How We Lose Weight
Your body weight is controlled by the number of calories you eat and the number of calories you use each day. So, to lose weight you need to take in fewer calories than you use. You can do this by becoming more physically active or by eating less. Following a weight-loss program that helps you to become more physically active and decrease the amount of calories that you eat is most likely to lead to successful weight loss. The weight-loss program should also help you keep the weight off by making changes in your physical activity and eating habits that you will be able to follow for the rest of your life.
Types of Weight-Loss Programs
To lose weight and keep it off, you should be aware of the different types of programs available and the important parts of a good program. Knowing this information should help you select or design a weight-loss program that will work for you. The three types of weight-loss programs include: do-it-yourself programs, non-clinical programs, and clinical programs.
Any effort to lose weight by yourself or with a group of like-minded others through support groups, worksite or community-based programs fits in the "do-it-yourself" category. Individuals using a do-it-yourself program rely on their own judgment, group support, and products such as diet books for advice (Note: Not all diet books are reliable sources of weight-loss information).
These programs may or may not be commercially operated, such as through a privately-owned, weight-loss chain. They often use books and pamphlets that are prepared by health-care providers. These programs use counselors (who usually are not health-care providers and may or may not have training) to provide services to you. Some programs require participants to use the program's food or supplements.
This type of program may or may not be commercially owned. Services are provided in a health-care setting, such as a hospital, by licensed health professionals, such as physicians, nurses, dietitians, and/or psychologists. In some clinical programs, a health professional works alone; in others, a group of health professionals works together to provide services to patients. Clinical programs may offer you services such as nutrition education, medical care, behavior change therapy, and physical activity.
Clinical programs may also use other weight-loss methods, such as very low-calorie diets, prescription weight-loss drugs, and surgery, to treat severely overweight patients. These treatments are described below:
Very low-calorie diets
(VLCDs) are commercially prepared formulas that provide no more than 800 calories per day and replace all usual food intake. VLCDs help individuals lose weight more quickly than is usually possible with low-calorie diets. Because VLCDs can cause side effects, obesity experts recommend that only people who are severely overweight use these diets, and only with proper medical care. A fact sheet on VLCDs is available from the Weight-control Information Network (WIN).
Prescribed weight-loss drugs should be used only if you are likely to have health problems caused by your weight. You should not use drugs to improve your appearance. Prescribed weight-loss drugs, when combined with a healthy diet and regular physical activity, may help some obese adults lose weight. However, before these medications can be widely recommended, more research is needed to determine their long-term safety and effectiveness. Whatever the results, prescription weight-loss drugs should be used only as part of an overall program that includes long-term changes in your eating and physical activity habits. A fact sheet on prescription medications for the treatment of obesity is available from WIN.
You may consider gastric surgery to promote weight loss if you are more than 80 pounds overweight. The surgery, sometimes called bariatric surgery, causes weight loss in one of two ways: 1) by limiting the amount of food your stomach can hold by closing off or removing parts of the stomach or 2) by causing food to be poorly digested by bypassing the stomach or part of the intestines. After surgery, patients usually lose weight quickly. While some weight is often regained, many patients are successful in keeping off most of their weight. In some cases, the surgery can lead to problems that require follow-up operations. Surgery may also reduce the amount of vitamins and minerals in your body and cause gallstones. For additional information, a fact sheet on gastric surgery is available from WIN.
If you are considering a weight-loss program and you have medical problems, or if you are severely overweight, programs run by trained health professionals may be best for you. These professionals are more likely to monitor you for possible side effects of weight loss and to talk to your doctor when necessary.
Whether you decide to use the do-it-yourself, non-clinical, or clinical approach, the program should help you lose weight and keep it off by teaching you healthy eating and physical activity habits that you will be able to follow for the rest of your life.
The word "diet" probably brings to mind meals of lettuce and cottage cheese. By definition, "diet" refers to what a person eats or drinks during the course of a day. A diet that limits portions to a very small size or that excludes certain foods entirely to promote weight loss may not be effective over the long term. Rather, you are likely to miss certain foods and find it difficult to follow this type of diet for a long time. Instead, it is often helpful to gradually change the types and amounts of food you eat and maintain these changes for the rest of your life. The ideal diet is one that takes into account your likes and dislikes and includes a wide variety of foods with enough calories and nutrients for good health.
