Obesity/Weight Loss

Diagnosis

Basics

Obesity is a chronic disease. Being overweight is defined as having a body mass index (BMI) of 25.0 to 29.9, while obesity is defined as having a BMI of 30.0 or above [Figure 1]. Your body mass index (BMI) is a measurement that is derived from a calculation of your weight relative to your height. Your BMI correlates fairly well with the amount of total body fat that you have.

Being overweight or obese is hazardous to your health. In 1985, the US Surgeon General warned that as a result of being overweight or obese, 34 million Americans were at risk for developing heart disease, stroke, diabetes, and cancer. Since then, the numbers of Americans at risk has almost tripled. According to the 1998 National Heart, Lung, and Blood Institute report, over one-half of all Americans are now overweight or obese. Recent estimates attribute about 112, 000 deaths each year in the US to obesity, making it second only to cigarette smoking as a cause of death.

Medical disorders such as high blood pressure, high cholesterol levels, and gallbladder disease are associated with obesity. Obesity has been shown to increase the risk of developing high blood pressure, adult-onset diabetes, heart attack, stroke, degenerative joint disease of the back and knees, gallstones, and certain forms of cancer such as that of the breast, prostate, and colon. Obese women commonly can have infertility problems, irregular menstrual flow, and urinary incontinence.

The good news is that losing as little as 10% of your current weight will help to lower your risk of developing certain obesity-related diseases. One recent study, for instance, indicates that a modest loss of 5% to 10% of body weight can lower blood pressure and reduce your risk of developing diabetes.

Affected individuals should seek treatment through clinical programs provided by licensed health care professionals. Bariatric physicians are specialized in treating obesity and its related diseases. Treatment is also offered through nonclinical commercial enterprises such as Weight Watchers, Jenny Craig, and Nutrisystem.

Figure 1. BMI calculator (enlarged at end of this document - HA)

 

Causes

Obesity is a chronic disease caused by an interaction between genes and the environment.

Obesity is caused by an energy imbalance that occurs when a person consumes more calories than he or she burns through physical activity. If you consume more calories than you burn, you will gain weight. Conversely, if you burn more calories than you consume, you will lose weight. Knowing that, why so many people consume more calories than they can burn is unknown. For most people, it isn't because of gluttony, lack of willpower, or laziness. Almost everyone who is overweight or obese has tried to lose weight, been temporarily successful, but failed to keep the lost weight and more from returning. Why is it so difficult to lose weight and keep it off? Scientists have only partial answers. They are still trying to sort out the complex interactions between genetic makeup and the environmental causes of obesity.

Obesity has a strong genetic component, and tends to run in families. Family members share not only genes, but also diet and lifestyle habits that can contribute to obesity. In one study of adults who were adopted as children, researchers found that the subjects' adult weights were closer to their biological parents' weights than their adoptive parents. Apparently, in that study genetic makeup had more influence on those person's adult weights than did the environment provided by the adoptive family. Some experts estimated that 60% of our obesity is caused by genetic makeup, and 40% is caused by environmental factors.

Environmental factors also play a significant role in causing obesity. The availability or lack of food, as well as economic status, are environmental factors that contribute to obesity. Environmental factors also include lifestyle behaviors such as what and how often you eat, and how active you are. Americans tend to like to eat a high-fat diet for reasons of taste and convenience. Also, many people, at least those in affluent industrialized countries, aren't physically active enough.

Many people eat in response to negative emotions such as anger, boredom, or sadness. However, most overweight people have no higher rates of diagnosed psychological disorders than people of normal weight.

Some prescription drugs and certain illnesses can cause or contribute to obesity. Hypothyroidism, Cushing's syndrome, and certain psychiatric and neurological problems can lead to weight gain. Certain drugs, including steroids and many medications used to treat psychiatric diseases such as depression, bipolar disorder, and schizophrenia, can cause excessive weight gain.

Symptoms

For most people, weight gain leading to obesity occurs gradually, over a period of years. As you gain weight, you will notice that your clothes feel tight, and no longer fit. However, symptoms of being overweight and obese can be more serious than just noticing that your clothes are tight.

