Binge eating in a Slovenian population-based sample of adults

Many constructs related to eating have been proposed to explain obesity, such as binge eating and emotional eating, both of which emphasise loss of control over food intake. Because food intake and eating behaviours are the result of numerous complex regulatory mechanisms involving both homeostatic and hedonic/non-homeostatic processes, obesity may manifest as eating in the absence of energy or metabolic deficits (1). A typical aspect of non-homeostatic eating (i.e. eating outside the physiological sensation of hunger) is binge eating, which is classified as disordered eating behaviour because it describes a type of inappropriate behaviour pattern and habit. It is characterised by eating more than normal in a given period of time and feeling a loss of control while eating (2). Because is characterised by episodes of overeating, it is a form of compulsive overeating (3). Binge eating is a major public health problem (4), in and of itself and because of the negative psychological and physical health complications associated with it (5), such as increased risk of mental disorders and obesity.

Studies report very high prevalence rates of binge eating in young adults, especially those whose weight status is classified as overweight/obese. In a recent study, 48.6% of young adults with overweight/obesity reported higher rates of binge eating than their normal-weight peers (29.3 vs. 15.8% in women, 15.4 vs. 7.5% in men) (6). A meta-analysis has estimated the prevalence of binge eating among adolescents with overweight/obesity to be 31.2%, and exploratory analyses have suggested that prevalence increases among adolescents who receive weight management treatment (7).

In adults, binge eating has also been associated with overweight/obesity, both cross-sectionally (8) and longitudinally (9). In a sample of 2,134 adolescents, binge eating reported at baseline predicted the onset of obesity at ten-year follow-up, demonstrating the importance of understanding the relationship between binge eating and weight across an individual’s lifespan (10). Disordered eating behaviours are more common in women than in men (11). A previous study of binge eating in a sample of Slovenian adults showed that women had higher levels of binge eating symptomatology and emotional eating than men (12), and according to some data, 62% of middle-aged participants in Slovenia have inappropriate eating habits (13). A study of a sample of adolescents showed that the number of individuals with binge-eating problems was relatively high among secondary school students (14).

In addition, binge eating is a key behaviour in eating disorders, such as binge eating disorder (BED), bulimia nervosa and the binge-purge type of anorexia nervosa (2, 15). BED is the most common eating disorder, occurring in approximately 10–15% of people in the community (16, 17) and is associated with food addiction, as they share a common symptom – binge eating (18–20). Importantly, BED is associated with adverse medical and psychosocial outcomes and is often associated with multiple somatic and psychiatric conditions, including obesity, metabolic syndrome, substance use disorders and mood disorders (21–23).

Despite the strong association with binge eating, some factors have received little attention in the general population and beyond. These include emotional eating, anxiety, and demographic factors such as gender and body weight, which are thought to be important contributors to the association with binge eating (24–26). The concept of emotional eating refers to the tendency to eat in response to emotional triggers, such as negative/positive emotions or stress (27–28), and may be associated with overeating in response to food-related stimuli such as the sight and smell of attractive foods (29). Overall, emotional distress (e.g. depression, anxiety) may be associated with binge eating and could predispose individuals to develop and/or maintain inappropriate eating behaviours.

The prevalence of obesity and eating disorders is increasing worldwide (30). It is estimated that 51% of the population will be obese by 2030 (31), with prevalence expected to peak between 2026 and 2054. The US and the UK are projected to reach the highest levels first, followed by other European countries (32). Because obesity is one of the greatest health challenges of the 21st century in many countries (33), it is worthwhile examining individual differences in eating behaviours. These are likely, at least in part, to explain individual differences in obesity (34). Considering that both conditions are related to many other health problems, the main objective of the study was to examine binge eating in a sample of adults from the general population and to explore the factors that might be related to food intake.

The main objective of this study was to investigate the association between binge-eating behaviour, anxiety and emotional eating in a population-based sample of adults in Slovenia, and to assess differences by gender, BMI, and age. In this study, self-reported binge eating was 29.9%, with 20.1% of participants reporting moderate binge eating and 9.8% reporting severe binge eating. The self-reported frequency is higher than some reports, e.g. 9.9% (44) and 5% (45), but lower than the highest frequency of binge eating recorded to date, i.e. 44% (46). The differences in reporting of binge eating might be related to the demographic diversity of the sample studied. The sample in this study was dominated by women (90.9%), and the majority of participants were between 20 and 39 years old. In addition, the proportion of overweight and obese individuals was high (41.8%), which may explain the high number of reported binge-eating behaviours in our sample.

Indeed, the results of this study showed a significant association between binge eating and higher BMI.

Furthermore, they show a statistically significant positive association between anxiety and binge eating in a large sample of adults. This finding is consistent with previous studies that have shown a positive association between anxiety and binge-eating symptoms (47, 48) in the general population (26). Our results also show that anxiety accounted for 18.3% of the variation in this problematic eating behaviour. Similarly, previous research has shown that anxiety has a significant impact on the severity of binge eating (47, 49), and that loss of control is an important feature of both anxiety and binge eating (24, 25, 49). The mechanisms by which anxiety promotes binge eating are not fully understood (47). One explanation is that binge eating is a calming behaviour for anxious people, comparable to nail biting, smoking, alcohol use or drug use, or that eating is a means of coping with these anxieties (25). In fact, anxiety is a component of negative affect that has been shown to play an important role in the development and maintenance of eating disorders such as binge eating (30), and is the most common precursor to disordered eating (49). In general, there is still a need for a better understanding of the role of anxiety, as anxiety symptoms are generally high in individuals who engage in binge eating.

