Do Individuals With Overweight and Obesity Have Reduced Affective and Cognitive Empathy? A Systematic Review and Meta-Analysis

The average body mass index (BMI) has been increasing worldwide since 1975, reflecting an increase in the prevalence of overweight and obesity among children, adolescents, and adults; in several countries, these conditions affect more than 80% of the population [1]. Overweight and obesity are complex and multifactorial conditions characterized by elevated body fat and progressive weight gain, which may be exacerbated throughout life [2]. In particular, obesity has been recognized as a chronic disease by the World Health Organization (WHO). Among the many diagnostic criteria that can be used to measure excess body weight in adults, BMI, which is calculated as the ratio of weight to height squared (kg/m²), remains the most commonly used. Accordingly, a BMI ranging from 25 to 29.9 kg/m² indicates overweight or preobesity, and a BMI of at least 30 kg/m² indicates obesity [3]. Overweight and obesity are associated with a greater risk of health complications, such as cardiovascular disease, type 2 diabetes, chronic respiratory disease, nonalcoholic steatohepatitis, and various forms of cancer [4], all of which can lead to a shorter life expectancy [5, 6].

Based on an etiological approach and maintenance models, it is generally suggested that overweight and obesity should be treated with a biopsychosocial approach [2, 7, 8]. This perspective accounts for that the etiology of these conditions is multifactorial and may be influenced by genetic factors [9-11], endocrine and neurological factors [12-14], medical factors [15, 16], and psychological factors [17-19].

With respect to psychosocial factors, individuals with obesity are more likely to experience a range of intrapersonal and interpersonal difficulties. For example, they exhibit higher levels of anxiety and depression [20, 21] and have greater difficulties with emotion regulation [22]. In particular, individuals with obesity exhibit higher levels of emotional eating than the general population [23]. There is also a high prevalence of eating disorders among adults with obesity [24, 25]. Most notably, binge-eating disorder (BED) appears to be strongly associated with obesity. In the general population, the lifetime prevalence of BED is 5.49%, 3.08%, and 1.36% in females with obesity, overweight, and normal weight, respectively; these prevalence rates are slightly lower among males [26]. Among candidates for prebariatric surgery who present severe obesity, the prevalence rates of BED have been shown to range from 4.2% to 44.5% [27]. Conversely, 36.2%–87.8% of BED patients will develop obesity in their lifetime [28]. These findings support the close interplay between obesity and BED.

With respect to interpersonal functioning, individuals with obesity report more social isolation, more perceived weight stigma, and fewer attempts to socialize than normal-weight individuals do [29, 30]. Individuals with obesity also report a greater propensity to avoid social situations because they expect rejection [31]. Empathy, which may be related to these social challenges, is a central component of interpersonal functioning, as it promotes better interpersonal emotional regulation [32] and more prosocial behaviors [33, 34].

Empathy is a multidimensional concept that has been extensively investigated for approximately 40 years. Since then, researchers have attempted to define empathy and explore its multidimensionality. For example, a review indexed 47 definitions of empathy [35], suggesting that “empathy” is an umbrella term. Similarly, a review documented the diversity of definitions and supported the necessity of going beyond the concept of empathy and focusing on the exact low-level construct that is examined [36]. Even if it is necessary to acknowledge that “there is no way to ascertain which definition is correct” (p. 64) [37], the term empathy generally includes “cognitive” and “affective” dimensions. For example, Baron-Cohen and Wheelwright [38] defined empathy as “the drive or ability to attribute mental states to another person/animal, and entails an appropriate response in the observer to the other person's mental state” (p. 168). This definition illustrates that the cognitive dimension of empathy generally refers to the ability to understand another person's mental state (e.g., emotions and beliefs), whereas the affective dimension generally refers to the experience of an appropriate affective response to another person's misfortune (e.g., compassion and sympathy). At a methodological level, depending on whether one is considering the affective or cognitive dimension, measuring empathy mainly includes self-reports (e.g., subjective affective experience and self-rated measure of the propensity to take another's perspective) and behavioral performance (e.g., accurate identification of another's mental states).

In a transdiagnostic approach, empathy, and more specifically difficulties in understanding another person's mental state, has been suggested to constitute a mechanism that may be common to separate disorders and that may maintain them [39]. Accordingly, poor abilities to attribute another's mental states are highly prevalent across 31 clinical conditions within psychiatric (e.g., anorexia and bulimia nervosa), neurological, and developmental disorders [40]. In parallel, cognitive and affective empathy develop early, and some studies have shown that both constitute protective factors against the development of mental disorders [41]. For example, social cognitive abilities based on a false belief task at ages 5 and 7 predict fewer internalizing (emotional) and externalizing (behavioral) problems at ages 14 and 17 [42]. These results clearly indicate that empathy, especially cognitive empathy, may constitute a clinical marker that needs to be investigated among individuals with obesity.

