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LOSING WEIGHT: WHAT WORKS. WHAT DOESN'T.
In the first large-scale survey of the major weight-loss
programs, we found that no program is very effective. Here's why
diets usually don't work, and how you can manage your weight more
wisely.
Fifty million Americans are dieting at any given time, and these
days, most of them are thoroughly confused. After decades in
which medical authorities, the fashion industry, and most
ordinary people agreed that the pursuit of thinness was an
unmitigated good, the wisdom of dieting has come into question.
Researchers have found that yo-yo dieting, the common cycle of
repeatedly losing and regaining weight, may be as bad for you as
weighing too much in the first place. Sobered by that research --
and by the realization that many dieters become yo-yo dieters --
members of a growing antidiet movement have urged people to throw
away their calorie counters and eat whenever they're hungry.
Despite those developments, it is still possible and worthwhile
for some people to lose weight. But a review of the scientific
literature, interviews with experts in the field, and CU's own
research show that a major shift in thinking about weight loss is
in order. For the typical American dieter, the benefits of weight
loss are no longer certain -- and the difficulty of losing weight
permanently has become all too clear.
Medical researchers have suspected for years that most diets end
in failure; studies done at weight-loss clinics in medical
centers showed that people almost always regained the weight they
lost. But it was never clear whether people at those clinics had
an unusually poor success rate because they were "hard cases" who
needed special help.
Now CU has undertaken the first large-scale survey of people on
ordinary diet programs and shown that they, too, usually fail at
losing weight in the long term. We collected information from
95,000 readers who had done something to lose weight over the
previous three years, including some 19,000 who had used a
commercial diet program. As we report [on page 353], our survey
showed that people do lose weight on these programs -- but the
great majority of them gain back most of that weight within two
years.
Although different weight-loss programs use different diets and
strategies, none have been able to overcome this basic pattern.
The problem is that losing weight is much more than a matter of
willpower: It's a process that pits the dieter against his or her
own physiology.
Why people get fat
A small number of people have struggled with obesity since
childhood and are massively overweight as adults. A greater
number are not overweight when they enter adulthood, but become
so as they gain 10, 20, or 30 pounds over the course of two or
three decades. And about three-quarters of American adults are
not overweight at all.
What makes for the difference? Primarily, it's the genes. An
individual's body size, studies have conclusively shown, is
genetically coded as surely as the shape of a nose. Inheritance
overwhelms other factors in determining an individual's normal
range of weight, which may be relatively high for one person, low
for another. While diet and exercise certainly play a role, they
do so within limits set by heredity.
Over and over again, researchers have observed the human body's
remarkable resistance to major weight change. Dr. Rudolph Leibel,
an obesity researcher at Rockefeller University in New York City,
describes how extremely obese people repeatedly enter the
university's weight-loss clinic, lose dozens of pounds, go home,
and return six months later having regained precisely the amount
of weight they lost. Other clinicians have reported similar, if
less dramatic, results.
What's less widely known is that the body resists major weight
*gain* as much as it resists a major loss. In a classic study
conducted in the 1960s by Dr. Ethan Allen Sims of the University
of Vermont, a group of 20 prisoners of normal weight volunteered
to gain as much weight as possible. Only by forcing themselves to
overeat -- some by thousands of calories a day -- were the men
able to add 20 percent to their weight and keep it on. Once the
study ended, almost everyone returned quickly to his starting
weight.
No one knows just how the body keeps weight within a fairly
narrow range; researchers posit the existence of some sort of
biochemical control system, but they haven't found it. Whatever
the mechanism is, however, it allows weight to drift slowly
upward as people get older. Two major changes take place with
age. People tend to become less physically active. and, partly as
a result of inactivity, people lose lean muscle mass, which burns
calories more rapidly than fatty tissue.
No wonder, then, that the prime time for dieting is the mid-40s.
"That's when people start to look fat or study a height-weight
table and say to themselves, `Gee, I've crossed over a line,'"
says David Williamson, an epidemiologist who studies weight
patterns for the Centers for Disease Control and Prevention.
Weight and health
Even if some people are genetically programmed to be fatter than
others, their natural body size may not necessarily be a health
one. Researchers are now struggling with a difficult question: At
what point do the risks of overweight make the effort to lose
weight worthwhile?
To begin to answer that question, scientist have used a measure
called the body mass index, or BMI, which incorporates both
height and weight to assess a person's level of fatness. You can
find your own BMI by following the instructions [in the second
note after this one]. Scientists consider a BMI of 25 or less to
be desirable for most people. A BMI between 25 and 30 -- mild or
moderate overweight -- carries a slightly increased risk of
weight-related health problems such as high blood pressure, high
blood cholesterol, heart disease, and Type II (adult-onset)
diabetes. At a BMI of 30 or more -- considered truly overweight
-- the risk of developing those conditions and others rises
sharply.
There is little doubt that people with a *lifelong* BMI of 25 or
less have the lowest risk of disease and premature death (except
for cigarette smoker, who are both lean and suffer high rates of
cancer, chronic lung disease, and cardiovascular disease). But
the benefits of thinness may be greatest for people who have
always been thin. Someone who starts out overweight and then
slims down is still worse off than someone who never was
overweight at all.