How much you eat and what you eat play a major role in how much you weigh. So, when planning your diet, you should consider: What calorie level is appropriate? Is the diet you are considering nutritionally balanced? Will the diet be practical and easy to follow? Will you be able to maintain this eating plan for the rest of your life? The following information will help you answer these questions.
Low-calorie Diets. Most weight-loss diets provide 1,000 to 1,500 calories per day. However, the number of calories that is right for you depends on your weight and activity level. At these calorie levels, diets are referred to as low-calorie diets. Self-help diet books and clinical and non-clinical weight-loss programs often include low-calorie diet plans.
The calorie level of your diet should allow for a weight loss of no more than 1 pound per week (after the first week or two when weight loss may be more rapid because of initial water loss). If you can estimate how many calories you eat in a day, you can design a diet plan that will help you lose no more than 1 pound per week. You may need to work with a trained health professional, such as a registered dietitian. Or, you can use a standardized low-calorie diet plan with a fixed calorie level.
The selected calorie level, however, may not produce the recommended rate of weight loss, and you may need to eat more or less.
Make sure that your diet contains all the essential nutrients for good health. Using the
Food Guide Pyramid and the Nutrition Facts Label that is found on most processed food products can help you choose a healthful diet. The Pyramid shows you the kinds and amounts of food that you need each day for good health. The Nutrition Facts Label will help you select foods that meet your daily nutritional needs. A healthful diet should include:
Adequate vitamins and minerals. Eating a wide variety of foods from all the food groups on the Food Guide Pyramid will help you get the vitamins and minerals you need. If you eat less than 1,200 calories per day, you may benefit from taking a daily vitamin and mineral supplement.
Adequate protein. The average woman 25 years of age and older should get 50 grams of protein each day, and the average man 25 years of age and older should get 63 grams of protein each day. Adequate protein is important because it prevents muscle tissue from breaking down and repairs all body tissues such as skin and teeth. To get adequate protein in your diet, make sure you eat 2-3 servings (see Figure 2) from the Meat, Poultry, Fish, Dry Beans, Eggs, and Nuts Group on the Food Guide Pyramid every day. These foods are all good sources of protein.
Source: U.S. Department of Agriculture / U.S. Department of Health and Human Services
Note: A range of servings is given for each food group. The smaller number is for people who consume about 1,600 calories a day, such as sedentary women. The larger number is for those who consume about 2,800 calories a day, such as active men.
Adequate carbohydrates. At least 100 grams of carbohydrates per day are needed to prevent fatigue and dangerous fluid imbalances. To make sure you get enough carbohydrates, eat 6-11 servings (see
Figure 2) from the Bread, Cereal, Rice, and Pasta Group on the Food Guide Pyramid every day.
A daily fiber intake of 20 to 30 grams. Adequate fiber helps with proper bowel function. If you were to eat 1 cup of bran cereal, 1/2 cup of carrots, 1/2 cup of kidney beans, a medium-sized pear, and a medium-sized apple together in 1 day, you would get about 30 grams of fiber.
No more than 30 percent of calories, on average, from fat per day, with less than 10 percent of calories from saturated fat (such as fat from meat, butter, and eggs). Limiting fat to these levels reduces your risk for heart disease and may help you lose weight. In addition, you should limit the amount of cholesterol in your diet. Cholesterol is a fat-like substance found in animal products such as meat and eggs. Your diet should include no more than 300 milligrams of cholesterol per day (one egg contains about 215 milligrams of cholesterol, and 3.5 ounces of cooked hamburger contain 100 milligrams of cholesterol).
At least 8 to 10 glasses, 8 ounces each, of water or water-based beverages, per day. You need more water if you exercise a lot.
