Obesity is a continuing epidemic in America today, but a surprising result was found in a recent survey conducted by the RAND Corporation. It was found that the percentage of Americans who are classified as severely obese—more than 100 pounds overweight—is growing twice as fast as those who are moderately obese. "The proportion of people at the high end of the weight scale continues to increase at a brisk rate despite increased public attention on the risks of obesity and the increased use of drastic weight loss strategies such as bariatric surgery," said Roland Sturm, an economist at the RAND Corporation and author of the report that is scheduled to be published later this year in the journal Public Health.
The data for this study was gathered from the CDC's annual Behavioral Risk Factor Surveillance Survey (BRFSS), a phone survey of nearly 1.5 million respondents across the country. The classification for obesity was based of a person's Body Mass Index (BMI), which is defined asweight in kilograms divided by the square of height in meters—a BMI of over 30 is obese, and a BMI over 40 was considered severely obese. Weight and height were self-reported in the study, which should lead to understated BMI values. The study found that only three percent of the populous was already severely obese, but their numbers are growing faster than any other category. Between 2000 and 2005, the proportion of Americans with a BMI of greater than 30 grew by 24 percent, those with a BMI of greater than 40 grew by 50 percent, and those with a BMI of more than 50 increased by 75 percent. To put actual numbers on that, a 5'10" male with a BMI of 30 would weigh 210 pounds, BMI of 40 would be 280 lbs, and a BMI of 50 equates to 350 pounds.
One can easily have issues with the use of BMI alone to dictate obesity. Generally the BMI is good for measuring trends in a large population(which is done in this survey), and is not as useful when discussing the value for a single individual. This is because BMI isn't the most accurate measurement for defining how over/under weight you. BMI is a ratio of your weight to a surface area. Other methods, which require more data, such as the Navy circumference method give more accurate results as to how over/under weight a person is, as it takes frame size into account. For instance, using myself as a metric, according to BMI calculators my ideal weight (BMI of about 22) is around 170 pounds; if I use the Navy method, which factors in my sex and my neck and waist size; my ideal weight is closer to 225 pounds, or greater than a 50-pound difference. This highlights an issue with using BMI to define obesity for an individual: it does not take into account body frame size.
Regardless of the metric used, it has been shown that obesity costs the health care industry enormous amounts of money each year. A middle-aged American with a BMI of over 40 has been shown to have double the health care costs of a normal weight individual, and those who are moderately obese have a 25 percent rise in health care costs. While a normal calorie diet and moderate exercise is a guaranteed way to maintain your weight, modern medicine has given hope to those who have become severely obese. Bariatric surgeries—those that surgically alter the amount of food one can physically eat—have exploded in recent years. In 1998 there were an estimated 13,000 procedures; six years later, in 2003, there were more than 100,000 such procedures. It is estimated that 2006 saw more than double that, 200,000, however it has little effect. "The explosion in the use of bariatric surgery has made no noticeable dent in the trend of morbid obesity," Sturm said. This study suggests that those who are the most obese are not a fixed percentage of the population, as was once thought, but they are increasing at a rapid rate and must be viewed as an integral part of the population's weight distribution.