BMI Report Cards and its Failure in the Prevention of Childhood Obesity—Celina Chan

In recent years, obesity has become a growing problem among all members of the United States population. In particular, obesity rates have more than doubled among children 6 to 11 years old and more than tripled among those 12 to 19 years old since the late 1970s (1). Due to these alarming numbers, some state governments felt an urgency to combat this problem. Arkansas passed Act 1220 of 2003 to create the Child Health Advisory Committee to address childhood obesity and develop nutritional and physical activity standards (2). Among the tasks set out by the Act was a mandate requiring schools to include an annual body mass index (BMI) percentile in each child’s health report to parents. Although the intention of including a BMI percentile in a child’s health report was to alert parents of whether or not their children were at risk of developing obesity, it actually had negative consequences. The use of BMI percentiles in child health reports is an illustration of a flawed public health intervention due to the inaccuracy of BMI, the psychological and social consequences on children, and the failure to address factors that affect obesity.

Due to a large cash payment made to the state of Arkansas from a tobacco lawsuit settlement, the BMI test, along with other measures to target childhood obesity, came into existence. Health officials in Arkansas viewed it as just another screening test (3). The actual BMI report card that was sent out to parents contained the BMI given as a range on a bar graph and then a pointer that told parents which category their child fell into: “normal”, “at risk”, or “overweight” range. After Arkansas implemented this program, a few other states followed its example, including Delaware, South Carolina and Tennessee, and started issuing mandated BMI report cards (4). Legislators in other states have proposed them as well.

BMI, a poor measure of body composition in children

Although the BMI report cards aim to educate children and their parents about children’s risk of developing obesity, relying solely on BMI is not an accurate measure for risk of developing obesity. BMI, body mass index, is a number calculated from a child’s height and weight. BMI does not measure body fat directly and it is age-specific and sex-specific (5). Even though researchers, drug companies, and public health officials have relied on BMI for many years, BMI is not entirely accurate. Some people who are not at risk of being obese are incorrectly categorized as either “overweight” or “obese”. This is especially true for athletes whose bodies are mainly composed of muscle. Because muscle is denser than fat, many people who are physically fit are mistakenly classified in the “overweight” category (6). However, these people are actually less likely to die from an obesity-related illness than people who are categorized in the “healthy weight” category because people in the “healthy weight” category have more excess fat than those who are physically fit and wrongly categorized. If BMI is an inaccurate measure for adults, then it is even more inaccurate for children whose bodies are still growing. The percentage of body fat in children can change substantially when they are still growing. Thus, a clear relationship between BMI and development of obesity cannot be established.

In a study published in The International Journal of Obesity, researchers examined the relationship between BMI and levels of fat mass and fat-free mass among healthy 5 to 18 year olds. They used dual energy x-ray absorptiometry to measure fat and fat-free mass among 1196 subjects. Then they standardized these measures for height and calculated the fat mass index (FMI) and fat-free mass index (FFMI). Researchers found that the accuracy of BMI as a measure of adiposity varied greatly according to the degree of fatness (7). They found that relation of BMI to fat mass was strikingly nonlinear and substantial differences in fat mass were only seen in BMI levels that were above the 85th percentile. They concluded that although BMI-for-age is a good indicator of excess fat mass, BMI differences among thinner children can be largely due to fat-free mass. This study affirms that BMI should be used with caution since it does not always produce accurate results. A high BMI amongst children does not necessarily mean that they are overweight.

The negative consequences of the BMI report card

The intention of the BMI report card was to bring a child’s BMI to the attention of a parent. What public health officials failed to realize that both parents’ actions and children’s actions are affected when their BMI is brought to their attention. In an article featured in The New York Times, a six-year-old girl barely touched her dinner after learning that her body mass index was in the 80th percentile. She did not know what “percentile” meant or that children who score in the 5th through 85th percentiles are considered normal, but she was convinced that her teachers were chastising her for overeating (4). As illustrated through this article, children are confused as to what the BMI report cards tell them. Not only is it something that they don’t fully understand at a young age, but it also affects them negatively in a number of ways.

Receiving a BMI percentile in the form of a report card makes children feel stigmatized and could result in eating disorders. Erving Goffman, a noted sociologist, defined stigma as a gap between “virtual social identity” and “actual social identity”. “Virtual social identity” is defined as the character that people assume someone to be and the expectations bestowed upon this person. “Actual social identity” is the attributes and character that an individual actually possesses. When someone possesses an attribute that is different from others and that is negatively desirable, this person is thought to be “tainted” and this attribute is thought of as a stigma; there is a perceived gap between “virtual social identity” and “actual social identity” (8). Another sociologist, Gerhard Falk, wrote that all societies will stigmatize certain behaviors and conditions because doing so results in group solidarity by delineating “outsiders” from “insiders” (9). From the writings of these two sociologists, stigma is defined as something undesirable that sets a person apart from the rest of the population. There are people who are stigmatized and there are people who stigmatize others. A negative feeling is associated with stigma since it is viewed as something undesirable in a certain social context.