In relation to weight and obesity, research has focused mainly on empathic skills among children and adolescents. The literature on empathic skills among adults with overweight and obesity remains limited, and the results have been inconsistent. Therefore, the potential link between weight and empathy needs to be clarified. This systematic review and meta-analysis aimed to examine the associations of empathy with overweight and obesity in adult populations. Previous studies have shown that weight is negatively correlated with empathic skills in children and adolescents [43]. Correlation models, which are limited in terms of drawing causal inferences about obesity, have suggested an association between empathy and BMI among adults. For example, among adults with a BMI ranging from 19.03 kg/m² (normal weight) to 35.38 kg/m² (Grade II obesity), BMI is associated with a greater likelihood of having empathy deficits [44]. When examining separate weight categories, a systematic review based on samples of children, adolescents, and adults suggested that obesity is linked to difficulties in empathy, particularly in terms of emotional recognition [45]. Regarding cognitive empathy in particular, a narrative review of children, adolescents, and adults revealed inconsistent results regarding the ability of individuals with overweight and obesity to recognize other people's emotions [46]. Unfortunately, these findings were not stratified based on age, thus preventing any separate conclusions from being drawn for each age category. Although very informative, Tonelli and de Siqueira Rotenberg's [45] systematic review did not include a meta-analysis; thus, there was a lack of statistical support for their results, and their review cannot be used to draw stronger conclusions about the association between empathy and obesity in adults.

When examining empathy as a risk factor for obesity, we hypothesized that empathic difficulties increase the likelihood of presenting psychosocial difficulties and of using maladaptive strategies to cope with them. Previous studies have shown that impaired recognition of another's emotions is associated with interpersonal problems such as social inhibition, coldness, or lack of assertiveness [47, 48]. Consequently, when socializing, empathy difficulties might increase the risk of experiencing distress because of high discomfort or ostracism, which could lead individuals to rely on maladaptive coping strategies such as emotional eating. In support of this hypothesis, Hayman et al. [49] revealed that social ostracism increases subsequent food consumption in healthy participants. In the long term, as emotional eating increases the risk of gaining weight [50], one may hypothesize that empathy deficits may account for obesity issues through social distress and maladaptive emotion regulation strategies. On the other hand, when empathy is considered a maintenance factor, the literature indicates that people suffering from overweight or obesity are particularly exposed to weight stigmatization and tend to internalize this stigmatization and anticipate stigma [51, 52]. These factors are known to increase the risk of social isolation [53], which can deteriorate the ability to accurately recognize another's mental state (e.g., threat bias) [54, 55]. In this work, we hypothesize that these two paths might interact, creating a vicious cycle between empathy difficulties, distress, and eating disorders (such as BED) and the development and maintenance of obesity. In both cases, individuals with obesity are expected to have lower levels of empathy.

Therefore, investigating this question among adults is particularly relevant for several reasons: (1) It provides insight into the understanding of empathy as a maintenance factor; (2) fewer studies have been conducted in adults than in younger individuals; (3) these studies are associated with inconsistent findings; and (4) they go beyond Tonelli and de Siqueira Rotenberg's [45] review, which was limited to a narrative review, mixing young and adult populations, and focused solely on the dimension of cognitive empathy. The added value of the present study is thus to focus on adults only, to examine both cognitive and affective empathy and to base our conclusions on a meta-analysis. Finally, the present study also aims to focus at moderators such as age, sex, weight range, or eating disorders.

To our knowledge, no previous systematic review or meta-analysis has specifically examined the associations of empathy with overweight and obesity in adults. The objective of this meta-analysis is thus to examine the current literature on empathy in adults with overweight and obesity. We hypothesize that empathy is associated with overweight and obesity. Specifically, we expect to observe more cognitive and affective empathy difficulties in individuals with overweight and obesity than in normal-weight individuals. The secondary objectives of this study are to determine the effects of several variables, including weight range (overweight vs. obesity) and the presence or absence of eating disorders (e.g., BED), on the relationship between weight and empathy.

The objective of this study was to identify whether individuals with overweight or obesity would present empathy difficulties, with the hypothesis that they would present lower levels of cognitive and affective empathy than normal-weight controls do. On the basis of 10 studies and 11 datasets, this meta-analysis revealed that when data from individuals with overweight and obesity are pooled, individuals with overweight and obesity present lower empathy than normal-weight individuals do. However, subgroup analyses revealed no significant difference between people with overweight and people with obesity. Interestingly, the effect size for cognitive empathy is larger than that for affective empathy, suggesting that although these conclusions must be treated with caution, individuals with overweight or obesity present lower cognitive empathy with preserved affective empathy. Similarly, subgroup analyses indicate that individuals with overweight or obesity have impaired empathy when studies are based on performances measures compared to self-report questionnaires.

These results are consistent with previous results among children and adolescents. For instance, Turan et al. [82] reported lower performance on the Reading the Mind in the Eyes task among adolescents with obesity than among controls with normal weight. Similarly, other studies have shown impaired emotional recognition skills in children with obesity [43, 83, 84] and in children with overweight or obesity [85] compared with normal-weight children.

