Medically Reviewed by Amanda G. Powell, MD
Assistant Professor of Medicine
Department of Endocrinology, Diabetes and Nutrition and Weight Management
Boston University School of Medicine
- Overview & Diagnosis
- Treatment & Prevention
- Facts to Know & Questions to Ask
- Key Q&A
- Organizations and Support
What Is It?
Obesity is a complex disorder. It is caused by multiple factors, both environmental and inherited, including excessive calorie and food intake, decreased physical activity and genetic influences.
America has become a country with a rapidly expanding population of overweight people. Today approximately 68.3 percent of American adults are either overweight or obese, and 33.9 percent are obese, according to the Centers for Disease Control and Prevention (CDC). The obesity epidemic is a rapidly growing problem in this country. In 2000, no state had an obesity prevalence of 30 percent or more. In 2009, nine states had obesity rates of 30 percent or more. And by 2010, the number of states that had obesity rates of 30 percent or more increased to 12. Why are these facts alarming?
Obesity, defined as a body mass index (BMI) of 30 or more, is the second leading cause of preventable death in the United States and results in an estimated $147 billion in health care costs each year.
Overweight individuals, defined as having a BMI between 25 and 29.9, are more likely to have high blood pressure and high blood cholesterol, major risk factors for heart disease and stroke. Additionally, the results of a large study supported by the U.S. National Heart, Lung, and Blood Institute (NHLBI) suggest that excess body weight is strongly and independently associated with an increased risk of heart failure.
Overweight and obesity also are major risk factors for developing type 2 diabetes. Diabetes is a major cause of early death, heart disease, kidney disease, stroke, blindness and amputation.
Several types of cancer are associated with being overweight, including cancer of the uterus, gallbladder, kidney, breast and colon. Other conditions linked with obesity include sleep apnea, osteoarthritis, gout, gallbladder disease and infertility. Obesity-related conditions worsen as weight increases and often improve as the excess weight is lost.
Obesity is a major component of a group of metabolic risk factors known collectively as metabolic syndrome, which is defined as having at least three of the following five markers:
- A waist measurement of more than 35 inches in women and more than 40 inches in men
- A fasting blood glucose level of 100 mg/dL or higher; or you're already taking medication because you have high blood glucose levels.
- A triglyceride level at or above 150 mg/dL. Triglycerides are a form of fat in your blood.
- An HDL cholesterol level (the "good" cholesterol) below 50 mg/dL (below 40 mg/dL in men); or you're already taking medication to increase your HDL level.
- Blood pressure at or above 130 mm Hg systolic (the top number) or 85 mm Hg diastolic (the bottom number); or you're already taking medication to treat high blood pressure.
Health conditions that promote metabolic syndrome are overweight/obesity, physical inactivity and genetic factors. People who have this syndrome are at increased risk for developing coronary heart disease, stroke, peripheral arterial disease and type 2 diabetes.
Obesity is a complex disorder. It is caused by multiple factors, both environmental and inherited, including excessive calorie and food intake, decreased physical activity and genetic influences. Though there may be other factors that affect weight gain, such as genetic and environmental influences, you most likely gain weight because you consume more calories (energy) than your body uses or needs.
What's the difference between being obese and being overweight? The defining characteristic in both overweight and obese people is excess body fat. The difference is a matter of degree.
Health care professionals use a simple calculation called the body mass index (BMI) to determine body weight relative to height. In adults, the BMI calculation strongly correlates with total body fat content in adults. Overweight is defined as having a body mass index (BMI) between 25 and 29.9. Obesity is defined as having a BMI of 30 or more. Use to check your BMI. Another way to determine your risk relative to your weight is to measure your waist circumference. Women with a waist circumference over 35 inches (and men over 40 inches) are at greater risk for disease.
Where excess body fat is distributed on your body also plays a role in your risk for disease. Weight gain around your waist (specifically in your abdominal area) is more of a health risk than weight gained on your hips and thighs. Unlike fat around the thighs, which is more common in women and is more likely to serve as an energy reservoir, abdominal fat deposits fatty acids directly into the bloodstream for immediate short-term energy, increasing triglyceride and, eventually, cholesterol levels. Therefore, excess abdominal fat is associated with an increase in blood cholesterol and insulin resistance, which may result in diabetes. An "apple shaped" figure may also raise your risks for other life-threatening illnesses, such as heart disease and stroke.
An excess of body fat—the defining characteristic of obesity—results from an imbalance between the amount of calories you take in and those you expend. The reasons for this imbalance are unclear, and the relationship between energy intake/expenditure and body fat storage and distribution varies from person to person. Factors that promote obesity include:
family history of obesity
behavioral factors (including a high-fat or high-calorie diet and sedentary lifestyle)
Assessing your weight to determine if you are obese involves two key measurements—body mass index (BMI) and waist circumference. Understanding your risk factors for conditions associated with obesity, according to clinical practice guidelines issued by the National Heart, Lung, and Blood Institute (NHLBI), is important. First, your health care professional should determine your body mass index (BMI), which describes your body weight relative to your height. It is strongly correlated with total body fat content in adults. Your BMI is your weight in pounds divided by your height in inches squared, then multiplied by 703. The following chart shows body mass indices for people of various heights and weights. To determine your BMI, find the row that most closely approximates your weight. Read across the row until it crosses the column closest to your height. You may also use .