Relating the concept of stigma to obesity, a study published in The International Association for the Study of Obesity included explanations for the development of weight stigma. Understanding the importance of weight stigma is important in documenting the social and psychological consequences of obesity. The stigma of obesity is very strong. In regards to weight stigma, harassment and rejection from peers at school and negative teacher attitudes are all reactions to obesity. Even at a young age, negative attitudes are apparent. The report cites a study that documented weight prejudice in 3 to 5 year old children who judged an overweight child to be meaner and an undesirable playmate compared to a normal weight child (10). Later in the report, the authors explain the attribution theory, which suggests that people search for information that determines the causes of uncertain outcomes. When stigmatized people such as those with obesity are approached, people search for a cause and in turn form their reactions to this obese person. Therefore, stigmas are representations of society’s negative perceptions about certain groups (10).

Based on the work of the mentioned sociologists regarding stigma and the attribution theory, it is not hard to see how being overweight or obese is linked with a negative attitude. If children receive BMI report cards that categorize them as being “at risk” or “overweight,” they will attach this label to themselves. A self-fulfilling prophecy will result in these children because they feel that there is nothing that they can do to fix being overweight. In addition, these children are afraid that their peers will possess negative attitudes towards them if they find out that they are at risk of being overweight or overweight. Eating disorders could develop in children, such as the 6 year old girl mentioned in the New York Times article who no longer wanted to eat. These children will become self-conscious about their appearance and this problem will be further heightened due to attitudes from peers.

BMI reports don’t target the real cause of the problem

Schools that issue BMI report cards take the first step in raising awareness about potential risk for obesity in children. However, providing information is not enough for parents and children if there is no accompanying education on what BMI percentiles signify or future steps to take. Although much research has been done between BMI and other risk factors, not enough research has been undertaken to examine the psychological effects of BMI. In addition, simply handing a child a BMI report card does target the root of the obesity problem. Other factors that affect obesity in children must be taken into consideration. Measuring BMI is an individual level risk factor, but the problem of childhood obesity should be evaluated at the group level.

Food marketing has played an essential role in childhood obesity. A study conducted by the Institute of Medicine (IOM) states that food marketing intentionally targets children who are too young to distinguish what they see in advertising from the truth and that advertising induces them to eat high-calorie, low-nutrient “junk” foods. The IOM’s first conclusion is that the diets of American children are “in need of improvement”. At least 30% of the calories in the average child’s diet are from sweets, soft drinks, salty snacks, and fast food (1). Thus, it is not hard to see why many children’s diets are high in calories. Food companies market their products toward children because they know that American children spend nearly $30 billion of their own money on junk food, and companies design products to tap into this market. Marketing strategies include predominantly television advertisements but now include toys, games, songs, movies, celebrity endorsements, and the Internet (1). All of these techniques aim to teach children to recognize food brands and then pester their parents to buy them. Some campaigns even try to convince children that they know what they are supposed to eat and not their parents (1). These marketers explicitly try to convince children that they have control over their choices.

Marketing strategies for these food companies are clever in that they try to convince children that they have control when children know that they have little control or little say in the household. Thus, food marketing is one of the multiple factors that affect obesity in children and the effects of food marketing must be taken into consideration when trying to reduce obesity in children. If obesity is going to be reduced, public health officials should consider reducing the amount of food marketing targeted towards individuals or implement new marketing strategies that promote healthy food choices.

Another factor that needs to be taken into consideration is the social network that people belong to. According to the social network theory, the behavior of people in a social network influences behavior. A study published in the New England Journal of Medicine assessed the spread of obesity in a large social network. The authors of the study wanted to determine whether obesity might be spread from person to person, which could contribute to the increasing rates of obesity. They found that between mutual friends, a person’s risk of obesity increased by 171% if his or her friend became obese. Among friends of the same sex, a man had a 100% increase in the chance of becoming obese if his male friend became obese, whereas the female-to-female spread of obesity was not significant. The results suggest that the spread of obesity is less of a behavioral imitation and more of a person’s general perception of the social norms regarding the acceptability of obesity (11). Thus, the spread of obesity within social networks appears to be a factor in the obesity epidemic. If people’s actions are influenced by friends and family members within their social networks, then a BMI report card alone cannot target the obesity epidemic. A BMI report card does not take group level factors into consideration, such as group behaviors and attitudes towards weight gain within a social network.

