Obesity and Discrimination in the Workplace: A Narrative Review and New Perspectives for Breaking Out of the Negative Spiral

1. Introduction

Global adult obesity has more than doubled since 1990, and in 2022, one in eight people worldwide were living with obesity [1]. Obesity is a multifactorial disease, most often due to environmental, psychosocial, and genetic factors, and results from an imbalance between energy intake (diet) and energy expenditure (physical activity) [1]. Obesity is associated with many health risks. Health risks include metabolic syndrome, diabetes, coronary heart disease, depression, high blood pressure, high cholesterol, sleep apnea and respiratory problems, stroke, gallbladder disease, osteoarthritis, and some cancers [2]. Increased health risks in obese people are associated with increased obesity-related medical costs [3]. One study showed that an increase in BMI from 30 to 35 increases the likelihood of medical claims by 25% to 37% [4]. Moreover, obesity is associated with reduced quality of life, increased mortality, and reduced workplace productivity [5], absenteeism [4,6,7], and increased work-related injuries and disabilities [7,8]. For example, obese employees miss 3.7 more days of work per year than normal-weight employees [9], and the impact is twice as high in obese people with diabetes [10]. Cross-sectional [11,12,13,14,15] and longitudinal studies [16] have also shown that obesity is associated with productivity and presenteeism. For example, the results of two studies conducted in Canada and Belgium showed that obesity was significantly associated with reduced productivity [12,13]. A US study concluded that the rate of presenteeism in obese workers was 12% higher than in workers of a healthy weight [15]. It is often argued that the lower productivity of obese people is due to their obesity impairing the performance of executive functions and limiting their ability to successfully accomplish tasks [17,18]. Industrial workers who engage in various physical movements, such as bending and extending their arms and legs, may experience difficulties with these movements due to obesity [18]. Obesity is also associated with the development of musculoskeletal disorders, osteoarthritis, rheumatoid arthritis, and carpal tunnel syndrome [19,20,21], and excess fat mass in obese people increases biomechanical and physiological stress during physically demanding activities [22]. Workers with these health conditions are more likely to experience physiological and respiratory strain during the performance of strenuous physical work, leading to reduced tolerance to effort [23,24] and reduced tolerance to sleep disorders [24,25,26,27,28].

Overweight and obese people are stigmatized and discriminated against in various social situations, including the workplace [3,29]. Obese employees are perceived as less disciplined and competent [30,31,32,33], and obese salespeople are perceived as less reliable, punctual, energetic, and polite [34]. As a result, obese people are reported to be less likely to be employed [35,36,37,38], earn lower salaries, and be promoted less frequently than their average weight counterparts [39,40,41,42,43]. According to some estimates, the wage penalty suffered by obese employees ranges from 0.6% to 12% of the wage of non-obese employees [44]. Possible reasons include the aversion and prejudice that employers or customers may have toward obese workers [45], as well as the importance placed on their reputation among external and internal stakeholders [46]. Previous research has shown that companies with obese frontline employees have lower customer ratings for brand equity, service quality, satisfaction, and purchase intentions than companies with average-weight frontline employees [47]. In addition, overweight and obese employees are also subject to derogatory comments and other disrespectful behavior from their superiors and coworkers [48]. Thus, obese people are at risk of illness and reduced productivity, and at the same time, they are subject to discrimination, and therefore need improvement for both economic and humanitarian reasons. However, given the various risks faced by obese people, there is a certain rationality for employers to discriminate against them, such as not hiring them. Previous research has pointed out that the economic discrimination suffered by obese people is often done not because of employers’ preferences, but for the compelling reason of wanting to avoid losses due to reduced productivity [42]. The complexity of the situation surrounding obesity has caused researchers to refrain from addressing the underlying mechanisms of obesity [49]. In this study, we summarize the main debates surrounding obesity in the workplace and confirm that obesity is often both the cause and the result of various behaviors, in other words, it is part of a “vicious cycle.” Based on this, we argue that to reach an optimal solution for society, consensus building and policy intervention at the local and national levels are necessary, rather than leaving the response to obese employees to the discretion of individual organizations.

