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Obesity traditionally has been defined as a
weight at least 20% above the weight corresponding to the lowest
death rate for individuals of a specific height, gender, and age
(ideal weight). Twenty to forty percent over ideal weight is
considered mildly obese; 40-100% over ideal weight is considered
moderately obese; and 100% over ideal weight is considered severely,
or morbidly, obese. More recent guidelines for obesity use a
measurment called BMI (body mass index) which is the individual's
weight multiplied by 703 and then divided by twice the height in
inches. BMI of 25.9-29 is considered overweight; BMI over 30 is
considered obese. Measurements and comparisons of waist and hip
circumference can also provide some information regarding risk
factors associated with weight. The higher the ratio, the greater
the chance for weight-associated complications. Calipers can be used
to measure skin-fold thickness to determine whether tissue is muscle
(lean) or adipose tissue (fat).
Much concern has been generated about the
increasing incidence of obesity among Americans. Some studies have
noted an increase from 12% to 18% occurring between 1991 and 1998.
Other studies have actually estimated that a full 50% of all
Americans are overweight. The World Health Organization terms
obesity a worldwide epidemic, and the diseases which can occur due
to obesity are becoming increasingly prevalent.
Excessive weight can result in many serious,
potentially life-threatening health problems, including hypertension,
Type II diabetes mellitus (non-insulin dependent diabetes),
increased risk for coronary disease, increased unexplained heart
attack, hyperlipidemia, infertility, and a higher prevalence of
colon, prostate, endometrial, and, possibly, breast cancer.
Approximately 300,000 deaths a year are attributed to obesity,
prompting leaders in public health, such as former Surgeon General
C. Everett Koop, M.D., to label obesity "the second leading cause of
preventable deaths in the United States." |
