M. A. Beydoun, no conflicts of interest. 2 Supported by the Intramural Research Program of the National Institute on Aging, NIH. * To whom correspondence should be addressed. E-mail: baydounm@mail.nih. gov.