2. Discrimination Increases Obesity Risk and Reduces Productivity

Discrimination against obese people is often justified because they are less productive. However, the causal relationship can also be reversed, that is, discrimination increases obesity risk and reduces productivity. According to one study, 20% of overweight and obese people report experiencing weight-related stigma [50]. This stigma is the condescension and condemnation of the social value of heavier individuals [51]. It is the fourth most common form of discrimination among adults, after discrimination based on age, sex, and race [52]. The experience of stigma leads individuals who identify themselves as overweight or obese to experience fear of being stigmatized based on their weight [53], which leads to social identity threat [54,55,56]. When humans experience social identity threat, it can have negative effects such as increased anxiety and increased physiological stress responses [57], which can negatively impact health [58]. Therefore, people experiencing identity threats adopt self-regulatory strategies such as suppressing negative emotions [57,59,60]. Self-regulatory strategies consume cognitive resources, which may lead to poorer task performance immediately afterward [61]. Ironically, increased stress and depletion of cognitive resources contribute to obesity. First, stress increases cravings for sweet and fatty foods, leading to increased food consumption and weight gain through the deposition of visceral fat [62,63,64]. Depletion of cognitive resources also leads to a loss of control over not eating tempting but unhealthy foods, which again leads to high food consumption and weight gain [65,66,67,68].

These suggest that experiencing weight stigma may lead overweight individuals to eat more, rather than less. The validity of this paradoxical mechanism has been confirmed in several experimental studies. In a study by Major et al. [69], participants who had experienced stguma consumed more high-calorie snacks when they read a news article about the stigma faced by overweight individuals in the job market. Similarly, in a study by Schvey et al. [70], overweight participants consumed more than three times as many calories as a control group after watching a video that portrayed negative stereotypes about obesity (e.g., lazy, clumsy, and noisy). Other studies have shown that experiencing weight-based stigma can lead to inappropriate eating behaviors [43,71], reduced physical activity [60,72], and reduced self-efficacy for exercise and diet management [59]. Furthermore, stereotyped people often internalize the stigma against them [73] and believe that they are less capable of meeting the demands of the job [74]. Thus, obese employees who experience weight-based stereotypes may underperform their job performance, which in turn fuels stereotypes about obese people, creating a vicious cycle [74]. These findings are surprising, given that stigma has been seen as a potentially powerful source of social control [75] and as a potential driver of weight loss [76,77,78], and thus has tended to lead to the prevalence of stigmatizing policies that highlight how frightening it is to be obese [79].

Stigma can still have positive effects. The study by Major et al. [69] was notable for the fact that participants who did not perceive themselves as overweight were exposed to messages blaming their weight, which increased their self-efficacy to control their eating [69]. One possible explanation for this finding is that the weight-blaming messages acted as a fear appeal to non-obese participants. That is, increasing the fear of weight stigma could increase motivation and ability to avoid being overweight [69]. Weight stigma may contribute to weight gain among people who already perceive themselves as overweight, while it may deter weight gain among those who do not.

3. Childhood Family Environment and Obesity

So, what is the “starting point” of this vicious cycle? Even if stigma drives obese people to further obesity and reduced productivity, discrimination against them would be unlikely if the individual avoided obesity in the first place. In that sense, obesity is a sign of poor self-control, and there may be a certain degree of rationality in discriminating against obese people by not hiring them. However, if we look at the environment in which they grew up, we realize that it is difficult to attribute their obesity to their own responsibility.