These nutrients should come from a variety of low-calorie, nutrient-rich foods. One way to get variety -- and with it, an enjoyable and nutritious diet -- is to choose foods each day from the Food Guide Pyramid (see
Types of Diets
Fixed-menu diet. A fixed-menu diet provides a list of all the foods you will eat. This kind of diet can be easy to follow because the foods are selected for you. But, you get very few different food choices which may make the diet boring and hard to follow away from home. In addition, fixed-menu diets do not teach the food selection skills necessary for keeping weight off. If you start with a fixed-menu diet, you should switch eventually to a plan that helps you learn to make meal choices on your own, such as an exchange-type diet.
Exchange-type diet. An exchange-type diet is a meal plan with a set number of servings from each of several food groups. Within each group, foods are about equal in calories and can be interchanged as you wish. For example, the "starch" category could include one slice of bread or 1/2 cup of oatmeal; each is about equal in nutritional value and calories. If your meal plan calls for two starch choices at breakfast, you could choose to eat two slices of bread, or one slice of bread and 1/2 cup of oatmeal. With the exchange-type diet plans, you have more day-to-day variety and you can easily follow the diet away from home. The most important advantage is that exchange-type diet plans teach the food selection skills you need to keep your weight off.
Prepackaged-meal diet. These diets require you to buy prepackaged meals. Such meals may help you learn appropriate portion sizes. However, they can be costly. Before beginning this type of program, find out whether you will need to buy the meals and how much the meals cost. You should also find out whether the program will teach you how to select and prepare food, skills that are needed to sustain weight loss.
Formula diet. Formula diets are weight-loss plans that replace one or more meals with a liquid formula. Most formula diets are balanced diets containing a mix of protein, carbohydrate, and usually a small amount of fat. Formula diets are usually sold as liquid or a powder to be mixed with liquid. Although formula diets are easy to use and do promote short-term weight loss, most people regain the weight as soon as they stop using the formula. In addition, formula diets do not teach you how to make healthy food choices, a necessary skill for keeping your weight off.
Questionable diets. You should avoid any diet that suggests you eat a certain nutrient, food, or combination of foods to promote easy weight loss. Some of these diets may work in the short term because they are low in calories. However, they are often not well balanced and may cause nutrient deficiencies. In addition, they do not teach eating habits that are important for long-term weight management.
Flexible diets. Some programs or books suggest monitoring fat only, calories only, or a combination of the two, with the individual making the choice of both the type and amount of food eaten. This flexible type of approach works well for many people, and teaches them how to control what they eat. One drawback of flexible diets is that some don't consider the total diet. For example, programs that monitor fat only often allow people to take in unlimited amounts of excess calories from sugars, and therefore don't lead to weight loss.
It is important to choose an eating plan that you can live with. The plan should also teach you how to select and prepare healthy foods, as well as how to maintain your new weight. Remember that many people tend to regain lost weight. Eating a healthful and nutritious diet to maintain your new weight, combined with regular physical activity, helps to prevent weight regain.
Regular physical activity is important to help you lose weight and build an overall healthy lifestyle. Physical activity increases the number of calories your body uses and promotes the loss of body fat instead of muscle and other nonfat tissue. Research shows that people who include physical activity in their weight-loss programs are more likely to keep their weight off than people who only change their diet. In addition to promoting weight control, physical activity improves your strength and flexibility, lowers your risk of heart disease, helps control blood pressure and diabetes, can promote a sense of well-being, and can decrease stress.
Any type of physical activity you choose to do -- vigorous activities such as running or aerobic dancing or moderate-intensity activities such as walking or household work -- will increase the number of calories your body uses. The key to successful weight control and improved overall health is making physical activity a part of your daily life.
For the greatest overall health benefits, experts recommend that you do 20 to 30 minutes of vigorous physical activity (see the following Activities Chart) three or more times a week and some type of muscle strengthening activity, such as weight resistance, and stretching at least twice a week. However, if you are unable to do this level of activity, you can improve your health by performing 30 minutes or more of moderate-intensity physical activity (see the Activities Chart) over the course of a day, at least five times a week. When including physical activity in your weight-loss program, you should choose a variety of activities that can be done regularly and are enjoyable for you. Also, if you have not been physically active, you should see your doctor before you start, especially if you are older than 40 years of age, very overweight, or have medical problems. A fact sheet on physical activity and weight control is available from WIN.
