An Overview of Obesity in the U.S.
Obesity is a medical condition usually defined by a person's body mass index (BMI), but also used as a general term for persons who have an excessive amount of body fat. In recent years, there has been much concern over an obesity "epidemic," particularly in the United States, but also in parts of Europe and the Mediterranean. The World Health Organization (WHO) classifies anyone with a BMI higher than 30 as "obese," while those above 40 are "extremely" or "morbidly" obese. In addition to BMI, measurements such as waist circumference and body fat percentage are used to determine obesity. For men, 25 percent body fat is considered obese, while 30 percent is considered obese for women. None of the methods are completely accurate, and they are often combined to create a clearer picture of a particular person's risk factors.
Many people have argued that claims of an obesity epidemic are overblown or inaccurate, but do not deny that the medical conditions caused by obesity are indeed serious. As such, much of the concern over obesity has been whether the condition ought to be covered by health insurance. Hypertension and Type 2 (adult onset) diabetes are two of the most serious conditions associated with obesity, though heart problems are also frequently caused by obesity, as are respiratory problems and some cancers. Nevertheless, the term "epidemic" is seen by many as a misnomer, invoked more for its shock value than its accuracy in describing the state of obesity in the country.
Critics of the rhetoric of obesity tend to claim that the stigma against obesity's based on existing biases against decadence or laziness or gluttony, of which obesity is seen as a necessary outcome. Thus, they say, many people view obesity as a symptom of an existing problem. These critics claim that the stigma of obesity is based on preconceptions about the nature of obesity, rather than genuine concern about the dangers of the condition.
As with almost any behavior or condition that is not fully understood, the question of nature versus nurture is raised in the obesity debate, particularly because there is no way to determine whether inherited obesity is caused by the passing on of genes or the passing on of eating and exercising habits. Both genetics and behavioral factors have been blamed for childhood obesity, and no one seems to be entirely certain which factors contribute to obesity the most, thus leading to differing viewpoints.
Basic Terms, Concepts, and Definitions Related to Obesity
Body Fat: The amount (usually expressed as a percentage) of fat in a person's body. Body fat plays an important role in human health, and some is necessary for maintaining many bodily processes and functions, such as regulating temperature, providing cushioning, and insulating organs. Too little body fat (less than 10 percent in women, or less than 2 percent in men) is unhealthy, because it impairs these functions, while too much (more than 30 percent for women, more than 25 percent for men) is also unhealthy, because it overtaxes the body and organs.
Body Mass Index (BMI): An expression of weight in kilograms divided by height in meters squared. Because BMI does not directly measure body fat, it is not entirely accurate for determining obesity, especially since muscle weighs more than fat, making it possible for a very muscular person to have a higher BMI than an obese person.
Epidemic: Medically, an epidemic is a disease in which new cases appear in numbers far greater than what is expected. Used metaphorically, an epidemic can refer to any condition or behavior that spreads like a medical epidemic.
Obesity: Generally, an extreme excess of body fat. Persons in the 95th percentile of weight, or with a BMI of 30 or more, or with more than 30 percent (25 percent for men) body fat, are usually considered obese. Obesity occurs when more calories are consumed than are burned. However, the rate at which calories are burned varies widely between persons, and for a number of reasons, so no one cause can be definitively blamed for obesity. Overweight: A less-technical term than "obese," overweight is a term that is usually applied to persons with a BMI above 25. Unlike obesity, which deals specifically with body fat, overweight can refer to any excess weight, whether caused by fat, muscle, bone, or water.