Being overweight or obese can lead to joint pains, primarily in the low back, hip, and knee joints. People who are overweight are also more prone to develop carpel tunnel syndrome, and to develop rashes and fungal and bacterial infections of the skin. Overweight women have a higher chance of developing urinary incontinence, irregular menstrual cycles, and infertility. People who are overweight also get short of breath during exertion.

Many overweight and obese people suffer from sleep apnea, a condition characterized by moments during sleep when breathing ceases. This can occur as often as hundreds of times per night and, if untreated, can lead to cardiovascular problems and premature death. Individuals with sleep apnea often feel very tired, even during the day.

Risk Factors

A combination of genetic and environmental influences are considered to be risk factors for weight gain and obesity. People with a family history of certain diseases, including heart disease and diabetes, are more likely to become obese and develop those same problems once obese. High blood pressure, high cholesterol, or high blood sugar levels are all warning signs of obesity-related diseases.

For some women, pregnancy is a major risk factor for obesity. Although most women weigh only a few pounds more after pregnancy, about 15% of women put on an additional 10 pounds with each pregnancy.

Underactive hypothyroid glands (hypothyroidism) have traditionally been thought to be a common cause of obesity. Of late, however, scientists feel that hypothyroidism rarely causes obesity because most obese patients who are treated for hypothyroidism do not lose their excess body weight.

Overfeeding during infancy and an increase in fat cells and connective tissue that stores fat (adipose tissue) during infancy and childhood has been shown to predispose children to obesity later in life.

Growing up poor limits access to high-nutrient, non-fatty foods. Therefore, being poor is an important risk factor for obesity; particularly for women.

Leading a sedentary lifestyle is a risk factor for obesity. Physical activity not only increases your energy, but also helps to control your appetite.

Using prescription drugs on a long-term basis has recently been recognized as a risk factor for obesity. Steroids and psychoactive drugs including traditional antidepressants (tricyclics, tetracyclics, and monamine oxidase inhibitors) and benzodiazepines, lithium, and antipsychotic drugs can cause weight gain.

Diagnosis

You can determine whether or not you are overweight by measuring your waist circumference and calculating your BMI [Figure 1][Figure 2]. Having a BMI of over 30 kg/m² indicates that you are obese. A BMI in the range of 25 to 29.9 indicates that you are overweight, while a BMI in the range of 18.5 to 24.9 represents a normal, healthy weight. Since muscle weighs more than fat, you could have a high BMI if you are very fit and muscular. However, examples like these are relatively rare except in bodybuilders and football players.

If you have excess fat in your abdominal area rather than in your hips and thighs, you are also at a higher risk of developing diabetes, high blood pressure, heart disease, and other diseases. For women, risk increases when your waist is more than 35 inches around. For men, risk increases when your waist is more than 40 inches around.

People who have BMIs of 25 or more or high waist measurements and who also have two or more of the listed risk factors are strongly encouraged to lose weight.

Your waist-to-hip ratio helps to determine your risk of death from heart failure. Recent studies indicate that the disposition of fat around the trunk is associated with increased risk of dying from heart failure. The distribution of fat is assessed by calculating a waist/hip ratio. In other words, measure your waist circumference, and divide it by your hip circumference. Men who have a ratio greater than 1.0, and women with a ratio greater than 0.8 are at highest risk for heart failure.

Figure 2. Waist Measurement (enlarged at end of this document - HA)

If you have excess fat in your abdominal area (“apple” shape; woman on right) rather than in your hips and thighs (“pear” shape; woman on left), you are at a higher risk of developing diabetes, high blood pressure, heart disease, and other diseases. For women, risk for diabetes increases when your waist is more than 35 inches around. For men, risk increases when your waist is more than 40 inches around.

Prevention and Screening

Children should be taught healthy and nutritious eating and physical activity habits at an early age. Children, teens, and young adults should be taught to identify and overcome barriers to healthy eating and exercise. Studies show a direct correlation between the amount of television children watch and their body weight. Thus, children should be encouraged to watch TV less and exercise more.