A woman or man with a BMI between 25 and 29.9 is considered overweight; 30 or more is considered obese; and 40 or greater is considered extreme obesity. Women in the highest obesity category have a significantly higher risk of hypertension and/or high blood cholesterol than women of normal weight.
In addition to comparing your weight to a chart of established acceptable weight ranges, your health care professional can actually measure your body composition—the most accurate assessment technique because it differentiates between weight that is attributable to fat accumulation and weight that represents muscle development. Women with more than 30 percent body fat (25 percent for men) are considered obese. However, it is difficult to measure body fat precisely. The most accurate method has been to weigh a person underwater, but this procedure is limited to laboratories with special equipment. Your health care professional is more likely to conduct one or more of these tests:
Measuring skin-fold thickness and subcutaneous fat, which lie just under the skin, at targeted areas. These areas include the back of your upper arm, waist or thigh. The health care professional uses calipers, an instrument that looks like tongs. Measurements of skin-fold thickness depend on the skill of the examiner and may vary widely
Bioelectrical impedance analysis (BIA). There are two forms of BIA. With one form, the patient stands on a special scale with footpads and a harmless amount of electrical current is sent through her body to calculate the percentage body fat. The second type of BIA involves the use of a portable instrument called an impedance analyzer to transmit a noninvasive, low frequency electrical current through electrodes placed on the patient's hand and foot with a gel. The change in voltage between electrodes is measured, and the patient's body fat percentage is calculated.
Waist circumference. Unlike fat around the thighs, which is more common in women and is more likely to serve as an energy reservoir, abdominal fat delivers fatty acids directly into the bloodstream for immediate short-term energy, increasing triglyceride and, eventually, cholesterol levels. Health care professionals aren't certain why this proves detrimental to your health, but higher proportions of abdominal fat are associated with higher risks of insulin resistance, diabetes, high blood pressure and cardiovascular disease (heart disease and stroke).
How can you estimate your body fat distribution? Look at yourself in the mirror. If you are more apple-shaped than pear-shaped, you probably have visceral fat accumulation. Women with a waist circumference over 35 inches (and men over 40 inches) are at greater risk.
Your health care professional also should ask you about or conduct tests to determine other risk factors for disease and conditions associated with obesity. This includes:
Taking a personal weight history
Determining your waist-to-hip ratio. Divide your waist measurement by your hip measurement (the widest part of your behind). Ideally, women should have a waist-to-hip ratio of 0.8 or less.
Asking if you have relatives with illnesses related to being overweight, such as type 2 diabetes mellitus or heart disease
Discussion of weight-loss methods used in the past
Taking your blood pressure and conducting blood tests such as measuring your cholesterol and screening for diabetes
It is important to tell your health care professional about any medical or health conditions you have and any medications, vitamins, minerals, herbs or nutritional supplements you're taking. Also let your health care professional know if you are pregnant or breast-feeding or if you're planning on surgery that requires general anesthesia.
The types of health care professionals you might consult to diagnose and treat obesity include:
A nutritionist. There is no accepted national definition for the title "nutritionist." Some states have a statutory definition of nutritionist stating that the RD credential is not required for certification as a nutritionist but is required for licensing as a dietitian. In general, the license or certification as a dietitian can be obtained with a bachelor's degree and a related supervised practice experience component (or proof of RD status with the Commission on Dietetic Registration), while the nutritionist licensure or certification typically requires a master's degree or higher.
Make sure any nutritionist you see is licensed by a state agency. Nutritionists, with educational background in foods and nutrition, and dietitians evaluate the diets and nutritional habits of clients and help structure more healthful eating patterns and weight-management strategies based on their patients' health needs, food selection and calorie goals. Nutritionists usually do not advise patients with chronic illnesses, disorders and other disease conditions.
A registered dietitian (RD). An RD is a dietitian who has completed academic and practice requirements established by the American Dietetic Association. These include a bachelor's degree, an accredited preprofessional experience program, successful completion of a national credentialing exam and ongoing continuing professional development. Many RDs also have a master's degree and advanced training in a nutrition subspecialty, such as diabetes.
An endocrinologist. Endocrinology is the field of medicine involving the body's chemical messengers, or hormones, and its biochemical control mechanisms, or metabolism. Endocrinologists are physicians who care for patients with complex hormonal disorders and metabolic conditions, including obesity, diabetes, thyroid disorders, metabolic bone disease, pituitary and adrenal conditions, and growth and gonadal disorders.
- An obesity medicine specialist. These physicians have specific training and clinical expertise in managing obesity and the related medical problems.
Losing as little as 5 percent to 10 percent of your body weight and maintaining that loss can significantly improve your health by increasing glucose tolerance and lowering blood pressure and cholesterol levels. Thus, if you're overweight or obese, you may need to seek medical help to lose weight as well as to maintain it.
Experts recommend losing no more than one to two pounds per week. Maintaining weight loss can be more difficult than losing the weight to begin with, so long-term lifestyle change is key.