For example, previous studies have revealed that maternal employment is significantly associated with adolescent obesity [80,81,82]. Of these, a study by Andrie et al. found that in the normal weight group, most mothers were unemployed (i.e., full-time housewives), while in the overweight/obese group, most were public sector employees [80]. Furthermore, Anderson et al. observed that the longer a mother worked, the higher the risk of her child becoming overweight or obese [83]. The main pathways associated with weight gain include time allocated to household chores, including food preparation, and reduced maternal supervision of children’s food intake and physical activity [84,85,86]. Furthermore, evidence has confirmed that parental marital status plays an important role in the emergence of obesity in adolescents [82,86,87,88], and that a stable family environment is important for maintaining a normal weight [89]. One study showed that a significantly higher proportion (28%) of overweight and obese adolescents had divorced parents than normal-weight participants (15.3%) [80]. Children from single-parent families are less likely to eat at the table with their parents and are more likely to play or watch television during meals [90]. Furthermore, children from single-parent families reported consuming more total fat, saturated fat, and sweetened beverages, and watching more than two hours of television/video each day, compared with children from two-parent families [91]. In this context, psychological problems such as anxiety and depression, lack of physical activity, and poor school performance were associated with overweight/obesity in adolescents [81]. In addition, adolescents who are victims of bullying may suffer from poor mental health, including low self-esteem [92], depression, and anxiety [93], and the psychological trauma that results may precipitate the onset of obesity [94,95]. If these handicaps are carried over into adolescence, they are more likely to be disadvantaged in terms of employment and schooling. It has therefore been argued that obesity is likely to be transmitted cyclically from parent to child [96,97]. This argument is reinforced by demographic data showing that obesity rates vary by race/ethnicity, education, and economic level. The prevalence of obesity among U.S. adults is 37.7%, with higher rates among women than men (35.0% vs. 40.4%) and among blacks (48.4%) and Latinos (42.6%) than whites (36.4%) and Asian Americans (12.6%) [98]. Furthermore, obesity is unequal across education, income levels, and occupations. 32.8% of adults who did not complete high school were obese compared with 21.5% of adults who graduated from college/college. Approximately 34% of adults earning less than $15,000 per year are obese compared with 24.6% of adults earning more than $50,000 [99]. Furthermore, disparities may encourage the persistence of obesity across generations. 80% of children of obese parents are obese compared with less than 10% of children of normal weight parents [100]. Cross-country data from developed countries shows that the prevalence of obesity among adults and overweight teenagers correlates with the degree of economic inequality in a country [101]. Thus, obesity is largely produced and perpetuated by distortions and inequalities in social structures. This means that attributing obesity to individuals and eliminating them from employment and other areas is illogical, as it is as if we are affirming a distorted social structure.

4. Discussion

It is a great achievement that research into obesity and discrimination has led to the discovery of a vicious cycle. The fact that obesity is caused by various social and economic factors, including family structure in childhood, makes it unjustifiable to discriminate against obese workers simply because they are less productive. For the same reason that hiring sexual minorities and people with disabilities is recommended from the perspective of promoting diversity, organizations are also required to make efforts to incorporate obese people without discriminating against them. At the same time, the accumulation of evidence that obesity reduces productivity means that obesity should be improved rather than left alone. The fact that it is something that is accepted but also sought to be improved is a unique feature of obesity, and is what makes it difficult for people to deal with it. Therefore, there is a strong argument that obesity is a personal responsibility and that people should be discriminated against in employment. This is the weakness of the “vicious cycle” theory. Considering the pragmatism of breaking the vicious cycle somewhere, there is a certain rationality in the strategy of stigmatizing obese people. This kind of “logic of the strong” is very powerful. This is because in a society where such logic prevails, not only obese people but also those who employ obese people are likely to be negatively affected and suffer disadvantages [46,47]. Therefore, to fight this powerful logic, it is a mistake for researchers to make the “vicious cycle” theory their destination, and they need to deeply examine and correctly understand the effects of stigma. If stigma contributes to reducing the number of obese people as a result, we must admit that there is a certain rationality in continuing to use it as a weapon to break the vicious cycle. On the other hand, if stigma does not have such power, we need to reconsider our strategy.

