Body Mass Insanity. sources, obesity has been categorized as the epidemic Americans are facing at an accelerated

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1 Hildebrand 1 Marshane Hildebrand Professor Jeff Moulton Engl March 2013 Report Rough Draft Body Mass Insanity According to reports that have been circulated around the internet and other news sources, obesity has been categorized as the epidemic Americans are facing at an accelerated rate. These sources claim that obesity is quickly becoming the nation's leading health issue. Evidence suggests that by the year 2030, the obesity rate within America will reach beyond fifty percent of the population (Braun, 1). This progression not only threatens to impair the health of millions, it has been linked to the possible onset of many diseases, the surge in health care expenses and greater federal intervention in the health of American citizens. In light of these concerns, who determines what is considered obese and what tools are being implemented to distinguish a healthy weight versus a hazardous weight? The classification for determining obesity began back in the early 1800's with the help of a social statistician named Adolphe Quetelet. Quetelet was a Belgian scientist with a passionate interest in the physical characteristics and social abilities of humans. A Renaissance man of his time, Quetelet's main interest was in developing the first body index which had little to do with obesity. His concern was in defining the characteristics of the 'normal man' and applying the assessments around this norm (Eknoyan 49). Quetelet had a difficult time illustrating a relationship between height and weight, so he began conducting a cross-sectional study on newborns and children, which eventually lead to adults in His conclusions ultimately

2 Hildebrand 2 led to the production of his book, Treatise of Man, which is dedicated to the growth rates and correlations of height and weight throughout the many stages of life. To summarize his findings, if man increased equally in all dimensions, his weight at different ages would be as the cube of his height (49). While over indulgence was affiliated with wealth and better living standards throughout the 18 th and 19 th century, it wasn t until the early 20 th century when obesity became a object of documentation by the insurance industry. Louis I. Dublin, statistician and vice president of Metropolitan Life Insurance Company (MLIC), began to develop tables and charts that clarified normal weights for a given height based on longevity statistics from over 4.9 million policies issued to adults between the ages of (Pekar, 21). The problems that arose from these tables were the wide ranges of weights accumulated from individuals of the same sex and height. In order to adjust for the differences, Dublin divided the distribution of weight at a given height into thirds resulting in small, medium and large body frames. The ideal body type was the average between the other two extremes, which later became the desirable weight for all frame types for insurance purposes. Ranges from for men and for women became the ideal BMI readings recommended (Pekar, 21). Although Dublin established a key aspect in the Body Mass Index (BMI), the charts lacked critical information. For instance, only wealthy individuals were able to afford insurance at the time, the data collected was based on the Caucasian population and insurance policies could be terminated for other reasons besides health (21). Today's standards for an optimal weight were established from the published work of American scientist Ancel Keys. Keys' work on correlation of the BMI with weight-gain and height has simplified the assessment of obesity, compared to the Met Life charts that health officials tried to popularize. Although Keys revamped Quetelet s original index, he only meant it

3 Hildebrand 3 as a guideline when considering body weight, and to be used for epidemiological studies (Pekar, 22). The Body Mass Index is used for the evaluation of health, disease risk, and interpretation of population studies. Obesity is currently defined as a BMI reading of 30 or above for a body fat percentage. The equation originated with Quetelet is still used today, weight in kilograms and divided by the square of height in meters. Several versions of this index have been used throughout history to shape relative body weight for health statistics versus unhealthy statistics. While body weight and height can help determine a general health status, the BMI charts are challenged as an inconsistent source for determining overall health risks. The Center for Disease Control (CDC) states that BMI is a fairly reliable indicator of body fatness for most people. Although it does not measure body fat directly, research shows that it correlates to direct measures of body fat, like underwater weighing or dual energy x-ray absorptiometry (CDC). Using BMI for weight-height measurement does not give accurate information about body composition. Athletes can be classified in the overweight to obese ranges because muscle mass weighs more than body fat. The index also doesn t take into account the overall total adiposity and only correlates a percentage of fat with the body. Assumptions are that if a person has a certain weight at a certain height with an over-fat percentage, then they fall in the overweight to obese range. An additional key issue with the index is the constant changes it has endured since it came into existence. In the beginning, values were determined by observing a population distribution of measured weight versus morbidity or mortality outcomes. Between 1959 to 1980, the MLIC weight-for-height tables were used to determine ideal body weight when purchasing insurance policies (Flegal, Kuczmarski 1075). These tables connected weight-to-height low

4 Hildebrand 4 death rates, but not essentially the lowest morbidity. In 1980, the US Department of Agriculture and the Department of Health and Humans Services jointly issued the Dietary Guidelines for Americans, which included tables that were sex-specific for given heights. The BMI units used for above ideal weights were rating for men and rating for women. These values were modified versions of the weight charts used by MLIC, which used the minimum values for small frames and maximum values for larger frames, but were still approximations of MLIC s ideal desirable weight (Flegal, Kuczmarski 1075). In 1984, the President as well as Congress received an official annual report called the Health United States, which listed overweight estimations for the ages of using two weight-for-height indexes. Body Mass Index was used for men confirming that anything greater than 28 was considered overweight, and for women the Benn p factor was used in defining overweight as anything greater than 35.0kg/m 1.5. This new power component of 1.5 was used for women to correlate adiposity with the theory of it being independent of height. Yet the assumption fell flat because BMI had a higher correlation on adiposity for both men and women via percentages (Flegal, Kuczmarski 1076). Throughout the 80 s to present, the BMI chart, health guidelines and journals constantly re-defined weight standards known as ideal, desirable, overweight and obese. A perfect example would be changing the weight cut-offs for obesity to greater than 25. This assessment would increase the number of overweight adults from 61.7 million (previous BMI ) to 97.1 million. This reflects a 35.4 million increase in overweight adults, and represents how the shift of the BMI criteria can alter guideline information incorrectly, and cause a epidemic alarm (Flegal, Kuczmarski 1078).

5 Hildebrand 5 Another aspect to consider when using the Body Mass Index is whether it reflects predictive information about obesity for health diagnoses. Obesity is clearly linked to higher incidence of hypertension, type 2 diabetes, hypercholesterolemia, heart disease, stroke, asthma, and arthritis, an obese worker or family member of a covered worker will incur, on average, substantially higher medical costs than healthy-weight individuals (Nicholas, Yang 382). The current representation of the index is set up as guideline for easy assessment. Table 1: By rounding the numbers to easier and more memorable stats, such as 25 and 30 for overweight categories, medical staff and physicians can effortlessly diagnosis possible health concerns to look out for. An example of how the chart works in favor with the medical industry, would be a patient that has been calculated in the 25 range for their current weight and height, and a physician advising a possible connection to certain health risks, such as hypertension or

6 Hildebrand 6 diabetes, if the patient keeps gaining weight. Even the CDC confirms that calculating BMI is one of the best methods for population assessment of overweight and obesity. Because calculation requires only height and weight, it is inexpensive and easy to use for clinicians and for the general public (CDC). Opinions seem evenly divided on the BMI; many doctors and nutritionists consider it a valuable tool in diagnosis and treatment, while researchers claim the chart is not only misleading and inaccurate. Assumptions regarding the relationship between general health and weight based on BMI categories are almost certainly wrong. In some cases, the mortality rates for patients is actually lower for the so-called obese than for those labeled as desirable in weight. In the context of this information, it is reasonable to consider whether the BMI measurements are genuinely reflective of health problems, or if they are simply a means of enforcing an aesthetic standard or generating income for insurance companies.