Moreover, participants with higher BMI who reported more anxiety were more prone to binge eating and had a more pronounced tendency to overeat. The results of our study of the general population sample show that women had statistically significant higher rates of binge eating, anxiety and emotional eating than men. The lower rates of binge eating among men in our study can be explained by the findings that risk factors for binge eating differ between genders (26, 30). Moreover, participants with higher BMI had statistically significant higher levels of emotional eating and binge eating. Given that obesity has become a major health problem in Slovenia (50) and worldwide (18), and that, according to some data, 62% of middle-aged participants in Slovenia have inappropriate eating habits (13), the binge eating revealed in our sample is cause for concern. Moreover, younger participants reported significantly higher anxiety scores than older participants. Interestingly, a recent study (51) on binge drinking found that this risky behaviour is very common among young adults. Because the term ‘binge’ refers not only to eating but also to extreme and uncontrolled activities (e.g. drinking, eating, fasting), this overall finding warns us that risky behaviours among the young population are a serious health problem.

Importantly, BMI is one variable that has been linked to binge eating. It has been proposed as a relevant causal factor in disordered eating in conjunction with emotional eating (12), although BMI has often been treated as an outcome (52). A potential complication with BMI is that binge eaters who engage in frequent intense exercise are, due to their high calorific expenditure, not necessarily overweight (53).

Since we conducted the study after the third wave of Covid-19 and the subsequent lockdown in Slovenia, the higher levels of anxiety and disordered eating could also be related to that particular time and to the lockdown. Indeed, during the early phase of the spread of Covid-19, researchers (54) demonstrated a relationship between population anxiety levels, psychological distress and prevention efforts. Although some studies (55) observed a decrease in health-related habits, such as alcohol consumption, after the initial lockdown, it has been suggested that an increase in these problematic habits may follow in the future. The data to date shows that the higher percentage of meals consumed at home, such as pizza and pasta (56), affected individual behaviours. Many people reported having eaten more during the lockdown and having had more unhealthy eating habits, such as the consumption of comfort foods (57). Crucially, some of them attributed these changes to higher anxiety (57, 58). This study has some limitations. The first limitation is that the results cannot be statistically extrapolated to the population, and that statistical inferences (e.g. hypothesis tests and p-values) cannot be drawn based on a sample of the population, with the error term based on sampling error. Second, the proportion of women and men was not equal, making it difficult to generalise about gender differences. Although this study showed that women have higher levels of binge eating than men, future studies should replicate this finding with a larger sample of men to increase the reliability of the group means. Moreover, data collection was based on self-reporting, which is a subjective method, and most questionnaire responses were given by young people. Similarly, other authors (59) have reported that the younger population are more likely to complete the questionnaire when it is posted online. In addition, self-reported height and weight were used to calculate BMI. Several studies indicate that self-reported weight and height should be used with caution, as middle-aged men and women are more likely to have biases; in particular, weight tends to be underestimated and height overestimated. BMI is not an appropriate indicator of diet, as higher BMI may be due to other factors (e.g. increased muscle mass, pregnancy, postpartum), as well as mental illness and treatment with medications that increase appetite and decrease energy expenditure.

As far as we know, this is the first study in Slovenia with a large sample of adult women and men with different BMI in the field of disordered eating research. The results of this study may be a starting point for the planning of appropriate interventions to identify at-risk individuals prone to negative emotionality and binge-eating symptoms at an early stage, as this may affect the individual’s subsequent mental and physical health. As mentioned previously (60), strategies to improve the overall health of the population rely on an adequate diagnosis of disease-causing factors so that educational interventions and targeted campaigns can be adapted with the aim of changing inappropriate eating habits, as well as accessible nutrition counselling provided as needed by qualified dietitians at primary health centres (59). In addition, the study findings provide evidence for other areas of work, e.g. by refining both cognitive-behavioural approaches, which have been shown to be a successful way of addressing BE symptoms (26) and developing more comprehensive obesity prevention and treatment programmes. For example, in order to prevent the use of food as a coping mechanism, the incorporation of emotion recognition and understanding, as well as coping strategies, may be more effective than focusing on just one. The research on binge eating by Barnhradt et al. (61) suggests that learning mindfulness can help people use more appropriate ways to cope with stress. Some (62) studies of binge eating in the general population have even suggested the promotion of a Mediterranean diet in the general population may play a key role in preventing BE episodes and the resulting potential weight gain, but conclude that further research is needed for this.

This study contributes to a relevant line of research in the field of disordered eating behaviours, particularly binge eating, and helps us to better understand this widespread problem in today’s society. It provides data on the relationship between binge eating and other comorbid variables, and shows that dysfunctional eating habits, such as binge eating, are associated with negative emotions such as anxiety, BMI, gender and age. Female participants and those with overweight or obesity were significantly more likely to report binge eating and emotional eating, and younger participants and females were significantly more likely to report anxiety. As binge eating is a risk factor for adverse health outcomes, the goal is not only to identify vulnerable populations for targeted interventions (e.g. gender, age, weight status), but also to identify risk factors that can be modified for prevention purposes. Health professionals should therefore closely monitor not only the current weight status of adults, but also their coping strategies, as binge-eating behaviour can be understood as a coping strategy in response to emotions. In an anxious state (with a lower or absent ability to regulate emotions), failure to regulate eating may occur, leading to unhealthy eating habits and increasing the likelihood of binge eating. Future studies should emphasise the above relationship and include some additional individual factors that may underlie high levels of binge eating and fat intake, such as the drive for thinness, body dissatisfaction, some behavioural patterns (impulsivity, loss of control), and eating styles/habits. All of these could help advance the field of eating behaviours that distinguish anxiety-induced eating in obesity and binge eating. This study paves the way for future investigations of the causal structure of associations between dysfunctional eating, gender and anxiety in all age groups in population-based Slovenian samples.