The empathy deficits associated with obesity are consistent with findings from the narrative review of Tonelli and de Siqueira Rotengerg [45], who reported that individuals with obesity or overweight had worse performance on cognitive empathy tasks. As their results were not stratified by age, our study is the first to provide empirical evidence regarding this association in adults with obesity or overweight. Nevertheless, as only four studies (and five datasets) included in the present meta-analysis tested individuals with overweight, one cannot confidently draw conclusions on the absence of a difference between overweight and obesity, and further studies are needed to determine whether empathy deficits might be particularly noticeable and typical of the obesity stage.

Various hypotheses can be proposed to explain the empathy difficulties associated with obesity. Although this assumption is speculative, this association might be related to stigmatization and social isolation. Indeed, evidence suggests that obesity is associated with the frequent occurrence of discriminatory experiences related to weight stigma [86, 87], social exclusion, or ostracism [88]. Although this requires further in-depth studies, stigmatization may increase the risk of social isolation or loneliness [53], which is known to be associated with low (self-reported) empathy or even a deteriorated ability to accurately recognize others' mental states (e.g., threat bias) [54, 55], possibly because of reduced opportunities to develop empathy abilities.

In terms of moderators, even if the effect of BED could not be tested, one can hypothesize that BED influences the association between obesity and empathy [76]. Indeed, whereas authors have shown no significant difference in empathy abilities between weight groups (normal vs. obesity), there was a positive association between the presence of BED and low empathy (but see Turan et al. [82] and Aloi et al. [89] for opposite results in children). The literature suggests that people diagnosed with an eating disorder (not limited to BED) are likely to have impaired empathic skills [90, 91]. Because BED is a frequent comorbidity of obesity, we can therefore assume that difficulties in empathy observed in people with obesity mainly concern those who also suffer from BED. This hypothesis requires further investigation, as there is currently no consensus about the impact of a BED on the recognition of other people's emotions among patients with obesity. It can be assumed that this effect is driven by variability in the recruitment of participants (e.g., seeking weight management vs. in the general population) and the criteria and instruments used to determine the presence of BED (e.g., Binge Eating Scale and clinical interview).

In addition, a better understanding of the role of empathy deficits in interpersonal difficulties is necessary. Previous studies have highlighted various social difficulties associated with obesity, such as low assertiveness and excessive accommodation [92]. Associations between low abilities to recognize others' emotional expressions and interpersonal difficulties have already been shown in different clinical populations, such as anorexia nervosa [93] or alcohol use disorders [48], thus supporting the importance of exploring the relationship between empathy difficulties and interpersonal difficulties in individuals with obesity. As presented in the introduction, empathy deficits may increase the risk of social distress by deteriorating social functioning and increasing the risk of relying on maladaptive strategies to cope with these impaired social interactions.

The association between obesity and empathy could thus be bidirectional and constitute a vicious cycle. Specifically, empathy deficits might lead to greater social distress, resulting in higher risk behaviors, such as avoiding healthcare centers and adopting inappropriate coping mechanisms (e.g., controlling weight [51] and disturbances in eating behavior [94]). These maladaptive behaviors might then increase weight gain, causing weight gain to constitute a key factor in the development and maintenance of obesity. Future studies are necessary to examine this research perspective.

The secondary objective of this study was to determine whether certain factors could play a moderating role in the association between weight and empathy. Our results revealed that neither age, sex, nor the risk of bias were significant moderators. Moreover, as previously mentioned, we could not test the effect of BED. However, individuals with overweight or obesity demonstrate worse empathic abilities when using they were based on performance measures compared to self-report questionnaires, possibly suggesting a tendency to overestimate one's own skills in questionnaires in this group. This finding needs to be treated with caution, as it may also be linked to the psychometric qualities of the instruments used. On the other hand, further studies should use robust methodologies to test empathy performances (e.g., avoid tasks that are influenced by the individual's vocabulary [95]).

In conclusion, this meta-analysis revealed for the first time that adults with overweight or obesity have empathy difficulties, particularly cognitive empathy difficulties. This emphasizes the need for further research to use a multidimensional approach to understand which empathy dimensions are particularly impaired and the necessity of conducting studies to evaluate affective empathy beyond self-report questionnaires. Future research should also determine the role of BED and the possible contribution of empathy difficulties to interpersonal difficulties and to the onset/maintenance of obesity.

CM and DG designed the research study. CD and DG supported the conceptualization of the study. DG coordinated the review. CM performed the literature searches. CM, CD, and DG participated in abstract and title screening. CM and CD conducted the full-text screening and data extraction. PG performed all analyses and interpreted the data. CM, DG, and PG wrote the paper. All the authors critically reviewed the drafts and edited the manuscript. All the authors have read and approved the final manuscript.

The authors declare no conflicts of interest.