The National Weight Control Registry is tracking over 10,000 individuals who have lost significant amounts of weight and kept it off for extended periods of time. Members of the registry have lost an average of 66 pounds and kept the weight off for an average of 5.5 years. The individuals who are listed in the registry have reported the following:
90 percent exercise, on average, about 60 minutes per day.
45 percent of registry participants lost the weight on their own, and the other 55 percent lost weight with the help of some type of program.
78 percent eat breakfast every day.
62 percent watch less than 10 hours of TV per week.
NWCR members kept the weight off in various ways. Most report continuing to maintain a low-calorie, low-fat diet and engaging in high levels of activity.
Other key habits of people who successfully maintain their weight loss include weighing themselves routinely and writing down their daily food intake in a journal or tracking it with an online application.
The good news is that burning off more calories than you're taking in will cause you to lose weight. The bad news is that there's no magic formula. Studies find that if you lose the weight slowly, you'll be much more effective at keeping it off, especially if you incorporate exercise into your routine and reduce other sedentary behavior, such as watching TV.
The safest way to lose weight is to eat a nutritionally complete diet that is moderate in calories and fat, add exercise to your daily routine and decrease sedentary activities. In some cases, for example, if your health is being immediately and severely compromised because of your weight, faster weight loss may be appropriate. In these cases, your health care professional may recommend drug therapy or surgery.
Changing Your Diet
The first element of treatment is changing your diet. Your health care professional should provide detailed guidance on the number and types of calories you should eat. As a rule of thumb, however, if you take in about 250 calories per day less than is needed to maintain your current weight, combined with an exercise regime that burns an additional 250 calories a day, you'll lose about a pound a week.
The number of calories your body needs to maintain its basic functions such as breathing and digestion is known as your basal metabolic rate (BMR). Several factors go into the calculation of your BMR, including your age, height, weight and gender. To get an idea of your BMR, go to .
It's difficult to determine exactly how many calories you need to maintain your weight at your current level of physical activity. One way to estimate your BMR is to keep a detailed food diary over the course of a few days to a week during which you maintain your weight. Determine exactly how many calories you eat on an average day (several books and Web sites provide calorie counts for thousands of foods) and use that figure as a starting place from which you then subtract 250 calories.
After you've determined how many calories a day you should eat, you need to plan daily menus. A dietitian or nutritionist can help you plan menus that include the types and amounts of food you should eat, which, in most cases, should be based on guidelines developed by the federal government in its 2010 Dietary Guidelines for Americans. The guidelines emphasize calorie reduction as well as balance, moderation and variety in food choices, with an emphasis on whole-grain products, vegetables and fruits.
To satisfy basic nutritional needs, eat a variety of foods including low-fat dairy, healthy protein sources like chicken, fish, eggs and soy products, vegetables and whole grains, and allow for an occasional treat. While you should try to cut back on excess fats and sugars, all foods and beverages can be consumed in moderation. As soon as you label a food as "off limits," chances are you will crave and perhaps even binge on it.
The 2010 Dietary Guidelines recommend the following (based on a 2,000 calorie-per-day diet). These are general guidelines from the U.S. Department of Agriculture and the U.S. Department of Health and Human Services. The amount you personally need will vary based on many factors, including your age, weight, activity level and personal medical history, so be sure to discuss your diet with your health care professional.
Meat and beans (protein)
Eat five-and-a-half ounces of protein every day (vary your choices of meats, poultry, fish, beans, peas, nuts and seeds). Try to include at least 8 ounces of seafood per week. Generally, the guidelines recommend 10 percent to 35 percent of your daily calories come from protein. Another way of looking at it is you should eat at least 1 gram of protein per kilogram of body weight. If you weigh 70 kilograms (approximately 154 pounds), you should aim to eat about 70 to 100 grams of protein per day.
Fruits, vegetables and dairy
Eat two cups a day of fruit and two-and-a-half cups a day of vegetables.
Eat a variety of fruits and vegetables every day and choose from all of the five vegetable subgroups (dark green, orange, legumes, starchy vegetables and other vegetables) several times per week. You may consume fresh, frozen, canned or dried; go light on fruit juices.
Consume the equivalent of three cups per day of dairy products, including yogurt, cheese, milk or calcium-fortified soy beverages. Most choices should be fat-free or low-fat.
Eat six ounces of grains (cereal, breads, crackers, rice or pasta) a day. At least three ounces should be whole grain, and the other three enriched or whole grain. One ounce equals about one slice of bread, one cup of cereal or one-half cup of cooked rice, cereal or pasta.
Eat fruits and vegetables that are high in fiber and choose whole grains.
Try to avoid adding sugar or sweeteners to foods and beverages.
Sodium and potassium
Do not consume more than 2,300 mg of sodium (approximately 1 teaspoon of salt) per day. Individuals who are 51 years old or older and those of any age who are African American or have hypertension, diabetes or chronic kidney disease should lower their intake to 1,500 mg per day. Talk to your health care professional about what's best for you, because recommendations can vary based on your health history, medications, genetics and other factors.
Use little or no salt when preparing foods.
