Weight management refers to a set of practices and behaviors that are necessary to keep one’s weight at a healthful level.
It is preferred to the term “dieting,” because it involves more than regulation of food intake or treatment of overweight people.
People diagnosed with eating disorders who are not obese or overweight still need to practice weight management.
Some health care professionals use the term “nutritional disorders” to cover all disorders related to weight.
The term “weight management” also reflects a change in thinking about treatment of obesity and overweight during the past 20 years.
Before 1980, treatment of overweight people focused on weight loss, with the goal of helping the patient reach an “ideal weight”.
In recent years, however, researchers have discovered that most of the negative health consequences of obesity are improved or controlled by a relatively modest weight loss, perhaps as little as 10% of the patient’s body weight.
It is not necessary for the person to reach the “ideal” weight to benefit from weight management. Some nutritionists refer to this treatment goal as the “10% solution.”
Secondly, the fact that most obese people who lose large amounts of weight from reduced-calorie diets regain it within five years has led nutrition experts to emphasize weight management rather than weight loss as an appropriate outcome of treatment.
Overweight and obese
Overweight and obesity in the United States among adults and children has increased significantly over the last two decades.
Those following typical American eating and activity patterns are likely to be consuming diets in excess of their energy requirements.
However, caloric intake is only one side of the energy balance equation.
Caloric expenditure needs to be in balance with caloric intake to maintain body weight and must exceed caloric intake to achieve weight loss.
To reverse the trend toward obesity, most Americans need to eat fewer calories, be more active, and make wiser food choices.
Proper nutrition (eating a well-balanced diet) and daily physical activity are key components of a weight management program.
The basic principle underlying safe and effective weight loss programs is that weight can be lost only through a negative energy balance, which is produced when the caloric expenditure exceeds the caloric intake. The most effective way of creating a caloric deficit is through a combination of diet (restricting caloric intake) and exercise (increasing caloric expenditure)..
Weight is a major concern for many Americans. And there is good reason:
• Over 65 percent of American adults are overweight or obese.
• Most people who lose weight in traditional weight loss programs regain all of the lost weight within three to five years.
• Only 20 percent of all Americans get enough exercise to improve health and maintain healthy weights.
Overweight and obese are not the same thing.
People who are overweight weigh more than they should compared with set standards for their height.
The excess weight may come from muscle tissue, body water, or bone, as well as from fat.
A person who is obese has too much fat in comparison to other types of body tissue.
Hence, it is possible to be overweight without being obese.
Monitoring body fat regularly can be a useful strategy for assessing the need to adjust caloric intake and energy expenditure.
There are three surrogate measures used to approximate body fat are:
• Waist-to-hip ratio.
• Waist circumference (adults).
• BMI (adults and children).
Waist-to-hip ratio measures fat distribution.
Pre-menopausal women tend to store fat in the hips, buttocks, and thighs(Pear-shaped bodies)
Postmenopausal women tend to store fat higher in the upper body region and abdomen(Apple-shaped bodies).
Most men store fat in the abdominal area.
Excess fat stored in the upper body is associated with a higher risk of high blood pressure, diabetes, early onset of heart disease, and certain types of cancers than seen in subjects with excess fat stores in the lower areas of their bodies.
A waist-to-hip ratio greater than 1.0 in men and 0.8 in women indicates increased health risks, including hypertension, coronary heart disease, and type II diabetes.
Waist circumference (adults):
Measure around the waist while standing, just about the hip bones.
If it is greater than 35 inches(88 cm) for women or 40 inches(102 cm) for men, there is probably excess abdominal fat.
This excess fat may place one at greater risk of health problems.
BMI (adults and children):
The World Health Organization has formulated an index for defining obesity.
Known as the body mass index (BMI), it is based on the patient’s height in meters and weight in kilograms:
BMI = weight in kilograms ÷ (height in meters)2
This classification works for all patients except those at the extremes of height or muscle mass, where body proportions affect the calculation.
The BMI is calculated in English measurements by multiplying a person’s weight in pounds by 703.1, and dividing that number by the person’s height in inches squared.
BMI= (your weight in pounds x 703,1) ÷ (your height in inches)2
A BMI between:
• 19 and 24 is considered normal
• 25–29 is overweight
• 30–34 is moderately obese
• 35–39 is severely obese
• 40 or higher is defined as morbidly obese.
Goal of weight management
The purpose of weight management is to help each patient achieve and stay at the best weight possible the context of overall health, occupation, and living situation.
A second purpose is the prevention and treatment of diseases and disorders associated with obesity or with eating disorders.
These disorders include depression and other psychiatric disturbances, in addition to the physical problems associated with nutritional disorders.
Obesity is considered responsible for: 88–97% of cases of type 2 diabetes, 57–70% of cases of coronary heart disease, 70% of gallstone attacks, 35% of cases of hypertension, 11% of breast cancers, 10% of colon cancers.