Stigma may be effective in preventing non-obese people from becoming obese [69]. Therefore, instilling fear of becoming obese in people has a certain effect. However, there is little evidence that blaming obesity promotes weight loss [69]. Rather, it has been shown that stigma has the effect of trapping obese people in a vicious cycle of becoming more and more obese [69,70]. This shows that in societies with a small number of obese people, discrimination based on obesity has a certain degree of rationality, while in societies with many obese people, discrimination based on obesity is likely to no longer be rational. Therefore, the more local governments and companies launch anti-obesity campaigns and promote obesity as a villain that should be eradicated, the more it will educate people who are not obese, but it may become even more difficult for people who are already obese to break free from obesity.

Why have humans acquired such irrational traits? Previous research has yet to provide an answer to this question, so let’s make a bold deduction. The “thrifty gene hypothesis,” one of the evolutionary hypotheses addressing the question of why humans are prone to obesity, argues that individuals who were able to store energy as fat during times when food was abundant may have had an advantage during times when food availability was unstable, and may have been able to survive famines [102]. This means that tending to be prone to obesity means that individuals have a higher risk response ability during times of unstable food supply, and as a result, a higher survival ability. By applying this thrifty gene hypothesis, it is possible to infer the reason for obesity caused by stigma. In other words, if we assume that individuals who sense the threat of exclusion from the group due to stigma overeat to store fat and energy in anticipation of a future in which they may no longer receive support from others, we can explain why they overeat because of their stress response and are prone to obesity. Furthermore, obese people who are discriminated against by others will increase their obesity by overeating, which will result in lower productivity and more discrimination, making the tendency irreversible and enhancing their perfection as a bad example. The more an individual who falls into the negative spiral of stigma and obesity is discriminated against by those around them, the more it strengthens the fear of becoming obese for non-obese people who witness it, which in turn encourages them to suppress overeating.

As mentioned above, there is already ample evidence that obese people are less productive [11,12,13,14,15,16], and this is probably true as an average trend when individual differences are controlled. However, previous studies have also shown that it cannot be denied that part of this low productivity is due to stress and autosuggestion caused by stigma [61,73,74]. Therefore, it is not clear to what extent obese people are less productive after controlling for various factors, because previous studies have used diverse research subjects and methods, and some reviews have argued that the evidence on the relationship between obesity and presenteeism, unemployment, and early retirement is inconsistent [7]. Nevertheless, there seems to be little doubt that body shape is an obstacle in jobs that require physical use such as bending and stretching the arms and legs, and there is a wealth of accumulated evidence [17,18,22]. In the past, people who were obese enough to cause inconvenience in moving their limbs were almost nonexistent in hunting-based eras, but they began to appear with people settling down and the beginning of agriculture [99]. In agriculture, even today in an age of mechanization, there is evidence that obese people are less productive [104], so obesity may have been an even greater hindrance to productivity in times when labor was reliant on human labor. Therefore, to prevent other members from becoming obese, stigma may have been used to publicize how becoming obese would damage one’s reputation within the organization and prevent others from cooperating with them. Although it is difficult to find evidence as to when discrimination against obese people began, there are records of obesity being considered a medical abnormality in ancient Greece and ancient Egypt [105], and obesity being seen as a cause of diabetes and heart disease in India in the 6th century BC and physical labor being recommended as a way to alleviate these conditions [106], so it is possible that it was widely known from ancient times that becoming obese could diminish one’s value as a worker. At that time, the stronger the stigma against obesity, the greater the effect. If the punishment was simple and could be undone later, the effect of setting an example would be reduced. Although strict rules may reduce the chances of rehabilitation for obese people, if the benefits of maintaining group discipline outweigh the disadvantages, it is rather rational as a group behavior, even if such disadvantages are taken into consideration. The fact that humans have evolved to maintain their survival ability by prioritizing group logic over the individual has been argued in evolutionary biology by terms such as “indirect reciprocity” in humans, who place importance not only on bilateral but also on multilateral reputations [107].