The people with the hardest decision to make about their weight
are those who are mildly to moderately overweight, with a BMI
between 25 and 30. If they have diabetes or cardiovascular risk
factors, such as high blood cholesterol or high blood pressure,
they may have a medical reason to try to reduce; if not, they may
be relatively safe.
Age also affects the risk for this middle group. Americans'
median weight rises steadily between the ages of 20 and 55, and a
number of studies indicate that isn't necessarily dangerous. The
overall risk of moderate overweight apparently diminishes, or
even disappears altogether, with advancing age. The reason is not
entirely clear, and the data have been the subject of much
debate. However, most researchers now accept the phenomenon as
fact, as does the U.S. Government. Since 1990, the Government has
published weight guidelines for Americans that give different
ranges for older and younger adults.
One other critical variable has emerged in the last several
years: the waist-to-hip ratio, calculated as the measure of a
person's waist at its smallest point divided by the circumference
of the hips at their widest point. This ratio distinguishes
"apples" -- that is, people who carry excess weight above their
waist -- from "pears," whose extra fat settles around the hips
and buttocks. The higher the waist-to-hip ratio, the more
apple-shaped the figure. Most men are apples, with the classic
beer belly; most women are pears, although there is a significant
minority of female apples.
The correlation between the waist-to-hip ratio and
cardiovascular disease has been investigated in at least a
half-dozen long-term studies, with consistent results: The higher
the ratio, the greater the risk of disease, especially among
people who are at least moderately overweight. Many scientists
even believe that the waist-to-hip ratio predicts cardiovascular
disease better than the degree of overweight. For men, the risk
seems to rise above a waist-to-hip ratio of 0.95; for women, the
cutoff point is 0.80. Paradoxically, surveys show that overweight
men, most of whom are apples, are much less likely to try to lose
weight than women, whose fat distribution is more benign.
Scientists think that abdominal fat does its damage because it is
more metabolically active than below-the-waist fat. It's also
associated with increased insulin resistance (a precursor to
diabetes) and may be a cause of hypertension.
Why diets don't work
Even the most optimistic weight-control professionals admit that
traditional dieting -- cutting calories to lost weight -- rarely
works in the long term. Clinicians have tried everything to make
diets more effective. They've devised ultra-low-calorie regimens
that produce fast, large weight losses. They've brought patients
in for months, even years, of behavior modification to help them
deal with "impulse" eating and distract themselves from hunger
pangs. The results are unvarying: When treatment stops, weight
gain begins.
Scientist can't yet fully explain this nearly inevitable pattern,
but the explanation may lie in our prehistoric roots. According
to one hypothesis, humans evolved under the constant threat of
famine. As a result, the human body is programmed by evolution to
respond to caloric restrictions if starvation were at hand. After
a few weeks on a low-calorie diet, the body goes on a sort of
protective red alert. The basal metabolic rate -- the speed at
which the body burns calories when at rest -- begins to decline.
In addition, the body uses lean muscle mass as fuel in an effort
to preserve fat, which is the major long-term source of energy.
Both changes mean that the body burns fewer calories, making it
more difficult to maintain a weight loss.
Finally, hunger -- true, physiological hunger -- increases. And,
faced with hunger, "people are not able to keep up with the food
restrictions required to maintain a lower weight," says David
Schlundt, a psychologist at Vanderbilt University who specializes
in obesity. Although the folklore of dieting says that hunger can
be overcome by anyone with a decent amount of willpower, this
basic biological drive is exceedingly difficult to ignore.
Most obesity researchers now believe that stringent dieting is
actually a major trigger for binge eating. This connection was
shown vividly in an experiment conducted during World War II by
University of Minnesota physiologist Ancel Keys with a group of
young, healthy men. Keys put the men on a balanced diet that
provided about half their usual caloric intake -- a regimen that
he called "semistarvation" but that was remarkably similar to the
diets prescribed by today's commercial weight-loss programs. When
the men were released from the diet after six months, they went
on massive eating binges, eating up to five meals and 5000
calories a day until they had returned to their normal weight.
The lesson: "Going back to eating after a period of starvation is
as natural as taking a breath," says Susan Wooley, a University
of Cincinnati psychologist who specializes in obesity and eating
disorders.
Is weight loss safe?
In addition to the high physical and emotional cost of dieting,
new epidemiological evidence suggests that the practice may
actually carry a greater health risk than staying overweight for
some people.
For years everyone assumed that if overweight damaged a person's
health, losing weight would improve it. That assumption seemed to
be well-founded: Many studies have shown that as soon as dieters
start to lost weight, their blood cholesterol levels and blood
pressure drop and their insulin resistance declines.
Surprisingly, however, not a single long-term epidemiological
study has ever proven that losing weight extends life. And over
the past year, two important studies have provided evidence to
the contrary.
One, headed by Elsie Pamuk of the Centers for Disease Control and
Prevention, used the results of the First National Health and
Nutrition Examination Survey, a Government survey of the health
status of thousands of Americans. When they entered that study in
the early 1970s, participants were given a complete checkup that,
among other things, recorded what they weighed then and what was
the most they had ever weighed. A decade later, the Government
scientists tracked the participants to see who had died, and of
what causes.