Eat fruits and vegetables high in potassium such as potatoes, sweet potatoes, soybeans, bananas and spinach. (There are some people who should not consume high-potassium foods, such as those who take certain blood pressure medications, so be sure and talk to your doctor.)
Balanced food plans encourage making wise choices about everyday foods so you can maintain a healthy weight throughout your lifetime. Many popular diet plans, however, such as the high-protein/low-carbohydrate diet, don't include balanced choices. While women can lose weight on these diets, they may find themselves dangerously deficient in certain nutrients or food groups and dangerously high in others. In most cases, women who go on these diets tend to regain any lost weight when the diet ends. That's because these diets don't help you change your lifestyle and your way of handling food and temptation in the long run.
Most successful weight-loss plans call for a reduction in both calories and fat. Overall, managing caloric intake and increasing physical activity are most important.
Many health care professionals and dietary guidelines recommend women moderate their fat consumption to 20 percent to 35 percent or less of total calorie intake, with saturated fats accounting for less than 10 percent and the rest comprised of equal amounts of monounsaturated fat and polyunsaturated fats. These fats come from vegetable, not animal, sources.
Also, reduce your cholesterol intake to less than 300 mg per day. Strategies for reducing saturated fat and cholesterol include:
Only eat three servings or less per week of red meats, processed meats, organ meats, eggs and high-fat dairy products.
Choose low saturated-fat protein sources, such as fish, turkey, chicken, legumes (dried peas and beans), nuts and seeds.
Use lean cuts of meat and trim excess fat.
Substitute skim and low-fat milk and other dairy products for high-fat dairy foods.
Broil, bake or boil foods instead of frying.
Increase your consumption of fruits, vegetables and whole grains.
In addition to low-fat dietary approaches, some large studies point to the Mediterranean-style diet as an alternative pattern of eating to reduce your risk of heart disease. Like the low-fat diets, the Mediterranean eating pattern focuses on fruits, vegetables, whole grains, nuts and seeds, but it also includes substituting olive oil (a monounsaturated fat) for saturated fats and drinking wine in low to moderate amounts. The major protein sources are dairy, fish and poultry, with minimal red meat.
The Mediterranean eating style allows a somewhat higher percentage of calories from fat than the low-fat diets typically endorsed by health organizations. Several recent major studies have shown that the diet is an alternative to low-fat diets, especially for lowering risk of diabetes and heart attacks, often related to weight.
Increasing Physical Activity
The second element to losing weight and maintaining a healthy weight is adding exercise to your daily routine and reducing the time you spend sitting. Exercise not only burns calories, it also tempers your appetite, boosts metabolism, improves sleep and provides psychological benefits, such as stress reduction and an increased feeling of control and self-esteem.
If you have been inactive for some time, suffer from shortness of breath or weakness that interferes with daily activities or have a chronic health condition such as heart disease, asthma or lung disease, diabetes, liver or kidney disease or arthritis, consult a health care professional before increasing your physical activity. If you're a woman older than 55 and are overweight or are concerned about your family history or personal health history, talk with your health care professional before starting to exercise. Notify him or her about any chest pain, faintness or dizziness, bone or joint pain you're experiencing, and any medications you're taking.
Physical activity is defined as any bodily movement produced by skeletal muscles resulting in energy expenditure. The best kinds of exercises for burning calories are moderate- to vigorous-intensity physical activities. The calories burned per hour are listed for a 140-pound healthy woman.
Moderate-intensity activities include:
hiking (386 calories)
light gardening/yard work (302 calories)
dancing (319 calories)
golf, walking and carrying the clubs (244 calories)
bicycling, less than 10mph (370 calories)
walking, 3.5 mph (370 calories)
yoga (336 calories)
Vigorous-intensity physical activities include:
aerobics, high-impact (445 calories)
calisthenics (512 calories)
running/jogging, 5 mph (580 calories)
swimming (580 calories)
bicycling, 12 to 14 mph (554 calories)
racquetball, casual (445 calories)
skiing, downhill (554 calories)
weight lifting, vigorous (400 calories)
While you and your health care professional should set up a detailed exercise plan based on your individual health status, the 2010 Dietary Guidelines recommend healthy women who want to manage body weight and prevent gradual unhealthy weight gain engage in 150 minutes (2 hours, 30 minutes) a week of moderate-intensity or 75 minutes (1 hour, 15 minutes) of vigorous-intensity aerobic activity or an equivalent combination of moderate- and vigorous-intensity aerobic activity. If you want to reap additional and more extensive health benefits, you should engage in moderate-intensity aerobic activity for 300 minutes (5 hours) or vigorous-intensity activity for 150 minutes per week. The guidelines also recommend that adults perform muscle-strengthening activities that involve all major muscle groups at least two days a week.
You don't have to do all 150 minutes at once; if possible, aerobic activity should be spread throughout each week and can be divided up throughout the day. For example, 30 minutes of an aerobics video in the morning and 30 minutes of brisk walking in the evening works just as well as walking for an hour straight. If you have been inactive, you need to work up slowly to this amount so you don't get injured or overly fatigued and become discouraged. Start with five or 10 minutes (or whatever you're comfortable with) every other day, adding one minute every other session.
