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Weight Loss - Ways to Win!
Americans trying to lose weight have plenty of company. According
to a 1995 report from the Institute of Medicine (IOM), tens of millions
of Americans are dieting at any given time, spending more than $33
billion yearly on weight-reduction products, such as diet foods
and drinks.
Yet, studies over the last two decades by the National Center for
Health Statistics show that obesity in the United States is actually
on the rise. Today, approximately 35 percent of women and 31 percent
of men age 20 and older are considered obese, up from approximately
30 percent and 25 percent, respectively, in 1980.
The words obesity and overweight are generally used interchangeably.
However, according to the IOM report, their technical meanings are
not identical. Overweight refers to an excess of body weight that
includes all tissues, such as fat, bone and muscle. Obesity refers
specifically to an excess of body fat. It is possible to be overweight
without being obese, as in the case of a body builder who has a
substantial amount of muscle mass.
It is possible to be obese without being overweight, as in the
case of a very sedentary person who is within the desirable weight
range but who nevertheless has an excess of body fat. However, most
overweight people are also obese and vice versa. Men with more than
25 percent and women with more than 30 percent body fat are considered
obese.
Many people who diet fail to lose weight--or, if they do lose,
fail to maintain the lower weight over the long term. As the IOM
report, "Weighing The Options: Criteria for Evaluating Weight-Management
Programs," points out, obesity is "a complex, multifactorial
disease of appetite regulation and energy metabolism."
Because many factors affect how much or how little food a person
eats and how that food is metabolized, or processed, by the body,
losing weight is not simple. For example, recent studies suggest
a role for genetic makeup in obesity. This area is still controversial,
and more studies will be needed before scientists can say with certainty
that a person's genes may set limits on how much weight can be lost
and maintained.
Yet many people persist in seeking simple cures to this complex
health problem. Lured by fad diets or pills that promise a quick
and easy path to thinness, they end up disappointed when they regain
lost weight.
No Shortcuts
"There are no shortcuts--no magic pills," says Lori Love,
M.D., Ph.D., of the Food and Drug Administration's Center for Food
Safety and Applied Nutrition. Losing weight sensibly and safely
requires a multifaceted approach that includes setting reasonable
weight-loss goals, changing eating habits, and getting adequate
exercise. Appetite suppressants (diet pills) or other products may
help some people over the short term, but they are not a substitute
for adopting healthful eating habits over the long term.
The first step in losing weight safely is to determine a realistic
weight goal.
A physician, dietitian or nutritionist also can help you set a
reasonable goal. To reach the goal safely, plan to lose 1 to 2 pounds
weekly by consuming approximately 300 to 500 fewer calories daily
than usual (women and inactive men generally need to consume approximately
2,000 calories to maintain weight; men and very active women may
consume up to 2,500 calories daily).
Moderation, Variety and Balance
After determining a reasonable goal weight, devise an eating plan
based on the cornerstones of healthful eating--moderation, variety
and balance, suggests Victor Herbert, M.D., J.D., professor of medicine
and director of the Nutrition Center at the Mount Sinai School of
Medicine and Bronx VA Medical Centers in New York City, and member
of the board of directors of the National Council Against Health
Fraud.
"Moderation means not eating too much or too little of any
particular food or nutrient; variety means eating as wide a variety
as possible from each, and within each, of the five basic food groups;
and balance refers to the balance achieved by following moderation
and variety, as well as the balance of calories consumed versus
calories expended," he explains. To lose weight, fewer calories
should be consumed than expended; to maintain weight loss, the number
of calories consumed and expended should be about the same.
Because fat is the most concentrated source of calories (9 calories
per gram compared to 4 calories per gram for carbohydrate and protein),
it is usually the focus of weight-maintenance and weight-loss diets.
Limiting fat intake alone will likely limit calories, as well. Just
as for the general population, weight-conscious consumers should
limit fat intake to no more than 30 percent of total calories, according
to the Dietary Guidelines for Americans.
Alcoholic beverages also are a source of calories (7 per gram of
alcohol). Twelve ounces of regular beer, for example, provides 150
calories; the same amount of "light" beer, 105 calories.