Recently, the CDC team analyzed the records of 5000 men and women
who had been between the ages of 45 and 74 when they entered the
Government study. The goal was to see whether those who had once
been overweight but had lost weight lived longer than peers who
had stayed fat. The team eliminated from the analysis anyone who
had died within five years of starting the study, to make sure a
pre-existing disease had not made them thin. They also adjusted
their data to account for the effects of smoking, age, and
gender.
The analysis did confirm one piece of conventional wisdom:
Maintaining a stable adult weight and avoiding severe overweight
is the best possible course. The data also supported the view
that moderate overweight is not necessarily detrimental in middle
age: Over the period of the study, men and women with a stable
BMI between 25 and 30 had death rates as low as those with a
stable BMI of 25 or less.
But when the CDC analysts looked at the effect of weight loss,
what they found upset all their expectations: Instead of
improving health, losing weight seemed to do the opposite. Women
who lost *any* amount of weight had a higher death rate than
those who didn't; the more weight they lost, the higher their
risk. Among the fattest group of men, who began with a BMI of 30
or above, those who had a moderate weight loss had a slightly
lower than average death rate. But those who lost 15 percent or
more had a higher death rate -- unless, surprisingly, they were
so fat that their weight loss still left them overweight.
The second study was even larger: It included 11,703 middle-aged
and elderly Harvard alumni whose weight was recorded in the early
1960s and again in 1977. Like the CDC study, the Harvard study
controlled for pre-existing disease. The men whose weight changed
least between the 1960s and 1977 had the lowest death rates,
whether the researchers looked at deaths from all causes, deaths
from cancer, or especially, deaths from cardiovascular disease.
Any significant weight change, whether up *or* down, markedly
increased the risk of dying from cardiovascular disease.
Researchers are hard-pressed to explain the findings of the CDC
and Harvard studies. The most likely explanation, however, is
that people whose weight changed the most over time were more
likely to have had cycles of yo-yo dieting in between --
especially if they were overweight. Since our culture stigmatizes
fatness, anyone who has been overweight for more than a few years
has very likely gone through at least one cycle of significant
weight loss and regain. Of the 95,000 respondents to our diet
survey, 40 percent had had two or more weight-loss cycles within
the previous five years; in that survey, overweight people cycled
more often than people of normal weight.
Other studies have suggested that repeatedly losing and gaining
weight is hazardous to health. One recent analysis used data from
the Framingham Heart Study, a long-term study of some 5000
residents of a Boston suburb that began in 1948. compared with
subjects whose weight remained the most stable, those whose
weight fluctuated frequently or by many pounds had a 50 percent
higher risk of heart disease.
Weighing your options
Studies like those will animate seminars at scientific meetings
for years to come. But they're confusing to people who must
decide right now what, if anything, to do about their weight.
For some groups, the decision is relatively clear-cut. People who
are not already overweight should place top priority on avoiding
weight gain through a combination of moderate eating habits and
exercise. Most seriously overweight people -- those with a BMI of
30 or more -- should attempt to lose some weight; for them, the
evidence favoring weight loss is greater than the evidence
against it. Most adult-onset diabetics should also reduce, since
blood-sugar control usually improves with even relatively small
amounts of weight loss. Given the possibility that large losses
and regains may be hazardous, however, the best strategy is to
stay away from quick weight-loss diets and aim instead for slow,
modest, but permanent weight loss using the approaches we'll
describe below.
The choice for nondiabetic, moderately overweight adults is not
so clear. They should do what they can to avoid gaining more
weight. But is is not certain that losing weight in and of itself
will reduce their risk -- especially if they gain it back again.
fortunately, there is an approach to losing weight through diet
and exercise that doesn't involve low-calorie quick-weight-loss
plans. It's safer than conventional dieting; it's more likely to
be effective; and it can lessen the risk of cardiovascular
disease dramatically, even if it doesn't result in a large
weight loss.
The importance of exercise
Apart from the risk of developing shinsplints or being chased by
a dog, there's almost nothing bad to be said about regular,
moderate physical exercise. And a number of studies now show that
exercise can be very effective in weight control.
In one recent study, Stanford University researchers put 71
moderately overweight men and women on a low-fat diet for a year,
and another, matched group of 71 on a diet with the same kinds of
foods -- plus a three-day-a-week program of aerobic exercise.
After a year, the diet-plus-exercise group had lost more weight
overall and more pounds of fat, even though they actually ate
more calories per day than the diet-only group. Other studies
have shown that exercise can help people lose weight even if they
don't change their regular diet at all.
The explanation lies in the nature of human metabolism. More than
half the calories we take in are burned up by what's called basal
metabolism -- the energy expended just to stay alive. In addition
to increasing the number of calories burned in activity, exercise
increases the basal metabolic rate, so the body burns more
calories even at rest. Studies have shown that the basal
metabolic rate is closely linked to the amount of muscle on the
body, which is built up through exercise.
