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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Obesity

What is it?

Obesity is conventionally defined as an excess of stored fat resulting in a body weight that is 20 percent or greater than what is accepted as ideal for a person's height and body type. Though not itself a disease, obesity is a serious health risk.Mortality rates and the incidence of high blood pressure, coronary heart disease, and diabetes mellitus are substantially higher in obese adults, especially in those whose excessive fat is stored in the abdomen rather than in the hips. Excess weight increases the risk of gallbladder disease and may cause or aggravate arthritis by placing greater stress on the back, hips, and knees. Certain types of cancer may also be more common in overweight people. In addition, obesity is often accompanied by poor self-image, psychological distress, and diminished quality of life. Losing weight and keeping it off, however, is is extraordinarily difficult.

What Causes It?

  • Obesity results from an imbalance between caloric intake and energy expenditure, usually due to habitually excessive food intake and/or limited physical activity. Some people may gain weight because they have lower basal metabolic rates: they burn fewer calories to maintain body functions, such as breathing, heart contractions, and digestion.
  • Hereditary, environmental, and psychological factors all play a role in obesity.

Prevention

  • Establish healthy eating habits; maintain a nutritious, low-fat, high-carbohydrate diet.
  • Exercise regularly and stay as active as possible.

Diagnosis

  • Obesity is formally defined by a body mass index (BMI) greater than 30; overweight is defined by a BMI between 25 and 30. The BMI is calculated by dividing your weight in pounds by your height in inches squared, and then multiplying by 705.
  • Another approach compares a patient's weight to an ideal weight for their height and body type.
  • Blood tests are obtained to detect common complications of obesity, such as high blood levels of glucose and triglycerides.
  • Waist circumference is measured; a circumference greater than 40 inches in men or 35 inches in women indicates abdominal obesity.

How to Treat It

  • Your doctor or nutritionist may advise a diet of no less than 1,200 calories a day, made up of nutritious, low-fat, low-calorie foods (fruits, vegetables, whole grains, lean meat or fish, and low-fat dairy products).
  • Crash diets, fasting, and appetite suppressants (which may produce short-term weight loss, but rarely sustained weight loss) should be avoided.
  • Engaging in regular, vigorous aerobic exercise, such as running, biking, or swimming—or even walking or gardening—for at least 30 minutes a day four days a week is helpful.
  • Modest weight loss may be achieved with the prescription weight-loss drugs sibutramine (Meridia) or orlistat (Xenical). The drugs should be combined with dietary and lifestyle measures.
  • For grossly obese patients, doctors may advise a very low-calorie liquid diet (800 to 900 calories a day) with close medical supervision.
  • In rare cases when obesity can be life-threatening, doctors may resort to extraordinary measures, including surgery to staple the stomach and reduce its size, or cutting or suctioning away fat (liposuction). The long-term success of liposuction is questionable, and severe complications are possible.
  • Therapy or counseling may help to confront underlying psychological and emotional reasons for overeating. Support groups are often helpful.

When to Call a Doctor

  • If you are obese and unable to change your eating and exercise habits to lose weight, see a doctor or nutritionist.