Behavior change focuses on learning eating and physical activity behaviors that will help you lose weight and keep it off. The first step is to look at your eating and physical activity habits, thus uncovering behaviors (such as television watching) that lead you to overeat or be inactive. Next you'll need to learn how to change those behaviors.
Getting support from others is a good way to help you maintain your new eating and physical activity habits. Changing your eating and physical activity behaviors increases your chances of losing weight and keeping it off. For additional information on behavior change, you may wish to ask a weight-loss counselor or refer to books on this topic, which are available in local libraries.
What Works for You?
A variety of options exist to help you lose weight and keep it off. The key to successful weight loss is making changes in your eating and physical activity habits that you will be able to maintain for the rest of your life.
No Laughing Matter
Excess weight and physical inactivity
account for more than 300,000 premature deaths each year in the United States,
second only to deaths related to smoking, says the CDC. People who are
overweight or obese are more likely to develop heart disease, stroke, high
blood pressure, diabetes, gallbladder disease, and joint pain caused by excess
uric acid (gout). Excess weight can also cause interrupted breathing during
sleep (sleep apnea) and wearing away of the joints (osteoarthritis).
Carrying extra weight means carrying an
extra risk for certain types of cancer. "[Our] researchers have concluded that
obesity increases the risk for many of the most common cancers worldwide, and
perhaps cancer in general," says Melanie Polk, R.D., director of nutrition
education at the American Institute for Cancer Research (AICR), a nonprofit
research and education organization in Washington, D.C.
In their review of more than 100 studies
and international reports on obesity and cancer risk, completed in October
2001, researchers at the AICR concluded that obesity is consistently linked to
post-menopausal breast cancer, colon cancer, endometrial cancer, prostate
cancer, and kidney cancer.
To address the public health epidemic of
being overweight or obese, former Surgeon General David Satcher issued a "call
to action" in December 2001. The Surgeon General's Call To Action To
Prevent and Decrease Overweight and Obesity outlined strategies that
communities can use in helping to address the problems. Those options included
requiring physical education at all school grades, providing more healthy food
options on school campuses, and providing safe and accessible recreational
facilities for residents of all ages.
Overweight refers to an excess of body weight, but not
necessarily body fat. Obesity means an excessively high proportion of body fat.
Health professionals use a measurement called body mass index (BMI) to classify
an adult's weight as healthy, overweight, or obese (see the BMI chart, "Are You
at a Healthy Weight?"). BMI describes body weight relative to height and is
correlated with total body fat content in most adults.
To get your approximate BMI, multiply
your weight in pounds by 703, then divide the result by your height in inches,
and divide that result by your height in inches a second time.
A BMI from 18.5 up to 25 is considered
in the healthy range, from 25 up to 30 is overweight, and 30 or higher is
obese. Generally, the higher a person's BMI, the greater the risk for health
problems, according to the National Heart, Lung and Blood Institute (NHLBI).
However, there are some exceptions. For example, very muscular people, like
body builders, may have a BMI greater than 25 or even 30, but this reflects
increased muscle rather than fat. "It is excess body fat that leads to the
health problems such as type 2 diabetes, high blood pressure, and high
cholesterol," says Eric Colman, M.D., of the Food and Drug Administration's
Division of Metabolic and Endocrine Drug Products.
In addition to a high BMI, having excess
abdominal body fat is a health risk. Men with a waist of more than 40 inches
around and women with a waist of 35 inches or more are at risk for health
Obesity, once thought by many to be a
moral failing, is now often classified as a disease. The NHLBI calls it a
complex chronic disease involving social, behavioral, cultural, physiological,
metabolic, and genetic factors. Although experts may have different theories on
how and why people become overweight, they generally agree that the key to
losing weight is a simple message: Eat less and move more. Your body needs to
burn more calories than you take in.
A popular weight-loss myth is that
everyone who loses weight eventually gains it back, says Rena Wing, Ph.D., a
professor of psychiatry at Brown Medical School in Providence, R.I. Wing, the
co-developer of a research study known as the National Weight Control Registry,
has worked to deflate this myth.