Low- to moderate-intensity exercise, like housework, gardening and walking the dog, provide a great deal of general health benefits, but for weight loss, you need to up the ante and exercise at a higher intensity with more vigorous activities like brisk walking or jogging, singles tennis or other racquet sports, aerobics classes, ice or roller skating, swimming or cycling.
The best way to keep weight off once it's been lost is with an average of 60 to 90 minutes of moderate-intensity exercise per day, most days a week, while being careful not to exceed your specific daily calorie requirement.
Because the goal of moderate to vigorous exercise is to work your heart muscle, your exercise needs to increase your heart rate. One way to determine if you are exercising intensely enough is to measure your heart rate. After warming up and then sustaining an aerobic activity for about five to 10 minutes, take your pulse within five seconds of stopping by placing two fingers on the carotid artery on the side of your neck, just under your jaw line and about one to two inches in front of your ear. Count the beats for 10 seconds. Multiply this number by six to determine the heart rate in beats per minute. Your heart rate should be about 50 to 85 percent of its maximum. (You can calculate your maximum heart rate by subtracting your age from 220).
If you're out of shape or older than 60, aim for an intensity at the lower end of the 50 percent to 85 percent range. To determine what your heart rate should be during exercise, subtract your age from 220; divide that number by six for a 10-second heart rate count, then multiply that number by 0.5 for the lower end of the range and 0.85 for the higher end. For example, if you're 70:
220 - 70 = 150 (this would be your maximum heart rate for one minute)
150 / 6 = 25 (this would be your maximum heart rate for 10 seconds)
25 x 0.50 = 12.5 (this would be 50 percent of your maximum, or the lower end of where your 10-second heart rate should be when you're exercising)
25 x 0.85 = 21.25 (this would be 85 percent of your maximum, or the higher end of where your 10-second heart rate should be when you're exercising).
The following chart illustrates recommended 10-second heart rate counts; the number of beats you count should fall between the two numbers listed beside your age.
|(Age)||70 % of maximum||85 % of maximum|
An easier way to judge intensity is the "talk test." You shouldn't be exercising so hard that you can't talk with a friend or recite a poem. If you can't talk without gasping for breath, slow down. On the other hand, if your exercise is easy enough that you can sing a song out loud, you probably need to increase your intensity.
Another type of exercise has received much attention over the past several years for its contribution to weight loss efforts. Strength training, which includes weight lifting and isometrics, or using your own body weight as resistance, not only improves muscular strength and endurance but raises metabolism, enabling you to burn more calories.
Make sure you take a few minutes to stretch and warm up before doing any kind of exercise.
It's best to incorporate a combination of both types of exercise into your lifestyle—moderate to vigorous physical activities to burn fat and strength training to build muscle. Neither is as effective alone.
At the same time, you need to reduce the amount of television you watch, since TV watching is independently associated with obesity.
Medications for Treating Obesity
Women with increased medical risk from their obesity may benefit from adding a weight-loss medication to their nutritional/exercise regimen.
Most research-based and professional associations recommend lifestyle therapy for at least six months before embarking on a weight-loss plan using physician-prescribed drug therapy. Even then, it must be used only as part of a comprehensive weight loss program that includes dietary therapy and physical activity. Currently available prescription medications include:
phentermine (Adipex-P, Ionamin, Oby-Cap, T-Diet, Zantryl)
phentermine topirmate (Qsymia)
Lorcaserin is the newest drug available. It was approved by the FDA in 2012 and is expected to be available in the United States starting in early 2013. In clinical trials, the drug was twice as effective as a placebo in helping people lose 5 percent or more of their weight. The most common side effects are headaches, nausea and dizziness, but it also can cause neuropsychiatric and cognitive problems.
Orlistat also is now available over the counter under the brand name Alli in 60-milligram pills, half the strength of the prescription dosage in Xenical. It is the first FDA-approved over-the-counter weight loss drug. Like Xenical, Alli blocks digestion of about 25 percent of the fat eaten at a meal. Orlistat has been found to be safe and effective in combination with a low-fat (less than 30 percent fat), low-calorie diet, though it can cause significant gastrointestinal side effects, especially when you start using it. In clinical trials, people taking the drug lost 4.4 to 6.6 pounds more over a year than those not taking the drug.
Phentermine is a widely prescribed appetite suppressant. It is often prescribed to help control portions and manage hunger.
Qsymia, which combines phentermine and topiramate (a drug also used to prevent migraines and treat epilepsy), is a newly approved weight loss drug that produces weight loss via complementary mechanisms and allows for the use of each agent at a lower dose. This potentially minimizes side effects and maximizes weight loss benefits. Data has shown that people who take the highest dose of Qsymia can achieve up to a 10.5 percent weight loss after two years of treatment. As with all medications, the risks and benefits of treatment need to be evaluated by your health care provider. Certain people are not good candidates for treatment, including those with uncontrolled high blood pressure, cardiac disease or unstable psychiatric disease.
If you are pregnant or plan to become pregnant, talk to your health care provider about using Qsymia or any medications.