Eating disorders are a group of psychiatric disturbances defined by unhealthy eating or weight management practices.
• Anorexia nervosa is an eating disorder in which persons restrict their food intake severely, refuse to maintain a normal body weight, and express intense fear of becoming obese.
• Bulimia nervosa is a disorder marked by episodes of binge eating followed by attempts to avoid weight gain from the food by abusing laxatives , forcing vomiting, or overexercising.
• A third type, Binge eating disorder, is found in some obese people, as well as in people of normal weight. In binge eating disorder, the person has an eating binge but does not try to get rid of the food after eating it.
Although most patients diagnosed with anorexia or bulimia are women, 40% of patients with binge eating disorder are men.
Causes of nutrition-related disorders
To understand the goals and structure of nutritionally sound weight management programs, it is helpful to look first the causes of being overweight, obesity, and eating disorders:
• Genetic/Biologic: Studies of twins separated at birth and research with genetically altered mice have shown that there is a genetic component to obesity. Some researchers think that there are also genetic factors involved in eating disorders.
• Lifestyle-Related: The ready availability of relatively inexpensive, but high-caloric snacks and “junk food” is considered to contribute to the high rates of obesity in developed countries. In addition, the fast pace of modern life encourages people to select quick-cooking processed foods that are high in calories, rather than making meals that are more healthful but take longer to prepare.
• Sociocultural: In recent years, many researchers have examined the role of advertising and the mass media in encouraging unhealthy eating patterns.
Advertisements for such items as fast food, soft drinks, and ice cream. Often convey the message that food can be used to relieve stress, reward, or comfort oneself.
On the other hand, the media also portray unrealistic images of human physical perfection.
• Medications: Recent research has found that a number of prescription medications can contribute to weight gain. These drugs include steroid hormones, antidepressants, benzodiazepine tranquilizers, lithium, and antipsychotic medications.
Aspects of weight management
The nutritional aspect of weight management programs includes education about healthful eating, as well asmodifying the person’s food intake.
Most weight-management programs are based:
• On a diet that supplies enough vitamins and minerals.
• 50–63 grams of protein each day.
• An adequate intake of carbohydrates (100 g)
• Dietary fiber (20–30 g).
• No more than 30% of each day’s calories from fat.
Good weight-management diets are intended to teach people how to make wise food choices and to encourage gradual weight loss.
Regular physical exercise is a major part of weight management because it increases the number of calories used by the body and because it helps the body to replace fat with lean muscle tissue.
Exercise also serves to lower emotional stress levels and to promote a general sense of well-being.
Good choices for most people include swimming, walking, cycling, and stretching exercises.
Both obesity and eating disorders are associated with a variety of psychiatric disorders, most commonly major depression and substance abuse.
Many people find medications and/or psychotherapy to be a helpful part of a weight management program.
In recent years, doctors have been cautious about prescribing appetite suppressants, which are drugs given to reduce the desire for food.
In 1997, the Food and Drug Administration (FDA) banned the sale of two drugs. Fenfluramine (known as “fen-phen”) and phentermine when they were discovered to cause damage to heart valves.
A newer appetite suppressant, known as sibutramine, has been approved as safe.
Another new drug that is sometimes prescribed for weight management is called orlistat. It works by lowering the amount of dietary fat that is absorbed by the body. However, it can cause significant diarrhea.
Cognitive-behavioral therapy (CBT) is a form of psychotherapy that has been shown to be effective in reinforcing the changes in food selection and eating patterns that are necessary to successful weight management.
Most CBT programs also include nutritional education and counseling.
As of 2003, bariatric surgery is the most successful approach to weight management for people who are morbidly obese (BMI of 40 or greater), or severely obese with additional health complications.
Surgical treatment of obesity usually results in a large weight loss that is successfully maintained for longer than five years.
The most common surgical procedures for weight management are:
• Vertical Banded Gastroplasty (VBG), sometimes referred to as “stomach stapling”
• and gastric bypass.
Vertical banded gastroplasty works by limiting the amount of food the stomach can hold. While gastric bypass works by preventing normal absorption of the nutrients in the food.
Complementary and alternative medicine (CAM) approaches
Movement therapies include a number of forms of exercise. Such as tai chi, yoga, dance therapy, Trager work, and the Feldenkrais method. Many of these approaches help people improve their posture and move their bodies more easily as well as keeping active. Tai chi and yoga, for example, are good for people who must avoid high-impact physical workouts.
The one type of alternative treatment that people should be extremely cautious in a weight management program is preparations advertised as “fat burners,” muscle builders, or appetite suppressants. In early 2003, the national media carried accounts of death or serious illness from taking these substances.
One is ephedra, a herb used in traditional Chinese medicine that can cause strokes, heart attacks, seizures, and psychotic episodes.
The other is usnic acid, a compound derived from lichens that can cause liver damage.