Tucked away in the registry's database
is information about the weight-control behaviors of more than 3,000 American
adults who have lost an average of 60 pounds and have kept it off for an
average of six years.
How do they do it?
These successful losers report four
common behaviors, says Wing. They eat a low-fat, high-carbohydrate diet, they
monitor themselves by weighing in frequently, they are very physically active,
and they eat breakfast. Eating breakfast every day is contrary to the typical
pattern for the average overweight person who is trying to diet, says Wing.
"They get up in the morning and say 'I'm going to start my diet today,' and
they eat little or no breakfast and a light lunch. Then they get hungry and
consume most of their calories late in the day. Successful weight losers have
managed to change this pattern."
Six years after their weight loss, most
of the registry's successful losers still report eating a low-calorie, low-fat
diet, with about 24 percent of calories from fat. (The Dietary Guidelines for
Americans recommend no more than 30 percent of daily calories from fat.) They
also exercise for about an hour or more a day, expending about 2,800 calories
per week on a variety of activities. This is equivalent to walking 28 miles a
week, or four miles a day, says Wing.
Wing also reports that more than 70
percent of the registry's weight losers became overweight before age
Although Barbara Croft of Columbus,
Ohio, was not an overweight child, she gained weight once she left home and
started cooking for herself. Replacing the plain and simple meals she had as a
child with pizza, sodas, and meat and vegetables laden with sauces, the
5-foot-5-inch Croft worked her way up to 350 pounds. "I always ate from all the
food groups--I just ate huge portions and I ate in between meals," says
When she was diagnosed with type 2
diabetes in February 1999, Croft got scared. "I worried about the health
consequences--about going blind. I already have a little numbness in my
Croft went on a diet and lost 200 pounds
in 19 months. She has kept it off for a year and a half. "This is the third
time I've lost over 100 pounds," says the 52-year-old, 150-pound Croft, "but
this is the longest I've been able to keep the weight off." In her two previous
weight losses, Croft ate nutritious meals, but didn't exercise. This time, she
started walking for exercise, but could only walk about a block at first. "My
husband went with me because he was afraid I wouldn't make it," she says. Now,
Croft walks on a treadmill for 50 minutes a day--25 minutes each morning and
She still eats balanced meals, but
restricts her portions. And she always eats breakfast. "I have Egg Beaters, two
pieces of low-calorie bread, fruit, decaf coffee, and 8 ounces of water." Croft
dines out almost every night, typically eating half her dinner of grilled
chicken or salmon and a vegetable or salad. She sends the other half back, so
she isn't tempted to overeat.
"Losing the weight was easy--maintaining
it is much harder," says Croft.
Croft had tried commercial weight-loss
programs in the past, but this last time she did it on her own. "You have to
find out what works for you," she says. "If I eat butter or cheese, that seems
to do me in. Beef is also a problem."
Croft's diabetes is under control now
without medication. And she says her knees don't hurt anymore, she can buy
clothes in a regular store, and she started traveling again now that she can
fit into an airplane seat.
Setting a Goal
The first step to weight loss is setting
a realistic goal. By using a BMI chart and consulting with your health-care
provider, you can determine what is a healthy weight for you.
Studies show that you can improve your
health with just a small amount of weight loss. "We know that physical activity
in combination with reduced calorie consumption can lead to the 5 to 10 percent
weight loss necessary to achieve remission of the obesity-associated
complications," says William Dietz, M.D., Ph.D., director of the Division of
Nutrition and Physical Activity at the CDC. "Even these moderate weight losses
can improve blood pressure and help control diabetes and high cholesterol in
obese or overweight adults."
To reach your goal safely, plan to lose
weight gradually. A weight loss of one-half to 2 pounds a week is usually safe,
according to the Dietary Guidelines for Americans. This can be achieved by
decreasing the calories eaten or increasing the calories used by 250 to 1,000
calories per day, depending on current calorie intake. (Some people with
serious health problems due to obesity may lose weight more rapidly under a
doctor's supervision.) If you plan to lose more than 15 to 20 pounds, have any
health problems, or take medication on a regular basis, a doctor should
evaluate you before you begin a weight-loss program.