Prevention efforts aimed at children, when supported by adults, can be successful. Although there is an epidemic of childhood obesity in the US, studies show that overweight children who lose excess weight are more likely to keep it off than are adults. In addition, studies show that it is easier to teach and motivate children to eat well and exercise than it is for adults to adopt similar behaviors later in life.

Treatment

Self Care

Fad diets might help you lose weight, but few people manage to keep off the lost pounds. If you have tried diet after diet, but have never managed to keep off the weight you lost, you are not alone. Most people return to their pretreatment weight within five years. This is because obesity is a chronic disease, just like diabetes and hypertension. There is no quick cure. You need lifelong treatment and lifelong commitment. Most people can go on certain fad diets for duration of time and may lose weight. However, when they go off their diets and loss their motivation, they gain back their weight.

Especially questionable are the popular high-protein diets. Because of their high fat and cholesterol content, most medical professionals do not consider high-protein diets to be safe or effective over the long term.

Diet programs need to be used in conjunction with exercise and behavioral modification in order to work. For some people, based on their degrees of obesity, medications prescribed by medical doctors for weight loss may be beneficial. Most weight control experts recommend the following guidelines, which are published in the new fifth edition of the US Department of Agriculture book, Dietary Guidelines for Americans:

• Aim for a healthy weight
• Choose a variety of grains daily, especially whole grains
• Choose a variety of fruits and vegetables daily
• Choose a diet that is low in saturated fat and cholesterol and moderate in total fat.
• Choose and prepare foods with less salt to prevent hypertension
• Choose beverages and foods with moderate amounts of sugar
• If you drink alcoholic drinks, do so in moderation
• Be physically active each day

Behaviorists emphasize that overweight people can change themselves, but that doing so involves making permanent lifestyle changes. Changing your habits means learning new skills, including identifying triggers for overeating, and finding ways to deal with your own emotional states, your environment, and with other people who might be encouraging you to overeat.

Identify situations that trigger the urge to eat. Once you identify them, you can eliminate the trigger.

Among the many overeating triggers are:

• Eating place. Certain locations become associated with eating. For instance, some people always eat in the kitchen. One bariatric doctor tells of a patient who would come home after work, park her car, enter her home through the back door to the kitchen, and go directly to the refrigerator for a snack. She broke that pattern by altering her route. On arriving home, she entered through her front door and went directly to her bedroom to wash up and change clothes. By avoiding the kitchen until mealtime, she avoided triggering her hunger.
• Social situations. Some people always eat while visiting certain friends who encourage them to try “special recipes.” Such situations can be avoided by learning assertiveness skills in order to refuse the tempting creations. Being assertive doesn't mean being aggressive. Assertive people are those who act in their own best interest, are able to express their feelings clearly and honestly, and accept responsibility for their own actions. They can choose to refuse food when it is offered without feeling guilty and without offending. A statement such as, “thanks, but I really don't want any” asserts your wish without hostility.
• The sight, smell, and thought of food can also be an overeating trigger. The sound of the ice cream truck's music or commercials on TV can inspire cravings. Those cravings can be calmed. First, tell yourself, “I don't need what I want.” Then engage in some activity that will take your mind away from the craving.
• Emotional states also drive many people to overeat. Anger, stress, hostility, frustration, and even boredom can induce feelings many of us interpret as the beginnings of hunger. Recognize that emotions can induce hunger, and guard against them by having a plan about what to do when they occur. You might develop a new habit such as taking a walk or lifting hand weights, or hitting a punching bag or a pillow. If the situation involves someone else, you might want to call “time out” and leave the situation. If you are bored, you might want to go see or call a friend. The key is to change your environment and do something else instead of eating. You don't have to use food to allay tension, anxiety, boredom, or other problems. At one time, you learned to use food in those situations. You can learn other, healthier behaviors.