Five ounces of wine or 1.5 ounces of 80-proof distilled spirits
provide 100 calories. But alcohol provides few, if any, nutrients,
so if you drink alcoholic beverages and want to reduce your weight,
consider reducing or eliminating your alcohol intake.
In selecting your diet, follow the five basic food groups and the
recommended number of servings from each as incorporated into the
Food Guide Pyramid developed by USDA and HHS. These groups are (1)
bread, cereal, pasta, and rice; (2) vegetables; (3) fruits; (4)
milk, yogurt and cheese; and (5) meat, poultry, fish, dry beans,
eggs, and nuts. A sixth group (fats, oils and sweets) consists mainly
of items that are pleasing to the palate but high in fat and/or
calories; these should be eaten in moderation.
Avoid low-calorie fad diets that exclude whole categories of food
such as carbohydrates (bread and pasta) or proteins (meat and poultry).
These diets may be harmful because they generally do not include
all nutrients necessary for good health. "Every fad diet that
demands an unusual eating pattern, such as emphasizing only a few
types of foods, deviates from one or more of the guidelines of moderation,
variety and balance," says Herbert. "The greater the deviation,
the more harmful the diet is likely to be."
Using the Food Label
To help consumers plan a healthful diet, FDA and USDA have revamped
food labels. By law, most food labels now must display a Nutrition
Facts panel containing information about how the food can fit into
an overall daily diet. Nutrition Facts state how much saturated
fat, cholesterol, fiber, and certain nutrients are contained in
each serving.
On the food label, %Daily Value shows what percentage of a given
nutrient is provided in one portion for daily diets of 2,000 calories.
Whether or not a given food fits into a weight-loss diet depends
on what other foods you eat that day. For most people, the goal
is to select a variety of foods that together add up to approximately
100 percent of the Daily Value for total carbohydrate, dietary fiber,
vitamins, and minerals; total fat, cholesterol and sodium each may
add up to less than 100 percent.
Foods that claim to contain fewer calories or less fat than similar
servings of similar products must show the difference on the label.
For example, on a container of low-fat cottage cheese, the label
would show that a serving of the low-fat product contains 80 calories
and 1.5 grams of fat while regular cottage cheese contains 120 calories
and 5 grams of fat per serving.
Camille Brewer, a registered dietitian and nutritionist in FDA's
Center for Food Safety and Applied Nutrition, advises caution, however,
when choosing foods that are labeled "fat-free" and "low-fat."
Some of these foods, like "low-fat" cakes and cookies,
still may be high in calories because of added sugars. So dieters
should always check the Nutrition Facts panel to get complete information,
she says.
Look for foods high in fiber, such as fruits, vegetables, legumes
and whole grains. Fiber can be an important aid in weight maintenance
because eating enough of it can help make a person feel full and
thus not eat as much.
To see how the new label can help you stick to your diet, see Dieters'
Label Checklist (a 119K PDF file)
Exercise
Regular exercise is important for overall health, as well as for
losing and maintaining weight. There is evidence to suggest that
body fat distribution affects health risks. For example, excess
fat in the abdominal area (as opposed to hips and thighs) is associated
with greater risk for high blood pressure, diabetes, early heart
disease, and certain types of cancer. Vigorous exercise can reduce
abdominal fat and thus lower the risk of these diseases.
The Dietary Guidelines for Americans recommends a half hour or
more of moderate physical activity on most days, preferably every
day. The activity can include brisk walking, calisthenics, home
care, gardening, moderate sports exercise, and dancing. Regular
exercise can help the body use up calories consumed daily, as well
as excess calories stored as fat. Weight-bearing exercises also
help tone muscles and may reduce the risk of osteoporosis.
OTC Diet Pills
The 1991/1992 Weight Loss Practices Survey, sponsored by FDA and
the National Heart, Lung, and Blood Institute, found that 5 percent
of women and 2 percent of men trying to lose weight use diet pills.
Products considered by FDA to be over-the-counter weight control
drugs are primarily those containing the active ingredient phenylpropanolamine
(PPA), such as Dexatrim and Acutrim. PPA is available OTC for weight
control in a 75-mg controlled-release dosage form. The medicine
should be used in combination with a restricted diet and exercise.