If you are considering taking drugs for weight loss, remember: NEVER take a drug or herb that hasn't been prescribed or recommended by your health care professional. There are numerous potentially dangerous over-the-counter drugs and herbs that claim to help you lose weight, but, except for Alli, they have not been approved by the FDA and may cause significant health complications and even death.
For clinically severe obesity, your health care provider may recommend surgery. Many people, including some health care professionals, wrongly believe that obese people merely need to stop eating so much to lose weight. In reality, extreme obesity is a potentially deadly disease that sometimes requires a treatment as dramatic as surgery. Surgery is an option for carefully selected patients under the care of a health care professional. Most physicians consider people for the surgery who:
have tried other methods of weight loss (changes in eating behavior, increased physical activity and/or drug therapy) and are still severely obese
have a BMI of at least 40 (or 35 in addition to other medical conditions such as diabetes, hypertension high cholesterol and/or obstructive sleep apnea)
understand the procedure, risks of surgery and long-term lifestyle changes required
are motivated to make a lifelong behavioral commitment that includes well-balanced eating and physical activity needed to achieve—and maintain—desired results
There are several types of bariatric surgery:
Roux-en-Y gastric bypass (RYGB). In this procedure, the stomach is reduced to the size of a golf ball. The stomach is divided into a large portion and a small portion. The small portion is sewn or stapled together to make a small pouch, which holds only about a cup of food. The small pouch is then disconnected from the upper portion of the digestive tract and reconnected to a lower portion of the intestine. Not only do you eat fewer calories, but your body absorbs fewer calories because part of the intestine, the duodenum, has been bypassed. There is a risk of nutrition deficiencies, and you will need lifelong monitoring.
Laparoscopic adjustable gastric banding (LAGB). This procedure is performed laparoscopically, through a small incision in the abdomen. The surgeon wraps an inflatable band around the top of the stomach, which separates the stomach into two parts, with a very small upper part that communicates with the stomach through a channel formed by the band. The band can be inflated and deflated to restrict more or less food. You eat less because you feel full sooner. Because it is a relatively simple procedure, LAGB is one of the more common weight loss surgeries. However, it may result in less weight loss than other procedures, and the band may require periodic readjustment.
Other less common procedures include:
Biliopancreatic bypass with duodenal switch (BPDS). In this procedure, much of the stomach is removed, leaving only a "gastric sleeve" that is attached to the small intestine, completely bypassing the duodenum and upper small intestine. In a similar procedure, called biliopancreatic diversion with duodenal switch, a smaller portion of the stomach is removed, and the remaining stomach (gastric sleeve) remains attached to the duodenum. The duodenum is connected to the lower part of the small intestine. As with the gastric bypass procedure, you absorb fewer calories with both of these procedures. You also eat less because your stomach is so much smaller. Removing part of the stomach is also thought to reduce production of an appetite-related hormone called grehlin. This procedure is very effective, but it comes with serious risks, including vitamin deficiencies and malnutrition. Therefore, it is usually used for people with a BMI over 50.
Sleeve gastrectomy. Also called vertical sleeve gastrectomy, sleeve gastrectomy is a newer type of weight-loss surgery. It is the first part of the surgery performed in the BPDS. This procedure is performed when first part of BPDS surgery is all that's necessary for sufficient weight loss. With sleeve gastrectomy, the structure of the stomach is changed to the shape of a tube, so it restricts the amount of calories the body absorbs.
- Vertical banded gastroplasty. Also called "stomach stapling," this procedure divides the stomach into two parts, which restricts the amount of food that can be eaten. The smaller upper pouch empties into the larger lower pouch—the rest of your stomach. This procedure generally doesn't lead to adequate long-term weight loss, so it isn't used as often as other procedures.
All procedures can lead to "full and rapid" remission of diabetes, sleep apnea, hypertension, kidney failure and other weight-related medical conditions.
While bariatric surgery is extremely safe, the greatest risks come after the surgery. Some occur soon after the operation, such as hemorrhage, obstruction, infection, hernias, pulmonary embolisms (blood clots in the lung) and leaks between the areas where tissue was sewn together.
Long-term complications include nutritional deficiencies, including malabsorption of vitamin B12, iron, thiamine and calcium; and hypoglycemia, or low blood sugar, which can lead to various medical conditions, including neuropathy.
The average person undergoing bariatric surgery loses about 60 percent to 80 percent of excess body weight. That means if you weigh 250 pounds and your "ideal" body weight is 150 pounds, you have an "excess" of 100 pounds. On average, you may lose 60 80 pounds after surgery, putting you at a weight of about 170 to 190 pounds after the procedure.
After surgery, you have to learn to eat smaller amounts of food at one time, to chew food well and to eat slowly. If you don't adjust your eating habits, you won't lose as much weight. Additionally, especially in the first three months after surgery, you must be sure to eat the proper amounts of protein, calories, minerals and vitamins as recommended by your health care professional, and you will likely need nutritional supplements for the rest of your life.
Another key to successful weight loss is incorporating behavioral strategies into your new eating and exercise activities. These include learning about nutrition, planning what to eat and making sure you eat regularly to end impulsive and thoughtless eating.