Reward yourself when you avoid eating triggers. When attempting to make major habit changes, rewards are essential. Learn to give yourself a well-deserved pat on the back or other reward when you recognize that you have avoided a trigger that used to cause you to overeat. Don't forget to give yourself tangible rewards. Buy yourself a ticket to a concert or a play; buy a CD or an exciting book. Do whatever it takes to give you a good feeling.

Increase your physical activity. Increasing your level of activity reduces your risk of heart disease, high blood pressure, osteoporosis, diabetes, and obesity. Exercising also contributes to mental well-being, helps you sleep better, increases energy and endurance, and relieves stress, anxiety, and depression. Exercise also keeps joints, tendons, and ligaments flexible so it's easier to move about.

Experts advise adults to spend 30 minutes or more on moderate-intensity physical activity on most, if not all the days of the week, or to do 20 minutes or more of vigorous activity at least three times a week. Build up gradually. Every additional five or ten minutes of activities such as walking or lifting weights can be helpful. Don't try to do too much at once. Forget the “no pain, no gain” cliché. If it hurts, stop. Ask your doctor or a physical therapist for advice.If you have any doubts about your ability to exercise, check with your doctor.

Frequently, when people begin to exercise, they do too much too fast. That can result in muscle aches, joint pain, and injury. The key is to gradually increase your activity levels in a slow, step-by-step progression that can be easy and painless. If you have not been active, start with just five or ten minutes of increased activity each morning. Understand that every move you make with your body is an exercise. The more active you become, the more calories you burn, thus eliminating fat.

Look for fitness opportunities in everything you do. When you talk on the phone, stand up. Get up to change the TV channel instead of using a remote control. Don't look for the closest parking place to wherever you are going. In fact, look for one that will give you an opportunity to walk. When you have a choice, walk instead of ride to where you are going. Take the stairs instead of the elevator. If you ride the bus, get off one stop earlier and walk the rest of the way. Do housework at a face pace. Rake leaves or do other yard work.

Some people believe that the only way to increase activity is through rigorous exercise. They think they have to work out in a sweatsuit and perspire profusely to the point of exhaustion. This is not true. It is possible to combat weight gain without torturous exercises. You don't even have to use fancy machines at health clubs or buy heavy weights, especially if you are just beginning. For beginning weight-lifting, you can use household objects like cans of soup or cans of vegetables from your pantry.

Experts recommend that you get aerobic exercise and engage in strength, flexibility, and balance exercises. Aerobic or endurance activities are good for your heart, lungs, circulation, and muscles, and increase your energy levels. Activities to choose from include walking, hiking, dancing, swimming, skating, cycling, and cross-country skiing. Simple walking is one of the best activities to stimulate your circulation, improve the pumping of your heart, and generally make you feel better. If you want a more intense workout while walking, swing your arms back and forth when you walk and lengthen your stride. Some fitness experts call this “pace walking”, or “power walking”.

Flexibility activities help you to move more easily, and allow you to do the daily tasks necessary for long-term independent living and self-reliance. Most people just think of simple stretching when they think of flexibility exercises, but gardening, washing and waxing the car, mopping the floor, vacuuming, and yard work are also flexibility exercises. Golf, yoga, bowling, T'ai Chi, and dancing also enhance flexibility.

Strength and balance activities are activities that challenge all your muscles. They involve pulling, pushing, lifting, and carrying. Lifting weights as light as soup cans can be helpful. Carrying groceries or carrying the laundry count, as does climbing stairs or doing wall push-ups. Remember, start slowly, but do enough to challenge your muscles. If you use weights, use a size that you can lift 10 times before they become too heavy. Don't strain. Remember to breathe naturally, and don't hold your breath. If you have high blood pressure, talk to your family physician before beginning weight training.

To progress further, get advice and help from authorities. Ask your doctor or other health-care providers for suggestions. Look for activity programs at your local community center, a private fitness center, or the YMCA or YWCA. Find out what your active friends do to put activity in their lives. Staying active is an important key to managing your weight.

Drug Therapy

Your doctor is the best source of information on the drug treatment choices available to you.