For most people, exercise alone will be enough to prevent future
weight gain; for many, it will enable them to lose weight
effectively and safely. In addition, even if exercise doesn't
help you lose pounds, it may help you become thinner. A pound of
muscle takes up less space than a pound of fat. So as you build
muscle and lose fat, you can lose inches even without actually
losing any weight.
Exercise plays a critical role not only in burning fat, but in
keeping weight off. That was shown dramatically in a study of 184
mildly overweight Massachusetts policemen and civil servants. all
were put on a low-calorie diet, and half were also put through
three 90-minute exercise sessions per week. After eight weeks,
everyone had lost weight. But when the men were re-examined three
years later, those who had never exercised -- or who had stopped
once the study ended -- promptly regained all or most of the
weight they had lost. In contrast, exercisers who kept at it
maintained virtually all their initial weight loss.
The rationale for exercise goes well beyond becoming thinner. "A
lot of the health benefits that people are seeking from weight
loss can be achieved by exercise, even in the absence of any
weight loss," says Steven Blair, director of epidemiology at the
Institute for Aerobics Research in Dallas.
In 1970, scientists at that institute began keeping records on
more than 13,000 then-healthy middle-aged men and women to
determine the effects of physical fitness on cardiovascular risk.
The results are now coming in: Exercise seems to protect against
disease and death even in people whose risk factors would
otherwise put them in danger. Physically fit men in the study who
had high blood pressure, insulin resistance, a high BMI, or an
unfavorable family history were less likely to die than unfit men
with none of those risk factors. Overall, the fittest men in the
study had a death rate less than one-third that of the least fit;
for women, there was a five-fold difference. The rates for
cardiovascular disease were even more dramatically affected by
fitness.
This study has now been followed up by a number of others showing
that, among people with almost any known cardiovascular risk
factor, exercisers do better than nonexercisers. In addition,
exercisers develop adult-onset diabetes about 40 percent less
often than nonexercisers, according to a study of 21,000 male
American doctors.
It may even be that lack of exercise, rather than excess body fat
itself, is the true culprit behind many of the ill effects of
obesity. Since inactivity often leads to weight gain, overweight
may turn out to be more a result of an unhealthful life-style
than a cause of ill health.
Despite the evident benefits of exercise, most people with a
weight problem still choose dieting instead. One reason has been
the exercise community's historic fixation on high-intensity
aerobic exercise, with its intimidating target-heart-rate charts
and elaborate workout schedules. Most people simply won't attempt
such demanding, time-consuming regimens -- especially not the
sedentary, overweight people who have the greatest need to
exercise.
But intense exercise may not be necessary. Blair's study at the
Institute for Aerobics Research suggest that the chief benefits
of exercise come when people go from a sedentary life-style to
moderate activity -- not when they move from moderate exercise to
intense athletics. In that study, men in the moderate-fitness
group had a death rate from all causes nearly 60 percent lower
than that of the sedentary group. In contrast, the very fittest
men had a death rate only 23 percent lower than that of the
moderately fit group. (Moderate exercise was defined as the
equivalent of 30 to 60 minutes a day of brisk walking, either in
small spurts or all at once.)
Influenced by these findings, Blair has become a prominent
advocate of what might be called opportunistic exercise, which is
essentially the art of devising an activity plan that can meet
with any schedule, no matter how frenetic. Blair, like many
fitness experts, recommends looking for exercise everywhere you
can. Park at the far edge of the mall lot instead of next to the
front door; get off a bus one stop early and walk the rest of the
way; pace the floor while you're on the phone; use an
old-fashioned reel-type mower instead of a gasoline-powered one;
take the stairs instead of the elevator. Any kind of exercise,
however mundane, has potential benefits.
Eat less fat, lose fat
In addition to exercise, changing the kinds of foods you eat --
even without changing the caloric content -- can improve both
weight and health. Despite the decades-old wisdom that a calorie
is a calorie is a calorie, some recent studies have suggested
that calories from fat follow a straighter trajectory to the hips
or the belly than calories from other sources. The body can store
fate very efficiently. But the body's ability to store
carbohydrates is limited, so when people eat more than their
bodies can use, the excess is burned.
For that reason, researchers have found than the composition of
the diet may be more important than the number of calories in
determining who gains and who loses weight. The percentage of fat
in the diet was the single strongest predictor of subsequent
weight gain, for example, among 294 adults monitored for three
years by Memphis State University investigators. By contract, the
total calorie consumption they reported had only a weak
relationship to weight gain for women, and none at all for men.
If a high-fat diet can add pounds, a low-fat diet may help take
them off. Researchers at the University of Illinois at Chicago
switched 18 women volunteers from a diet that derived 37 percent
of calories from fat -- roughly the fat content of the average
American's diet -- to a diet that was only 20 percent fat. Over
the 20-week experiment, the women lost four to five pounds, even
though they had increased their caloric intake.
One way to reduce fat intake without feeling chronically hungry
is to fill up on something else, namely fruits, vegetables, and
whole grains. Those foods are all high in carbohydrates, and a
diet rich in fruits and vegetables seems to lower the risk of
cancer and cardiovascular disease.