Some specific and helpful behavioral strategies include:
Set the right goals. Your goals should focus on specific dietary and exercise changes, such as "I will eat five servings of fruits and vegetables every day this week," or, "I will work up to being able to walk briskly for 30 minutes at a time," rather than just on weight loss. Select two or three goals at a time to incorporate into your lifestyle rather than trying to change everything at once. Effective goals are specific, attainable and forgiving, which means that you don't have to be absolutely perfect. Remember, too, in setting your goals, that losing more than one to two pounds per week can be unhealthy and greatly increases the chances of regaining the weight.
Reward success. To encourage yourself to attain your goals, reward yourself for successes. An effective reward is something that is desirable and timely such as attending the cinema or taking an hour for yourself. Don't use food as a reward!
Keep a food and exercise diary. Many behavioral psychologists believe it's necessary to track your daily food consumption to achieve long-term weight loss. From a simple pad of paper to a computerized program that provides reports and analyses of your progress, the best tool is the one you use every day. Incorporate your goals, such as eating five servings of fruits or vegetables each day, into your self-monitoring efforts.
Monitor your weight sensibly. Keep track of your weight, but don't weigh too often. One day's diet and exercise patterns won't have a measurable effect on the scale the next day, and your body's water weight can change from day to day, which may frustrate you and derail your efforts.
Join a support group. Weekly meetings at a nearby support group or even over the Internet can help in a variety of ways. They provide accountability, helpful ideas, emotional support, an outlet for sharing frustrations and a variety of other psychological benefits.
Use positive self-talk. Take responsibility and see yourself as in control, able to talk yourself into exercising every day rather than being angry, hopeless or in denial.
Find ways other than food to respond to stress and other situations in your life. Certain cues, from stress to watching television, may stimulate unhealthy eating. In some cases, you can avoid those cues; don't go to that Mexican restaurant where you always eat too many chips, for example. For situations that can't be avoided, however, such as the business lunch or an argument with your spouse, learn new ways to respond. If you track the situations surrounding your overeating in your food diary, you can more easily determine the cues you need to be aware of.
Change the way you go about eating. There are a variety of tricks—from using a smaller plate to eating more slowly—that can help you eat less. Setting an eating schedule, starting meals with a broth-based soup, only buying foods on a pre-planned menu, using a meal replacement once or twice a day and other similar efforts can all help.
When eating out, don't feel compelled to finish your entire meal if portion sizes are too large. The steady growth of food portion sizes served both in restaurants and at home has encouraged the overeating that is fueling the obesity epidemic in the United States, according to a survey by the American Institute for Cancer Research.
Appropriate portion size is very important. When dining out, for instance, try to take home at least half of your dish. Share your entrée with a friend or ask your waiter to put half of the portion in a to-go box before it is served to you. When eating at home, serve your plate and leave the remaining food in the kitchen; do not place it on the table. Half of your plate should be filled with vegetables and fruits, one quarter with a protein and one quarter with grains, preferably whole grains. Never, ever, supersize any kind of fast food or take-out meal.
Health care professionals and researchers stress that if you are obese, losing as little as 5 percent to 10 percent of your body weight can improve or prevent many of the health problems linked to your condition, such as high blood pressure and diabetes.
Facts to Know
The rate of obesity in the United States has risen from 12 percent in 1991 to 33.9 percent today. One reason: Americans are eating more calories than they did 30 years ago.
Another contributing factor to obesity: Less than half of Americans exercise regularly, and at least 25 percent are not active at all.
Obesity is the second leading cause of preventable death in the United States and contributes to $147 billion a year in health care costs. The Centers for Disease Control and Prevention reports that 33.9 percent of American women 20 years of age and older are obese.
One measure of obesity is your body mass index (BMI). You can calculate your BMI by going .
If a woman's BMI is 30 or greater, she is considered obese. A BMI of 40 or more puts her in the extremely obese category. However, if she has more muscle mass than normal, these numbers won't apply, and her health care professional should measure her body composition to determine her degree of overweight.
If a woman's waist circumference is more than 35 inches, she is considered to have a high amount of visceral fat, which is the type of fat that surrounds the internal organs. This type of fat is associated with higher risk of certain diseases and conditions like diabetes and heart disease.
If you eat 250 calories per day fewer than needed to maintain your weight and exercise enough to burn an additional 250 calories a day, you will lose about a pound per week.
Overweight people are at an increased risk for numerous serious health problems, including diabetes, high blood cholesterol, high blood pressure and increased risk of heart attack, stroke and heart failure. Luckily, losing as little as 5 percent to 10 percent of your body weight can improve or prevent many of these conditions.
Surgical treatment of obesity involves, a reduction in the size of your stomach, limiting the amount of food it can hold. Physicians typically consider it only for patients who have tried other weight loss methods and are still severely obese. Most people undergoing bariatric surgery are able to lose a significant amount of weight, but they must commit to changing their eating habits and will likely need nutritional supplements for life.