However, in today’s developed countries, where sedentary work is the norm, the rationality of such stigma seems to be declining. However, given that obese people are more susceptible to illness and that it has a negative impact on organizations in the long run, employment discrimination is somewhat rational at the organizational level. However, if a certain number of people are unable to break free from the vicious cycle of obesity due to stigma, this leads to increased medical expenses and reduced productivity, so it is irrational when evaluated at a larger level such as a municipality or country. Therefore, since attempts to reduce the obese population are difficult to promote at the organizational level such as a company, it is necessary for municipal and national levels to take the initiative, build a consensus among residents, set guidelines, and properly guide small-scale organizations such as companies. First, measures such as prohibiting employment discrimination based on body shape should be taken so that people who are already obese can break free from the vicious cycle. After ensuring the safety of obese people in this way, measures should be taken to reduce obesity in a way that does not stimulate stigma.

Already, with the backing of local and national governments, some companies have not only not discriminated against in employment for obesity, but have also demonstrated a willingness to intervene to reduce obesity [7] and have implemented health interventions [108]. For example, mandatory exercise in the workplace can lead to improved employee health and productivity, which is a win-win for employees and employers. However, there is a large heterogeneity in the types of workplace-based interventions to prevent or treat obesity, so sound conclusions cannot yet be drawn about their overall effectiveness and best practice recommendations for their implementation [7]. Moreover, mandatory exercise can place employees in a vulnerable position, as employers may interfere with some of their fundamental rights, namely bodily autonomy and privacy [108]. Moreover, the increased emphasis on exercise and physical fitness in the workplace can lead to discriminatory practices, as employers may exclude or sanction those who cannot or do not want to exercise for various reasons [108]. As such, such health interventions may ultimately encourage further obesity by making obese people feel more strongly about being obese. The body of research covered in this review suggests that efforts to reduce obesity must be approached with great caution.

In that sense, interventions that focus on the mental health of obese people may contribute to their weight loss while avoiding stigma. Employees with higher levels of true self-awareness, knowledge about different aspects of the self and confidence in that knowledge [109], understand their true selves and invest in learning more deeply [110], have higher self-insight (i.e., a clear understanding of different aspects of the self), self-acceptance (i.e., a positive attitude toward the self), and self-esteem (i.e., confidence in their own value), and tend to have lower anxiety, cognitive and emotional tension, and health disorders [110]. Employees who understand themselves better are less likely to submit to undesirable social and situational pressures in the work environment and tend not to react as strongly to the demands of others and workplace stressors [110]. Thus, true self-awareness may help employees cope with the stressor of weight-based stereotype threat [29,74,109,110,111]. Since workplaces do not always have a correct understanding of obesity, it is recommended that obese people who are unlucky enough to be employed in discriminatory workplaces have a strong mentality so that they do not fall into a vicious cycle caused by stigma. It is meaningful for the government to support them so that they can have such a self.

Future research should focus not only on ways to reduce obesity, but also on ways to break out of the vicious cycle of obesity without stimulating stigma. Also, considering that obesity and the factors surrounding it are cyclically related as both cause and effect, more research should be conducted using longitudinal methods rather than cross-sectional methods. Therefore, it is necessary to clarify how people who were once obese were able to overcome obesity through randomized controlled trials, cohort studies, case-control studies, etc.

5. Conclusions

This review paper reviews previous research on obesity and discrimination in the workplace and presents a perspective that supports the rationality of supporting obese people to break out of the vicious cycle, not only for the obese people themselves but also for society. Obesity is known to not only lead to various diseases but also to reduce the performance of workers. However, the vicious cycle of reduced performance and worsening working conditions due to obesity is difficult to break out of once it has been caught in, as it is reinforced by stigma and leads to employment discrimination. Therefore, it may be possible to save these people by forming a consensus on the social acceptance of obese people through the initiative of local governments and the country.