Losing Weight: More Than Counting Calories
By Linda Bren
Americans are getting fatter. We're putting on the pounds
at an alarmingly rapid rate. And we're sacrificing our health for
the sake of supersize portions, biggie drinks, and two-for-one value
meals, obesity researchers say.
More than 60 percent of U.S. adults are either overweight
or obese, according to the Centers for Disease Control and Prevention
(CDC). While the number of overweight people has been slowly climbing
since the 1980s, the number of obese adults has nearly doubled since
then.
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.
Are You Overweight?
link to long descriptionOverweight 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. (Or you
can use the interactive BMI calculator at www.nhlbisupport.com/bmi/bmicalc.htm.)
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
problems.
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.
Successful 'Losers'
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 18.
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 Croft.
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 feet."
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 night.
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.
link to larger picture of Food Guide Pyramid[D]
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 calories.
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 and fruitades.
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 health.
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 servings.
"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 products.
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."
Kulakow advises 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.
For further guidance on using the Nutrition Facts panel,
visit FDA's Center for Food Safety and Applied Nutrition.
Increasing Physical Activity
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.
Prescription Weight-Loss Drugs
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 insomnia.
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 addiction.
"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 their treatment. (For the
latest information on this topic, visit www.fda.gov/cder/news/feninfo.htm.)
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 Drugs
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 market.
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 certain cancers.
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."
--L.B.
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.
--L.B