Other Therapies

A comprehensive behavioral weight control program focusing on eating habits, lifestyle change, and increased exercise is widely considered to be important for overweight and moderately obese individuals. Research indicates that five months of behavioral therapy treatment combined with moderate dietary restriction (1,000 to 1,500 calories per day of self-selected foods) resulted in a mean weight loss of 15 to 20 pounds. Behavioral weight loss programs are also associated with significant decreases in depression and body image dissatisfaction and increases in self-esteem and interpersonal functioning ability.

However, like all treatment programs, these effects were not maintained over time. At a one- year follow-up, patients who received the behavioral treatment with dietary restriction regained 35% to 50% of their weight loss. Five-year follow-ups revealed that the vast majority of patients regained all the weight they had lost.

Surgery

For persons with severe (morbid) obesity (defined as a BMI greater than 40, which means about 100 pounds overweight for men and about 80 pounds for women) and those with less severe obesity but with serious obesity-related complications e.g. diabetes, hypertension and sleep apnea, surgical procedures should be considered. Surgery performed for the purpose of weight loss is called bariatric surgery. Many surgeons in the US perform a variety of bariatric procedures. However, experts who met for a consensus panel discussion in 1993 recommend two surgeries for weight loss: gastric banding (vertical banding gastroplasty), and Roux-en-Y gastric bypass. These two procedures were recommended for weight loss based on their safety tract record and their effectiveness for weight loss.

In gastric banding, a band is placed around the stomach near its upper end, creating a small pouch and a narrow passage into the remainder of the stomach. Both a band and staples are used to create a small stomach pouch. Patients commonly have nausea and vomiting after this procedure, and a good percentage (more than 30%) of patients regained their weight in five years.

In the Roux-en-Y gastric bypass procedure, a small stomach pouch is created by stapling or by vertical banding. Then, a Y-shaped section of the small intestine is attached to the pouch to allow food to bypass the duodenum and the first portion of the jejunum (the first and second portions of the intestine). This causes reduced calorie and nutrient absorption. This surgery causes better weight loss and weight maintenance than gastric banding. Patients who have bypass operations generally lose two-thirds of their excess weight within two years. The weight loss is accompanied by marked improvement in medical complications, as well as in mood, self-esteem, body image, activity levels, and interpersonal and vocational effectiveness. Fewer than 20% of patients will regain their weight in 5 years after the surgery. However, this surgery can cause vitamin B12 and iron deficiencies, as well as calcium malabsorption. People who have this procedure need to take supplements to make up for these deficiencies. As with any major surgery, there are operative risks. In experienced hands, mortality is usually less than 2%, and operative complications are less than 10%.

Alternative Medicine

Most herbal slimming agents have not been tested for safety or effectiveness. Some of those preparations can be dangerous. A few years ago, the British medical journal The Lancet carried a report of a young woman who developed a kidney ailment because she was on a slimming regimen that included Chinese herbs. Follow-up reports from other doctors told of other cases of renal failure and cardiac insufficiency in patients taking capsules with the active ingredient of the herbal preparation.

One remedy that has been tested appears not to work. Researchers from Columbia University's College of Physicians and Surgeons in New York City tested an herb known as Garcinia cambogia as a potential anti-obesity agent. The herb appeared to cause no significant weight loss.

Prognosis

The prognosis for untreated obesity is poor without lifelong behavioral eating and physical activity changes. Research shows that most people gradually regain weight over time no matter what treatment was responsible for their initial weight loss. As a result, some experts have proposed that we abandon traditional weight loss goals based on weight tables in favor of maintaining what some describe as reasonable weight. They point out that significant health benefits are associated with relatively modest weight losses (5% to 10% of excess weight).

Follow-up

Weight control is a lifelong process. Many people who successfully maintain weight loss report that keeping a diet/eating behavior history or diary is often helpful to them in identifying abnormal or unhealthy eating behaviors or patterns. This early warning system allows them time to modify the unhealthy eating behaviors or patterns before they regain all their excess weight.