Changing Eating Habits
Dieting may conjure up visions of eating
little but lettuce and sprouts--but you can enjoy all foods as part of a
healthy diet as long as you don't overdo it on fat (especially saturated fat),
protein, sugars, and alcohol. To be successful at losing weight, you need to
change your lifestyle--not just go on a diet, experts say.
Limit portion sizes, especially of foods
high in calories, such as cookies, cakes and other sweets; french fries; and
fats, oils and spreads. Reducing dietary fat alone--without reducing
calories--will not produce weight loss, according to the NHLBI's guidelines on
treating overweight and obesity in adults.
Use the Food Guide
Pyramid, developed by the U.S. Department of Agriculture (USDA) and the
Department of Health and Human Services, to help you choose a healthful
assortment of foods that includes vegetables, fruits, grains (especially whole
grains), fat-free milk, and fish, lean meat, poultry, or beans. Choose foods
naturally high in fiber, such as fruits, vegetables, legumes (such as beans and
lentils), and whole grains. The high fiber content of many of these foods may
help you to feel full with fewer calories.
All calorie sources are not created
equal. Carbohydrate and protein have about 4 calories per gram, but fat has
more than twice that amount (9 calories per gram). Just as for the general
population, weight-conscious consumers should aim for a daily fat intake of no
more than 30 percent of total calories.
Keep your intake of saturated fat at
less than 10 percent of calories. Saturated fats increase the risk for heart
disease by raising blood cholesterol. Foods high in saturated fats include
high-fat dairy products (like cheese, whole milk, cream, butter, and regular
ice cream), fatty fresh and processed meats, the skin and fat of poultry, lard,
palm oil, and coconut oil.
If you drink alcoholic beverages, do so
in moderation. Alcoholic beverages supply calories but few nutrients. A
12-ounce regular beer contains about 150 calories, a 5-ounce glass of wine
about 100 calories, and 1.5 ounces of 80-proof distilled spirits about 100
Limit your use of beverages and foods
that are high in added sugars--those added to foods in processing or
preparation, not the naturally occurring sugars in foods such as fruit or milk.
Foods containing added sugars provide calories, but may have few vitamins and
minerals. In the United States, the major sources of added sugars include
non-diet soft drinks, sweets and candies, cakes and cookies, and fruit drinks
Using the Food Label
Under regulations from the FDA and the
USDA, the food label, found on almost all processed foods, offers more
complete, useful and accurate nutrition information than ever before. Even when
restricting calories and portions, you can use the part of the food label
called the Nutrition Facts
panel to make sure you get all the essential nutrients for good
You'll find the serving size and the
number of servings per package listed at the top of the Nutrition Facts panel.
The serving size affects all the nutrient amounts listed on the panel. For
example, if there is one cup in a serving and the package contains two
servings, you need to double the calories and other nutrient numbers if you eat
the whole package. Many items sold as single portions--like a 20-ounce soft
drink, a 3-ounce bag of chips, and a large bagel--actually provide two or more
"If you zero in on the 'amount per
serving' section of the Nutrition Facts panel, you can tell at a glance how
many calories a serving has and whether a food is high in total fat, saturated
fat, cholesterol, and sodium," says Naomi Kulakow, coordinator of food labeling
education in the FDA's Center for Food Safety and Applied Nutrition. "These are
items you should think about limiting in your diet."
The Nutrition Facts panel also shows how
much dietary fiber, vitamin A, vitamin C, calcium, and iron are contained in a
serving. These are nutrients you need for good health.
Also listed on the Nutrition Facts panel
are the amounts of carbohydrates, protein, and sugars contained in a serving.
Use the panel to compare the amount of total sugars among similar products, and
try to choose ones lower in sugars.
In addition to listing some nutrients by
weight, the panel also gives this information as a Percent Daily Value (%DV).
The %DV shows how a serving of a food fits in with recommendations for a
healthful diet and allows consumers to make comparisons between similar
For example, shoppers can use the %DV
figures to find out which frozen dinner is lower in saturated fat--particularly
when it involves a comparative nutritional claim, such as reduced-fat. "You
don't need to know the precise definition of 'low' or 'reduced,'" says Kulakow.