The current U.S. Dietary Guidelines recommend that women who want to manage body weight and prevent unhealthy weight gain engage in 150 minutes (2 hours, 30 minutes) a week of moderate-intensity, or 75 minutes (1 hour, 15 minutes) of vigorous-intensity aerobic activity or an equivalent combination of moderate- and vigorous-intensity aerobic activity. For additional and more extensive healthy benefits, the guidelines recommend 300 minutes (5 hours) of moderate-intensity or 150 minutes of vigorous-intensity aerobic activity per week, or an equivalent combination of moderate- and vigorous-activity. You should perform aerobic exercise in episodes of at least 10 minutes, and preferably, it should be spread throughout the week. The guidelines also recommend that adults perform muscle-strengthening activities that involve all major muscle groups at least two days a week.
Questions to Ask
Review the following Questions to Ask about obesity so you're prepared to discuss this important health issue with your health care professional.
Have my body composition and risk factors—as well as my height and weight—been considered in your diagnosis?
Based on my current weight, how many calories a day should I eat to achieve my goal?
Based on my fitness level, how much and what types of exercise would be best for me to start with?
Do I need to undergo an electrocardiogram or other type of test before beginning an exercise program? What is my resting heart rate? What should my heart rate be while I'm exercising? What signals should I watch for while I'm exercising that could tell me I'm overdoing it?
Can you recommend a registered dietitian to help me achieve my weight loss goals?
How will I be evaluated to determine if I am an appropriate candidate for weight-loss medications?
Am I a candidate for bariatric surgery? Why or why not?
What are the complications or possible side effects of any type of diets, medication, surgery or other treatment you are recommending? What symptoms should I watch for?
What kind of program will help me maintain my weight loss?
What's the difference between being overweight versus obese?
In both overweight and obese people, the defining characteristic is excess body fat. The difference is a matter of degree. Overweight people usually have a body mass index (BMI), or ratio of weight to height, of 25 to 29.9. Obesity is usually defined as a BMI of 30 or more. Another measure of obesity is having more than 30 percent body fat. While overweight people have a higher incidence of certain diseases and conditions than normal weight individuals, as people gain weight, they become even more prone to these often life-threatening problems.
I'm more than 20 percent overweight, but I'm happy and satisfied with my life, so why should I care about my weight?
Being overweight or obese is bad for your health, even if you're only slightly overweight. Excess weight is a major risk factor for heart disease and stroke and is linked to a higher incidence of diabetes, which you are twice as likely to develop as a person of normal weight. In addition, it is associated with several types of cancers, gout, gallbladder disease and other diseases.
According to the charts, I'm categorized as obese, but I don't look fat, and I exercise at least five times a week, doing both aerobic exercises and weight training. What's going on?
Chances are you are one of the individuals who don't fit neatly into the BMI or height/weight charts because you have a significant amount of muscle, which is denser—and therefore, heavier—than fat and makes your weight seem above the normal limits. What's more important to consider is your body composition—your proportion of fat to muscle. As an avid exerciser and weight lifter, it's doubtful your body fat is greater than 30 percent, but if you are truly concerned, you can ask your health care professional to do a body composition test.
At 240 pounds, I have more than 80 pounds to lose. I feel like I'll never achieve that. Should I just give up?
Don't give up. Losing as little as 5 percent to 10 percent of your body weight—in your case, 12 to 24 pounds—can significantly improve your health. Health care professionals recommend that your first effort at losing weight should be at this level, followed by a period of maintenance before trying to lose more.
I realize I need to lose weight. How should I start?
The safest way to lose weight is, in most cases, to eat a nutritionally complete diet that cuts about 250 calories a day from the number of calories your body requires to maintain its present weight, add an exercise regime that burns an additional 250 calories a day. If you do this, you will lose about a pound a week.
All of these moderate-intensity activities will burn at least 250 calories per hour for a 140-pound, healthy woman:
- hiking (386 calories)
- light gardening/yard work (302 calories)
- dancing (319 calories)
- bicycling, less than 10 mph (370 calories)
- tennis, singles (386 calories)
- walking, 3.5 mph (370 calories)
- yoga (336 calories)
More vigorous activities, such as calisthenics, running, swimming, downhill skiing and high-speed bicycling, will burn 500 or more calories per hour.
Do I have to exercise?
You don't have to exercise, but it is extremely beneficial. Not only will exercise make the weight come off more quickly and easily, it will make your weight loss much easier to maintain. Regular physical activity also can help reduce your risk of certain health problems.
I've heard some nightmare stories about stomach stapling and other obesity-related surgical procedures. Are they safe?
For clinically severe obesity, bariatric surgery is safer than remaining severely obese. Because there are various types of operative procedures, you should speak with your health care professional about the specific safety statistics of the ones that might be best for you. In addition, consistent follow-up and patient compliance with post-surgical treatment is crucial to the success of these surgeries. These surgical procedures are used only in patients who have been unsuccessful at losing weight in other ways.
Organizations and Support
American Council on Exercise
Address: 4851 Paramount Drive
San Diego, California 92123
Address: P.O. Box 44020
Rio Rancho, NM 87174
Shape Up America!
Address: 15009 Native Dancer Road
North Potomac, MD 20878
Staying Fit on Campus
Affordable Colleges Resource Center
Medline Plus: Weight Control
Address: Customer Service
8600 Rockville Pike
Bethesda, MD 20894
Email: [email protected]
Teens Health from Nemours