Obesity means having excess body fat. For adults 35 and older, having a BMI greater than 30 is considered obese. Obesity is not just a cosmetic consideration. It is a chronic medical disease that can lead to diabetes, high blood pressure, heart disease, gallstones, and other chronic illnesses.
Obesity is difficult to treat and has a high relapse rate. Greater than 95% of those who lose weight regain the weight within five years. Even though medications and diets can help, the treatment of obesity cannot be a short-term "fix" but has to be a life-long commitment to proper diet habits, increased physical activity, and regular exercise.
The goal of treatment should be to achieve and maintain a "healthier weight," not necessarily an ideal weight. Even a modest weight loss of 5%-10% of initial weight and the long-term maintenance of that weight loss can bring significant health benefits by lowering blood pressure and lowering the risks of diabetes and heart disease.
The chances of long-term successful weight loss are enhanced if the doctor works with a team of professionals, including dietitians, psychologists, and exercise professionals.
What is obesity?
The definition of obesity varies depending on what one reads. In general, overweight and obesity indicate a weight greater than what is considered healthy. Obesity is a chronic condition defined by an excess amount body fat. A certain amount of body fat is necessary for storing energy, heat insulation, shock absorption, and other functions.
Obesity is best defined by using the body mass index. The body mass index is calculated using a person's height and weight. The body mass index (BMI) equals a person's weight in kilograms (kg) divided by their height in meters (m) squared. Since BMI describes body weight relative to height, it is strongly correlated with total body fat content in adults. An adult who has a BMI of 25-29.9 is considered overweight, and an adult who has a BMI over 30 is considered obese.
What Are the Definitions of Obesity for Adults and Children?
Overweight and Obesity Definition
Overweight and obesity are both labels for ranges of weight that are greater than what is generally considered healthy for a given height. The terms also identify ranges of weight that have been shown to increase the likelihood of certain diseases and other health problems.
Definitions of Obesity for Adults
For adults, overweight and obesity ranges are determined by using weight and height to calculate a number called the "body mass index" (BMI). BMI is used because, for most people, it correlates with their amount of body fat.
An adult who has a BMI between 25 and 29.9 is considered overweight.
An adult who has a BMI of 30 or higher is considered obese.
Definitions for Children and Teens
For children and teens, BMI ranges above a normal weight have different labels (overweight and obese). Additionally, BMI ranges for children and teens are defined so that they take into account normal differences in body fat between boys and girls and differences in body fat at various ages.
SOURCE: Centers for Disease Control and Prevention. Defining Overweight and Obesity.