"Just look at the Percent Daily Value and see which is higher or lower in the
nutrient you are interested in." Foods with 5 percent or less of the Daily
Value are considered low in a nutrient, while those with 20 percent or more are
high in the nutrient.
The %DVs are based on a 2,000-calorie
daily diet. But even if you eat less than 2,000 calories, the %DV can be used
to determine whether a food is high or low in a particular nutrient.
"People use the food label too often to
just restrict calories and fat--not to get enough nutrients," says Kulakow.
While restricting calories is important for weight loss, "most people have no
idea how many calories they consume every day--especially if they eat out." The %DV gives you a frame of reference and can be used to make dietary trade-offs,
says Kulakow. "For example, if you eat a favorite food that's high in fat at
one meal, balance it with low-fat foods at other times of the day."
caution when choosing foods that are labeled "fat-free" and "low-fat." Fat-free
doesn't mean calorie-free. To make a food tastier, sometimes extra sugars are
added, which adds calories (see "Fat-Free vs.
Regular Calorie Comparison"). So dieters should always check the Nutrition
Facts panel to get complete information, says Kulakow.
Most health experts recommend a
combination of a reduced-calorie diet and increased physical activity for
weight loss. Most adults should get at least 30 minutes and children should get
60 minutes of moderate physical activity on most, and preferably all, days of
the week. But fewer than 1 in 3 U.S. adults gets the recommended amount of
physical activity, according to The Surgeon General's Call To Action To
Prevent and Decrease Overweight and Obesity.
In addition to helping to control
weight, physical activity decreases the risk of dying from coronary heart
disease and reduces the risk of developing diabetes, hypertension, and colon
cancer. Researchers also have found that daily physical activity may help a
person lose weight by partially lessening the slow-down in metabolism that
occurs during weight loss.
Exercise does not have to be strenuous
to be beneficial. And some studies show that short sessions of exercise several
times a day are just as effective at burning calories and improving health as
one long session.
To lose weight and to maintain a healthy
weight after weight loss, many adults will likely need to do more than 30
minutes of moderate physical activity daily.
For obese people who have difficulty
losing weight through diet and exercise alone, there are a number of
FDA-approved prescription drugs that may help. "On average, individuals who use
weight-loss drugs lose about 5 percent to 10 percent of their original weight,
though some will lose less and some more," says the FDA's Colman.
All of the prescription weight-loss
drugs work by suppressing the appetite except for Xenical (orlistat). Approved
by the FDA in 1999, Xenical is the first in a new class of anti-obesity drugs
known as lipase inhibitors. Lipase is the enzyme that breaks down dietary fat
for use by the body. Xenical interferes with lipase function, decreasing
dietary fat absorption by 30 percent. Because the undigested fats are not
absorbed, fewer calories are available to the body. This may help in
controlling weight. The main side effects of Xenical are cramping, diarrhea,
flatulence, intestinal discomfort, and leakage of oily stool.
Meridia (sibutramine), approved by the
FDA in 1997, increases the levels of certain brain chemicals that help reduce
appetite. Because it may increase blood pressure and heart rate, Meridia should
not be used by people with uncontrolled high blood pressure, a history of heart
disease, congestive heart failure, irregular heartbeat, or stroke. Other common
side effects of Meridia include headache, dry mouth, constipation and
Other anti-obesity prescription drugs
that were approved by the FDA many years ago based on very short-term, limited
data include: Bontril (phendimetrazine tartrate), Desoxyn (methamphetamine) and
Ionamin and Adipex-P (phentermine). They are "speed"-like drugs that should not
be used by people with heart disease, high blood pressure, an overactive
thyroid gland, or glaucoma. These drugs are approved only for short-term use,
such as a few weeks. They generally don't cause weight loss beyond several
weeks, and they have significant potential for physical dependence or
"There is no magic pill for obesity,"
says David Orloff, M.D., director of the FDA's Division of Metabolic and
Endocrine Drug Products. "The best effect you're going to get is with a
concerted long-term regimen of diet and exercise. If you choose to take a drug
along with this effort, it may provide additional help."