Some high-fat foods are easier to give up than others, as
scientists at Seattle's Fred Hutchinson Cancer Research Center
found in a study of the relationship between dietary fat and
breast cancer. They taught a large group of women simple ways to
reduce their fat consumption, and tracked down some of the
participants after a year to see if they'd kept up their low-fat
habits. The easiest changes to sustain turned out to be those
that were least noticeable form from a sensory standpoint:
switching to low-fat milk, mayonnaise, margarine, and salad
dressing; trimming fat from meats and skin from chicken; having
occasional vegetarian meals. Hardest to give up were the foods
for which fat was an integral part of the food's appeal: pastries
and ice cream, butter, hamburgers, lunch meats, and cheese.
Fortunately, the fat-reducing strategies that are easiest to
follow can yield a significant decrease in total fat consumption.
A group from Pennsylvania State University calculated the effect
of such changes on an average woman's diet. They determined that
by substituting skim milk for whole, switching to lower-fat meats
and fish (such as skinless chicken and water-packed tuna), and
using low-fat dressings and spreads, a woman could cut the fat in
her diet from 37 percent of calories to 23 percent.
Your natural weight
Exercising and eating less fat are healthful changes that can
benefit anyone, and may lead to weight loss as a bonus. But for
many people, especially those who have been overweight all their
lives, even faithful adherence to healthful habits won't slim the
body to the thin ideal our culture holds dear.
Jane Polivy, an obesity researcher at the University of Toronto,
believes that people should learn to be comfortable with their
"natural weight" -- the body size and shape that results after a
person adopts a healthful diet and gets a reasonable amount of
exercise. Similarly, Kelly Brownell, a Yale University
psychologist who has done extensive research on behavioral
obesity treatments, speaks of a "reasonable weight" as an
attainable goal. "It's the weight that individuals making
reasonable changes in their diet and exercise patterns can seek
and maintain over a period of time," he explains. Brownell
suggests that people who want to lose weight should start by
losing a moderate amount, 10 pounds or so, and should then see
how comfortably they can maintain that lower weight before trying
to lose a bit more, stabilizing again, and so on.
Accepting the goal of a "natural" or "reasonable" weight may
involve giving up long-held fantasies of a slim, youthfully
athletic body, and being content with the realities of a
middle-aged shape instead. It means accepting a slower rate of
weight loss, or none at all. For long-term dieters, many of whom
have spent years monitoring everything they put into their mouths
and suppressing hunger pangs, it also means learning anew how to
eat normally -- eating when hungry and stopping when full.
Nevertheless, we believe this moderate approach to weight control
is the only one worth trying for most people.. It makes sense
whether you are trying to maintain your current weight, reverse
middle-age spread, or deal with a weight problems that's plagued
you all you life. If you change your eating and exercise patterns
gradually, and maintain the changes over time, you will almost
certainly look and feel better, have more energy, and reduce your
risk of cardiovascular disease, whether or not you lose much
weight.
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| RATING THE DIETS
For years, dieters frustrated by cycles of losing and regaining
weight have bounced from one diet fad to the next, from one
commercial program to another, wondering if any of them will
work. Now the Federal Trade Commission is wondering too. In
March,, the FTC announced that it is looking into the advertising
practices of several commercial diet companies, including the
nation's five largest: Diet Center, Jenny Craig Nutri/System,
Physicians Weight Loss Centers, and Weight Watchers. The FTC has
asked for evidence to back up the advertised promises these
companies make that their programs will bring lasting weight
loss.
Diet companies have been notorious for their failure to present
any solid data on their programs' results. Americans now spend
more than $3 billion a year on these programs, but they have had
no solid information on their benefits, if any.
We decided to conduct a survey to help fill the gap by including
a section on weight loss in our 1992 Annual Questionnaire.
Readers who had tried to lose weight at least once during the
previous three years were invited to tell us about their
experience, and 95,000 of them did. Most of them had tried to
lose weight on their own, but almost 19,000 -- one in five -- had
joined professionally managed weight-loss programs. We asked them
to tell us about their weight history -- before using the
program, at the time they finished it, six months later, and at
the time they filled out the questionnaire -- and asked them
several questions about the dieting experience. Using their
responses, we were able to compare the same five diet programs
that are the chief targets of the FTC probe. We also sent
staffers undercover to outlets of those five companies to
experience their sales pitches first-hand.
In addition, our survey gave us information about three other
programs -- Health Management Resources, Medifast, and Optifast
-- which are designed for seriously overweight people. Unlike
regular diet programs, these entail giving up food for a time and
following a very-low-calorie liquid diet under a doctor's
supervision.
We invited each of the eight companies we evaluated to send us
any materials they thought would help us assess their programs.
only Optifast and Jenny Craig provided any information on their
clients' success. The Optifast study was designed well enough for
us to consider it scientifically valid; Jenny Craig's was not.
