Anyone who is over age 40 or has health problems should have a thorough medical evaluation prior to beginning a weight loss program. In addition, your physician may refer you to a nutritionist for an assessment of eating habits.
1. Medical history
The medical history will include the following:
Weight history. Your physician will determine how long you have been overweight, because obesity present since childhood may reflect a genetic predisposition and is often more difficult to treat than adult-onset obesity. Other questions may address dieting history:
Medical history. Do you have any symptoms or history of obesity-related disorders (such as CHD, stroke, hypertension, cancer, or diabetes)? Are there any symptoms suggesting an endocrine cause of obesity, such as hypothyroidism?
Family history. Is obesity prevalent in your family? Is there a family history of any obesity-related disorders?
Medications. Drugs that can cause weight gain, increase appetite, or hinder weight loss include corticosteroids, progestins, tricyclic antidepressants, phenothiazines, lithium, sulfonylureas, thiazolidinediones, and insulin.
Depressive symptoms. Depression affects many overweight people, especially those who are severely obese. A thorough evaluation includes questions about mood to determine whether depression needs to be treated along with obesity.
2. Physical examination
Blood pressure, height, weight, and waist circumference are measured. The physician will look for evidence of cardiovascular disease (diseases of the heart and blood vessels), osteoarthritis, and hypothyroidism or other hormonal conditions.
Obesity is often defined as weighing 20 percent or more above ideal body weight (which varies with height, age, and gender). This definition is somewhat misleading, however, since it is not the amount of excess weight but the amount of excess adipose tissue--or body fat--that determines the threat to health. Moreover, the distribution of body fat is an important predictor of health risk--fat stored in the abdominal area is more harmful than fat stored in the hips, thighs, and buttocks. The degree of obesity is also important; a mildly obese person is at less risk for developing obesity-related conditions than someone who is morbidly obese.
In addition to height, age, and gender, a person's ideal weight depends on many factors, including body composition (the proportion of fat and muscle), body shape (where fat is deposited), and general health. The most accurate way to assess the degree of obesity is to measure the amount of body fat. Since this task is not easy to perform, doctors generally rely on surrogate measures, such as body mass index and waist circumference, or use height/weight tables.
This section has more on weight assessment methods.