Until September 1997, two other drugs,
fenfluramine (Pondimin and others) and dexfenfluramine (Redux), were available
for treating obesity. But at the FDA's request, the manufacturers of these
drugs voluntarily withdrew them from the market after newer findings suggested
that they were the likely cause of heart valve problems. The FDA recommended
that people taking the drugs stop and that they contact their doctor to discuss
Prescription weight-loss drugs are
approved only for those with a BMI of 30 and above, or 27 and above if they
have other risk factors, such as high blood pressure or diabetes.
People should contact a doctor before
using any kind of drug, including a weight-loss drug.
Over-the-counter (OTC) weight-control
drugs contain the active ingredient phenylpropanolamine, which is also used as
a nasal decongestant. The FDA recently asked drug manufacturers to discontinue
marketing products containing phenylpropanolamine, based on evidence linking
the substance to an increased risk of hemorrhagic stroke (bleeding in the
brain). In addition, the FDA issued a public health advisory in November 2000,
warning consumers to stop using products containing this ingredient.
The FDA is proposing to classify
phenylpropanolamine as "not generally recognized as safe," and is proceeding
with regulatory actions that will likely remove this ingredient from the
Beware of Unproven Claims
Some dietary supplement makers claim
their products work for weight loss. These products are not reviewed by the FDA
before they are marketed. "Under our existing laws, manufacturers have the
responsibility for ensuring that their dietary supplement products are safe and
effective," says Christine Lewis Taylor, Ph.D., R.D., director of the FDA's
Office of Nutritional Products, Labeling, and Dietary Supplements.
Many weight-loss products claim to be
"natural" or "herbal," but this does not necessarily mean that they're safe.
These ingredients may interact with drugs or may be dangerous for people with
certain medical conditions. If you are unsure about a product's claims or the
safety of any weight-loss product, check with your doctor before using it.
Worth the Effort
"Losing weight requires major lifestyle
changes, including diet and nutrition, exercise, behavior modification,
and--when appropriate--intervention with drug therapy," says Judith S. Stern, Sc.D., professor of nutrition and internal medicine at the University of
California, Davis, and vice president of the American Obesity Association. "But
it is always worth making the effort to improve your health."
Linda Bren is a staff writer
for FDA Consumer.
Avoid 'Fad' Diets
The cabbage soup diet, the
low-carbohydrate and high-protein diet, and other so-called "fad" diets are
fundamentally different from federal nutrition dietary guidelines and are not
recommended for losing weight.
Fad diets usually overemphasize one
particular food or type of food, contradicting the guidelines for good
nutrition, which recommend eating a variety of foods from the Food Guide
Pyramid. These diets may work at first because they cut calories, but they
rarely have a permanent effect.
A high-protein diet is one fad diet that
has remained popular over the years. "High-protein items may also be high in
fat," says Robert Eckel, M.D., professor of medicine at the University of
Colorado Health Sciences Center in Denver. High-fat diets can raise blood
cholesterol levels, which increases a person's risk for heart disease and
High-protein diets force the kidneys to
try to get rid of the excess waste products of protein and fat, called ketones.
A buildup of ketones in the blood (called ketosis) can cause the body to
produce high levels of uric acid, which is a risk factor for gout (a painful
swelling of the joints) and kidney stones. Ketosis can be especially risky for
people with diabetes because it can speed the progression of diabetic renal
disease, says Eckel.
"It's important for the public to
understand that no scientific evidence supports the claim that high-protein
diets enable people to maintain their initial weight loss," says Eckel. "In
general, quick weight-loss diets don't work for most people."
Tips for Eating Out
- Choose foods that are steamed,
broiled, baked, roasted, poached or stir-fried.
- Share food, such as a main dish or
dessert, with your dining partner.
- Take part of the food home with you,
and refrigerate immediately. You may want to ask for a take-home container when
the meal arrives. Spoon half the meal into it, so you're more likely to eat
only what's left on your plate.
- Request your meal to be served
without gravy, sauces, butter or margarine.
- Ask for salad dressing on the side,
and use only small amounts of full-fat dressings.