Ours is the first major scientific survey of the commercial diet
industry. Among our chief findings:
o For most people, commercial weight-loss programs are temporary
palliatives at best. On average, our respondents reported that
they stayed on the programs for about half a year and lost
about 10 to 20 percent of their starting weight. But the
average dieter gained back almost half of that weight just six
months after ending the program, and more than two-thirds of
it after two years (chart of "How Weight Returns Over Time,"
not reproduced here).
o None of the top five diet programs were better than the others
in helping people lose weight during the program or keep it
off six months later. As a group, people on the three
liquid-fast programs did lose weight more rapidly than those
on regular diet programs -- but they gained it back at roughly
the same rate.
o Many people who went on these eight commercial programs had no
clear reason to try to lose weight. More than a quarter of
them did not meet the medical criteria for even moderate
overweight when they started the program. That group of
normal-weight people included a significant fraction of those
who went on liquid-fast programs, which can be especially
hazardous for people who are not obese.
o Overall dissatisfaction with weight-loss programs was higher
than for all other consumer services we have evaluated in
reader surveys over the years. (That dissatisfaction, however,
may partly reflect the fact that diet programs make more
demands on the consumer than most of the other services do.)
Despite all this, a significant minority of our respondents --
about a quarter of them -- did get some apparent benefit from
their weight-loss regimen. Two years after finishing their
program, they had kept off most of the weight they had lost.
That's a better success rate than the often-quoted statistic,
based largely on people in hospital clinics, that 95 percent of
all diets eventually fail. But it's a far more modest success
rate than many dieters are led to expect.
The four major options
Most people who want to lose weight would do well to try the
least costly and difficult strategies first, and consider more
elaborate programs only if those fail. Here are the major
options:
* Self-help
Our survey showed that going it alone was moderately effective
for some people: Those who lost weight on their own shed an
average of 10 pounds.
While the do-it-yourself dieters were somewhat less satisfied
with their initial weight loss than were customers of commercial
diet programs, those who did lose weight were a bit more
satisfied with their ability to keep the weight off. The changes
they made on their own may have been easier to sustain than the
more artificial changes imposed by an outside program.
The strategies used by the do-it-yourself group were, by and
large, simple and sensible. Those people ate less food,
especially fatty foods, snacks, and desserts, and they exercised
more -- all changes, of course, that benefit health even when
they don't produce weight loss.
*Hospital-based programs
Of the respondents who used professionally managed programs to
lose weight, 6 percent chose programs offered by local hospitals.
Hospital-based programs vary enormously in scope and cost, from
free or low-cost nutritional counseling to elaborate,
physician-supervised liquid fasts. Overall, people who enrolled
in hospital programs lost about as much weight, and kept it off
about as well, as people in commercial programs -- and they had
fewer complaints about the hospital based programs.
*Commercial diet programs
More than 80 percent of the readers who sought help in losing
weight chose one of the five largest commercial diet programs..
These programs generally attract women who have a moderate weight
problem and men who are moderately to seriously overweight. The
women in these programs averaged 167 pounds when they started and
a body mass index, or BMI, of 28; the men, 217 pounds and a BMI
of 31. (A BMI of 25 or less is considered desirable, while most
people with a BMI of 30 or more are seriously overweight; for
more on the body mass index, see [later reply]).
But diet programs also attracted a significant number of people
-- about 30 percent of the readers who used them in our survey --
who had a BMI of 25 or less. Such people have no clear medical
reason to try to lose weight.
These programs all include a low-calorie diet of about 1000 to
1500 calories a day and some kind of counseling to help dieters
deal with the temptations presented by eating out or social
occasions. All claim to stress exercise as much as diet. But we
found that most of them, in practice, give exercise second
billing at best.
*Liquid fasts
These are the most drastic weight-loss programs, designed for
people with a serious weight problem. Only about 6 percent of the
respondents who lost weight with professional help had used
liquid fasts. These fasting programs require people to give up
solid foods altogether for a time and subsist on flavored liquid
formulas that supply between 450 and 800 calories a day. Dieters
typically fast for three months, during which time they should
receive counseling on how to improve their eating habits. Then
they are gradually weaned off the formula and put back on solid
foods.
These near-starvation rations produce very fast weight loss but
often cause medical complications. The informed-consent form for
Optifast clients warns that they may experience such
"adjustments" as dizziness, sensitivity to cold, slower heart
rate, brittle nails, rashes, fatigue, diarrhea or constipation,
muscle cramps, and bad breath. Weight loss from very-low-calorie
diets is known to cause gallstones, and has been linked to
potentially fatal heart-rhythm disturbances -- particularly in
relatively thin people who try the programs.
Liquid-fast programs are available only through hospitals or
doctors' offices and require regular physical checkups and blood
tests. They generally cost between $2000 and $3000.
--------------------
The eight programs we evaluated are essentially based on a single
principle: cutting calories. But we found significant differences
in their approaches and in our readers' satisfaction with them.
here are the pros and cons of each.
Weight Watchers
Weight Watchers, founded by a self-described Brooklyn housewife
in 1963, is the oldest of the weight-loss programs we evaluated.
It holds an overwhelming market share. In our survey, it was
chosen by 43 percent of those who used professional help to lose
weight, far more than the number using any other program. Readers
who chose Weight Watchers were also significantly more satisfied
than those who went to any of its competitors.