Using diet pills containing PPA will not make a big difference
in the rate of weight loss, says Robert Sherman of FDA's Office
of OTC Drug Evaluation. "Even the best studies show only about
a half pound greater weight loss per week using PPA combined with
diet and exercise," he adds. Sherman cautions that the recommended
dosage of these pills should not be exceeded because of the risk
of possible adverse effects, such as elevated blood pressure and
heart palpitations.
Since PPA is also used as a nasal decongestant in over-the-counter
cough and cold products, consumers should read the labels of OTC
decongestants to see if they contain PPA. They should not take PPA
in two products labeled for different uses.
Sherman notes that FDA has received a small number of reports indicating
that PPA use might be associated with an increased risk of stroke.
A large-scale safety study was begun in September 1994 to explore
the possibility. Based on available data, the agency does not believe
that an increased risk of stroke is a concern when PPA is used at
recommended dosages.
Rx Drugs
FDA has approved several prescription drugs for obesity. The newest
is Xenical (orlistat), which FDA approved in April 1999.
Xenical is the first in a new class of anti-obesity drugs known
as lipase inhibitors. Lipase is the enzyme that breaks down fat
for use by the body. Xenical interferes with lipase function, decreasing
fat absorption by 30 percent. Since undigested fats are not absorbed,
there is less calorie intake, which may have a positive effect on
weight control.
Other approved anti-obesity prescription drugs available on
the market include:
- Dexedrine and other amphetamines
- Ionamin and Adipex-P (phentermine)
- Sanorex (mazindol)
- Tenuate (diethylpropion)
- Prelu-2 (phendimetrazine) and other amphetamine derivatives
- Meridia (sibutramine).
In mostly short-term studies of obese adults following a calorie-restricted
diet, those who took the appetite suppressants lost more weight
on average than those who took a placebo. The amount of weight lost
varied from study to study.
FDA approved the drugs only for use with calorie-restricted diets.
The drugs are "not magic pills," warns Leo Lutwak, M.D.,
Ph.D., of FDA's division of metabolism and endocrine drug products.
"They don't work unless you make dietary and exercise changes."
Also, they should be used only for a few weeks partly because,
aside from Xenical, the drugs are addictive and have the potential
for abuse. They shouldn't be used in combination with each other
or with other drugs for appetite control because such combinations
have not been evaluated for safety. And the drugs should be used
only in people who are obese--not people looking to lose a few pounds,
Lutwak says.
"Weight-loss drugs are serious medicine for a serious disease,"
he says.
Also, he points out that while obesity may be associated with other
serious diseases, studies have never shown that weight loss produced
with the use of prescription weight-loss drugs benefits obesity-associated
conditions. However, changes in diet and activity may improve associated
diseases, such as diabetes and high blood pressure, even with only
modest changes in weight, Lutwak says.
Until September 1997, two other drugs, fenfluramine (Pondimin and
others) and dexfenfluramine (Redux), were available for treating
obesity. But, at 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 in a large
proportion of people using them. FDA recommended that anyone taking
the drugs stop and that they contact their doctor to discuss their
treatment. (Check the latest information on this topic on FDA's
Website.)
Weight-Loss Programs
Many people turn to weight-loss programs for help in planning a
daily diet and changing lifestyle habits. The IOM report provides
guidelines for evaluating the potential effectiveness of such programs.
"To improve their chances for success, consumers should choose
programs that focus on long-term weight management; provide instruction
in healthful eating, increasing activity, and improving self-esteem;
and explain thoroughly the potential health risks from weight loss,"
according to the report. Consumers should also demand evidence of
success. If it is absent or consists primarily of testimonials or
other anecdotal evidence, "the program should be viewed with
suspicion."
IOM recommends that potential clients be given a truthful, unambiguous,
non-misleading statement about the program's approaches and goals,
and a full disclosure of costs. The cost breakdown should include
initial and ongoing costs, as well as the cost of extra products.
The basic tenet of weight loss--to eat fewer calories than you
burn and to stay active--is easy to say but, like most lifestyle
changes, not so easy to do. With realistic goals, and a commitment
to losing weight slowly, safely and sensibly, the chances of long-term
success improve dramatically. n
by Marilynn Larkin

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