Medical Management of Obesity

Obesity is a chronic syndrome that may be caused by many factors, including genetics, endocrine regulation of appetite, metabolism, as well as psychological and cultural factors. It is the most common health problem in developed countries throughout the world.

There are many conditions, such as diabetes, coronary heart disease, high blood pressure and heart failure, that may be caused or made significantly worse by obesity. Though the cosmetic benefits may appear slight, even small (but permanent) weight losses of 5 to 10 percent in obese people may improve the symptoms of these other "comorbid" conditions or prevent their occurrence. In fact, permanently adopting a healthy lifestyle should be the primary goal, rather than simply losing weight.

The first step in managing obesity is determining the patient's body mass index (BMI). This is computed based on the patient's height and weight. Individuals with a BMI of 25.0-29.9 are classified as overweight. Those with a BMI of 30.0 or higher are considered obese; a BMI of 40.0 or higher indicates extreme obesity.

Adults who have a BMI of 25.0-34.9 and a waist circumference of 40 inches or more in men or 35 inches or more in women are at increased risk for developing obesity-related health problems. BMI tables, however, do not apply to certain populations, such as frail and sedentary elderly, pregnant or lactating women, growing children and individuals with high muscle mass such as body builders.

In addition to the BMI, a patient's specific obesity history is important for proper diagnosis. Some conditions, such as hypothyroidism, and medications, such as steroids and tricyclic antidepressants, promote weight gain. Psychological conditions, including stress, anxiety and depression, may promote weight gain, as does menopause.

Family history (genetics) and the chronology of weight gain should be taken into account. Was it progressive since adolescence? Was it a sudden weight gain, perhaps because of changes in diet or activity? Or is the individual regaining weight after a successful weight loss? A small portion of patients may not be good candidates for weight loss because of existing health issues.

Diet and Exercise

An effective treatment strategy should focus on developing a healthy, long-term lifestyle including physical activity and appropriate eating habits. A 10% reduction from beginning body weight over a period of four to six months is reasonable, but different goals are appropriate for different patients. Because the body accustoms itself to changes, the rate of weight loss often stabilizes after six months. But a healthy lifestyle is designed for a life time. Unless permanent changes in lifestyle are made, lost weight will most often be regained.

Treatment usually begins with a detailed accounting of the patient's eating and activity habits. Many people are not aware of exactly what they're eating and how it affects their weight. For example, a patient may eat a low-fat diet but drink two liters of regular soda each day and not exercise.

With consultation of a dietitian and exercise therapist or athletic trainer, a treatment regimen may be designed to create an energy deficit in which the calories consumed are less than the calories expended through physical activity.

An energy deficit of 300-500 calories per day will produce weight losses of 0.5 to 1 lb. per week. An energy deficit of 500-1,000 calories per day will produce weight losses of 1 to 2 lbs. per week. However, a diet with less than 1,300 calories is not recommended for long term use because it may not provide enough nutrients. Diets that cause a loss of more than 2 lbs. a week are generally so restrictive they cannot be maintained for a lifetime, resulting in weight being regained. These include "fad" diets such as grapefruit, cabbage, and high-fat, high-protein diets.

Dietary therapy should be individualized to the patient's lifestyle, satisfy key nutritional needs, minimize hunger and fatigue, be readily obtainable, establish new eating habits and improve overall health. A reduction in total fat consumption is also recommended.

Guidelines set by the American Diabetes Association and American Heart Association (step 1 or 2 diets) recommend eating a variety of foods comprising a diet that includes carbohydrates (50-60%) and fat (20-30%) with the remainder made up of protein.

Decreased caloric intake is responsible for most weight loss. However, physical activity is responsible for increased caloric expenditure and may promote compliance with dieting and reduce the desire for foods that are high in fat. Physical activity includes not only a formal exercise regimen but changes in daily routines, such as climbing stairs rather than taking the elevator, walking to a destination versus driving, or performing more household chores (vacuuming, gardening, or mowing the lawn). Even chewing sugarless gum throughout the day can burn calories. Regular daily exercise will help maintain weight loss by preventing weight gain.

For overweight patients, intense exercise may be difficult. In that case, the length or duration of exercise should be emphasized. Instead of walking fast for 20 minutes, walk slowly for longer. As an added workout to aerobic exercise (such as walking or biking), weight-lifting can increase muscle mass, which burns more calories, even when resting.

Finding emotional support from family, friends or social groups is important. Whether finding an "exercise buddy" or joining a group that provides a social setting for exercise (walking clubs, bike groups, canoeing clubs, etc.) can be a big help.

Medications

There is no magical pill for weight loss, but sometimes medications are prescribed to help lose weight in the short-term. Generally, they are used only after significant changes in diet and physical activity have been unsuccessful or other medical conditions are present.

Xenical, Meridia, and types of amphetamines are the most commonly used weight-loss drugs. Xenical has fewer serious side effects and is safer than the other obesity drugs. Xenical blocks the absorption of dietary fat in the intestine and works well with a low-fat diet, but eating fatty foods will cause intestinal problems such as diarrhea.

Meridia works in the brain and nervous system, most likely resetting the body's thermostat to burn more calories or by suppressing appetite. It can lead to high blood pressure, however. Amphetamines decrease the hunger drive and increase the body's ability to burn calories when resting, but may also cause high blood pressure or even a form of addiction.

Still, permanent lifestyle changes including a low-fat diet and daily activity are the key to successful, long-term weight loss.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.