"Weight Watchers is the only place I ever send anyone," says
Janet Polivy, a University of Toronto psychoogist who treats
people with eating disorders and generally warns clients away
from the very idea of dieting. "Weight Watchers is the most
sensible," she says.
Of all the programs we evaluated, Weight Watchers is the only one
that relies exclusively on group counseling. Each counselor
employed by Weight Watchers is a former client who has achieved
and maintained his or her "goal weight" on the program. Gaining
it back is grounds for dismissal.
Dieters pay an enrollment fee -- a CU staffer paid $15 at a local
outlet -- and are given a diary to record their goal weight and
the results of a weekly weigh-in. They are then entitled to
attend any weekly Weight Watchers session anywhere as long as
they pay the weekly meeting fee ($12 at the center we visited,
but it varies from place to place). Some groups are held in
Weight Watchers retail outlets, while others meet in community
centers or churches, or at work. The program costs significantly
less than the others we rated: Questionnaire respondents spent an
average of $110 for several months' worth of counseling. Weight
Watchers is also the only diet program that doesn't require
customers to buy any company-brand foods or nutritional
supplements. (It does, however, shower participants with
cents-off coupons for the many types of Weight Watchers-brand
foods sold in supermarkets.)
The Weight Watchers diet is a standard low-calorie regimen, high
in carbohydrates and low in fat. According to Weight Watchers
material, if a dieter is losing more than 1 percent of body
weight per week -- that usually translates into 1-1/2 to 2 pounds
-- then he or she will be instructed to eat more to slow down the
rate of loss. This practice, unique among the programs we
studied, fits with current medical thinking about the hazards of
too-rapid weight loss.
Weight Watchers clients in our survey did no better at losing
weight than people on other commercial diets. Nevertheless, our
Weight Watchers respondents said they were more satisfied with
their weight loss and with their overall experience than were
people who went to any other diet chain. Compared with customers
of the typical diet program, Weight Watchers customers
experienced less sales pressure, had fewer problems with the
diet, felt less hungry, and were less often surprised by
unexpectedly high costs.
Company-food programs
Nutri/System, chosen by 18 percent of our respondents, and Jenny
Craig, chosen by 11 percent, each require that dieters buy and
consume only company-brand foods (except for a few items such as
fresh dairy products and produce). Jenny Craig sells both frozen
and shelf-stable foods, while Nutri/System has shelf-stable
selections only. The foods cost about $60 to $70 every week for
most participants; the cost drops slightly as you approach your
goal weight and start eating some regular food. In addition,
readers who used these programs paid higher fees than those who
chose Weight Watchers -- an average of $189 for our Jenny Craig
respondents and $292 for Nutri/System.
The companies assert that their prepackaged meals help dieters
learn "portion control" by giving them a sense of how much food
they can eat to maintain a given calorie level, and also free
them from the need to weigh or measure every morsel they ingest.
That rationale aside, the prepackaged foods have a clear benefit
for the companies: the annual report for Jenny Craig Inc. notes
that, in 1992, food sales account for 90 percent of revenues from
the company's centers.
The mandatory food purchases irritated our readers. More than
half complained that the two companies applied "strong pressure
to buy their products" -- by far the highest response on this
problem area. Yet when one of our staffers asked to buy sample
foods before signing up for the full program, to make sure she
liked them well enough to face the prospect of eating them for
several months straight, her request was politely but firmly
turned down at both programs.
Both Nutri/System and Jenny Craig use one-on-one counseling for
clients, augmented by group classes in behavior modification.
Business is generally conducted in a storefront facility, which
also serves as a pickup point for the week's supply of food.
In their literature, both these programs make reference to
exercise. But at one Jenny Craig outlet, a CU staffer was told
that if she wanted the set of walking-program audiotapes, she
would have to purchase a special $94 "Lifestyle Counseling
Package."
The two programs' literature seems designed to inspire rather
than inform. Jenny Craig gives prospective customers a slick
brochure that focuses more on the company's new rebate offers
than on specifics of the weight-loss program itself. The brochure
is illustrated with a number of full-color, full-length
photographs of a young woman said to have lost 62 pounds on the
program and to have gone from a size 16 to a size 6. The same
preoccupation with clothing dominates the Nutri/System
promotional materials. The company's "Nutri/Size Your Body"
advertising campaign has featured slimmed-down, satisfied
customers holding up billowing clothing from their fatter days.
Such ads have drawn criticism from many clinicians specializing
in weight loss. "Those commercials make me go absolutely
ballistic," exclaims David Schlundt, a Vanderbilt University
psychologist who treats people with eating disorders. "The
majority of people who need to lose weight would be much better
off if they dropped to a size 12; their chances of dropping to a
size 6 are almost zero. These ads are not selling health
benefits, they're playing on a tremendously emotional issue in
people's lives."
Certainly, most Nutri/System customers who responded to our
questionnaire won't be in a size 6 anytime soon. Our average
woman who used Nutri/System started at 167 pounds and ended up,
six months after completing the program, with a net loss of just
over 11 pounds.