Conclusion

Efforts of some states to issue BMI report cards to school-age children have proved ineffective in combating childhood obesity. In general, BMI is an inaccurate predictor in the risk of obesity in children. In addition, issuing BMI report cards has negative effects on children, especially in the way they perceive themselves and what they think others perceive of them if they are at risk of being overweight or are overweight. Finally, BMI report cards do not take group level factors into consideration and ignore multiple factors that contribute to the obesity epidemic. Overall, BMI report cards do not help in reducing obesity in children. The psychosocial effects of the BMI report cards need to be evaluated and other steps should be taken to target childhood obesity.

Integrating Social Theories to Create An Effective Intervention

Obesity has been referred to as a preventable cause of death and disability in the United States. However, obesity prevention has not gained nearly as much attention from public health professionals and from policy experts as tobacco cessation. Both smoking and obesity are highly prevalent. If obesity is not prevented during adolescence, problems can arise later in life. The distribution of report cards with body mass index (BMI) scores to children in certain areas of the country has proven to be an ineffective intervention. In order to target obesity, a multifaceted approach should be taken and not just a one-step approach that targets individual behavior. A combination of self-assessment, public programs, and a mass media campaign should be undertaken.

Obesity should be prevented in adolescence in order to avoid potential medical costs associated with obesity later in life. The costs of obesity could be potentially appalling, arising from rising medical expenses and diminished worker productivity that is caused by physical and psychological disabilities (12). One of the most effective ways to improve health and prevent obesity-related illnesses is to change personal behavior. Behavioral causes account for nearly 40% of all deaths in the United States (13). Thus, by changing behavior, the public’s health could be improved. Using this principle, an intervention to target obesity should be based on the principle of behavior change. In addition, a more effective intervention than BMI report cards can be undertaken by improving upon the flaws of this intervention.

An alternative to solely using BMI

Although BMI has been widely used as a method to measure the risk of obesity, BMI scores can be misleading. In the multinational INTERHEART study conducted by Yusuf S et al, investigators compared the predictive value of BMI with other markers of obesity among people who have or have not had myocardial infarctions (MI). When adjusting for eight MI risk factors, the excess risk associated with a high BMI was completely eliminated (14). Instead, the investigators found that high waist-to-hip ratio had the strongest association with MI risk and high BMI had the weakest association (14). The investigators also found that larger waist size, which reflects the amount of abdominal fat, was harmful, while larger hip size, which may indicate the amount of lower body muscle, was protective. This suggests that waist-to-hip ratio is better than BMI for predicting the risk of developing myocardial infarctions.

The waist-to-hip ratio is fairly simple to calculate and all that is needed is a measuring tape. After taking measurements of the waist circumference and hip circumference, divide the circumference of the waist by the circumference of the hips. For women, the waist-to-hip ratio should be no more than 0.8, and for men it should no more than 0.95 (15). Ratios higher than these cut-off points denote a higher risk for developing obesity. Measuring waist-to-hip ratios are relatively easy and can be conducted within one’s home instead of a school setting. Instead of receiving BMI report cards, parents should be sent educational material on ways of assessing risk of obesity, such as measuring waist-to-hip ratios. This will eliminate the need to measure BMI scores in school settings and parents can elect to measure waist-to-hip ratios if they feel that it is necessary. If educational materials that contain information on waist-to-hip ratios are distributed to parents, they will be able to decipher if a child’s waist-to-hip ratio is a cause for concern. However, it should be noted that since children are still growing, a waist-to-hip ratio could be somewhat inaccurate. Children could lose their belly fat before they reach adulthood and thus the waist-to-hip ratio would not be accurate. On the other hand, since studies have shown that waist-to-hip ratios are more effective than BMI scores, it is worth taking the time to measure waist-to-hip ratios in children.

Changing Social Norms

In order to eliminate stigma attached to labeling a child as obese, BMI report cards should be eliminated, especially if children do not fully understand the meaning of BMI. Instead, an approach that has more positive implications should be undertaken. For children, an appropriate approach would be to implement an intervention through schools since children spend a majority of their time in a school setting. Also, children are very concerned about how their peers perceive them and by changing norms in schools, negative attitudes or stigmas can be avoided.

According to the social expectations theory, people act as a mass and follow social norms. If people are viewed as a herd of cattle for instance, then changing the social norms will shepherd people towards that model of behavior. The theory states that individual behavior is largely a result of conformity to the expectations of others (16). Experiences are influenced by social networks as well as mass media and observation of others as to what is acceptable. By taking this theory into account, the behavior of large numbers of people can be changed and not just a few people.

State governments can propose a ban on the sale of soft drinks and certain types of junk food, such as candy and chocolate, in all public schools. In Massachusetts, a smoking ban was put into effect in all restaurants, bars, and nightclubs in the state. As a result of the drastic decrease in toxins that are produced from cigarette smoke, the air quality of these businesses improved significantly (17). In addition, a shift in social behavior occurred as smoking prohibition in restaurants and bars became the norm. When people walk into these businesses, they can expect that smoking is prohibited. Similarly, a ban on the sale of soft drinks and/or junk foods in public schools could have similar positive consequences.

If a ban to this effect is implemented, it will take some time to adjust to the change, but positive consequences could result. First, not drinking soda in school or not eating junk food would become the norm. If people are exposed to these items less and don’t expect to attain these items in school, they will desire them less. In addition, if the majority of students are replacing soft drinks with water or other types of juices with low sugar content, other students will start to follow this behavior. The objective is to change the majority of the students’ behavior so that they do not expect to purchase soft drinks or junk food in school. If children begin bringing soda or junk food from home to school, it is unavoidable since it is a matter of personal preference. However, hopefully by implementing a ban, the school creates an environment where not drinking soda is the norm. Also, by changing norms and expectations, an individual is not singled out and stigmatized since the individual can choose whether or not to participate in this behavior. There is no label that is attached to an individual who does not conform.

Evaluating Obesity at the Group Level

Addressing obesity at the individual level will not help to alleviate a public health problem that affects the whole nation. One way to reach out to a large audience is to implement policies that will either change advertisements from the food industry or regulate food advertising. There has been data that indicates that children see between 27 to 48 food advertisements for each advertisement that promotes fitness or nutrition (18). Other statistics show that American children are exposed to approximately 40,000 food advertisements per year, 72 percent of which are for candy, cereal, and fast food (19). In addition, reviews by the American Psychological Association and the Institute of Medicine (IOM), show that advertisements shape product preferences and eating habits (20). Thus, food advertising has profound effects on children and adolescents. If their behavior is being shaped by these advertisements, then in order to change their behavior, the advertisements must be changed.

Social marketing techniques, which were first introduced by Kotler and Zaltman, treat behavior change as a product that is being marketed (21). Potential customers, the target population, think of the behavior change in the same manner as they do about other product choices. The goal is to have people voluntarily adopt the behavior because they believe that it is in their interest to do so. In order to influence people to adopt the behavior, the product must be presented as being attractive in terms of its costs and benefits. Thus, advertising could be utilized to pubic health officials’ advantage to change behavior to reduce the risk of obesity.

Since it is difficult to ban advertising from food companies, some efforts can be undertaken to minimize the occurrence of commercials for junk food and candy in television networks that are geared towards children or even when programming for children is on television. However, food companies may oppose and argue that their rights are being infringed upon. In addition to decreasing the occurrence of junk food and fast food commercials, a counter advertising campaign should be initiated.

Researchers should investigate the reasons as to why children consume large amounts of candy, junk food, and fast food. They should do this by organizing focus groups in school settings where it would be easy to recruit participants. Perhaps the reasons are a matter of taste preference, convenience, or because it is a food that they were able to choose on their own instead of something that their parents chose for them. Researchers must find the underlying reasons for children’s food choices. They then need to design an intervention that addresses these reasons so that children will change their behavior.

The intervention should entail a mass media campaign since the aim is to disseminate information to a large number of people. The media influences people’s views on issues and sets norms, such as displaying ways of dressing or examples of acceptable behavior. In addition, the media seeks to address group behavior instead of individual behavior because it looks at how a target population acts as a whole. They want to reach out to large numbers of people, not just one individual. The desired behavior of the intervention should be changing eating habits and choice of foods. Information will be disseminated through advertisements on television networks for children and during hours of children’s programming. In addition to television advertisements, public health officials should also consider advertising on internet sites that children visit often since so many children have access to computers. Advertisements should show that eating healthy foods is a matter of children’s own preferences, not their parents. It should be shown that children have power to make decisions and if they know more, they have more power and knowledge to make informed decisions. Children may not want to eat healthy foods because they are told what to eat and not because they want to eat a certain food. In addition, celebrities and athletes who are well-known among children and adolescents can act as spokespeople for the campaign because they have power to influence behavior since many serve as role models for children.

Conclusion

In order to effectively address the growing risk of obesity amongst children, a more effective intervention than BMI report cards needs to be undertaken. Handing out BMI report cards to children was ineffective because children have no sense of what the BMI scores and percentiles mean and it can lead to unwanted stigma of possibly being obese. In addition, larger social factors should have been considered. In contrast, a new intervention that addresses the flaws of the BMI report cards could help in the reduction of obesity amongst children. Instead of using BMI, waist-to-hip ratio has shown to be more accurate. Also, stigma can be avoided by not focusing on the individual and targeting public schools to change social expectations. Finally, an intervention to target childhood obesity should also contain a media campaign to change children’s behavior by instilling the idea that children have power to make their own decisions and by marketing healthy foods as desirable and socially acceptable.

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