Other diet plans
The remaining two diet chains of the five in our survey, Diet
Center and Physicians Weight Loss Center (PWL), were chosen by
the smallest number of readers. They provide a mix of elements
found in other programs: They focus on diet plans using ordinary
foods, as Weight Watchers does, but use individual counselors as
Jenny Craig and Nutri/System do. PWL also requires dieters to
spend about $20 a week for a daily nutritional supplement, while
Diet Center's plan includes a daily vitamin pill as part of the
fee for the program.
Until the late 1980s, PWL had by far the lowest-calorie plan of
any of the commercial companies, offering a mere 700 calories a
day. In 1990, the company increased its daily calorie count to
between 900 and 1000 -- still on the low side, but within the
range for regular diet programs. Nevertheless, our survey showed
the PWL did not produce significantly better weight loss or
weight maintenance than other programs that allow their clients
more food.
Liquid fasts: A last resort
In our survey, people on these programs lost a great deal more
weight than customers of regular diet programs - an average of 15
to 20 percent of their starting weight, versus 8 to 12 percent
for the diet programs -- in about the same amount of time.
However, they also regained the weight quickly.
Liquid fasts are generally appropriate only for people with a BMI
in the 30s, or people with BMIs in the high 20s who have a
serious weight-related risk factor, such as severe high blood
pressure or diabetes. Most readers who used liquid fasts fit
those criteria: The men weighed on average 250 pounds to start,
and the women 203 pounds, with BMIs of 35 and 34 respectively.
But we also found than one-sixth of our respondents who tried
liquid fasts said they had a BMI of 25 or less when they started
the program: They were not actually overweight at all. For such
people, going on a liquid fast could pose a serious risk to
health.
Although they produced roughly comparable weight-loss results,
the three liquid-fast programs we evaluated -- Health Management
Resources (HMR), Medifast, and Optifast -- got different marks
from our respondents. Clients of HMR were the most satisfied with
the program overall, and complained less frequently than Optifast
or Medifast clients about unhelpful weight-loss counselors and
unexpectedly high costs. HMR has now become the market leader
among liquid fasts, surpassing Optifast in sales. Readers who
went to either HMR or Optifast maintained their weight
significantly better than Medifast customers after six months.
People who tried Optifast, the oldest of the liquid-fast
programs, lost 45 pounds on average and had gained back 15 pounds
six months later. That relapse rate is similar to the study of
customers that we were sent by Optifast, the only weight-loss
company we contacted that had done a careful scientific study of
its success rate. (Optifast was also the program Oprah Winfrey
used when she lost 67 pounds in a highly publicized effort a few
years ago -- and then, just as publicly, gained it all back.)
Recommendations
Despite their sales pitches, there is no evidence that commercial
weight-loss programs help most people achieve significant,
permanent weight loss. If you want or need to lose weight, you
would probably do well to try to reduce on your own, or through a
free hospital-based program, before spending money on a
commercial weight-loss center.
Some people may find they can control their weight better if they
have outside support, which is essentially what the commercial
programs supply. Any program can produce significant weight loss
fairly rapidly. The trick is in keeping it off -- and the great
majority of dieters don't.
We did find that about one-fourth of our readers who used
commercial diet programs were able to keep off most of the weight
they'd lost for two years. But we found nothing that gave us a
clue to their success; successful maintainers were not
significantly different from ordinary dieters in terms of the
time they had spent in the weight-loss program, their starting
weights, or their sex.
Since no diet program was especially effective, anyone who wants
to play the commercial-diet game should choose a program on the
basis of cost, comfort, and common sense. By those criteria,
Weight Watchers was our readers' clear favorite. it costs less
than the others, emphasizes healthful dietary habits, encourages
relatively slow weight loss, and generally appears to provide the
most satisfying, supportive experience. In contrast, Nutri/System
and Jenny Craig cost more, are more likely to use high-pressure
sales tactics, and were not as satisfying to clients overall.
No one should go on a liquid-fast program without a compelling
medical reason to do so. Among the liquid-fast programs, Health
Management Resources seems the best, in terms of our readers'
satisfaction.
None of the diet programs we investigated give top priority to
increasing physical activity, a change that researchers now
unanimously agree is critical to lasting weight loss. If you use
one of these programs, you should be prepared to find a way to
exercise on your own.
Most important, given the strong likelihood that any weight lost
on a reducing diet will be gained back promptly,l we recommend
that anyone contemplating a diet think seriously about whether
losing weight is necessary or desirable in the first place. As
our survey and others have shown, many people diet even though
they are not overweight. For reasons the previous report makes
clear, the majority of dieters would probably do better to forget
about cutting calories, focus on exercising and eating a
healthful diet, and let the pounds fall where they may.
-----------------------------------------
Narrative from chart:
HOW LOST WEIGHT RETURNS OVER TIME
Winners and loser at weight loss. Readers who went through a
commercial diet program typically regained half their lost weight
in a year and much of the rest in another year (a pattern shown
here as the "median" line). But experience varies. When we looked
at the one-quarter of our sample who regained the most weight, we
found these "worst maintainers" typically regained all their
weight, or more, within nine months. In contrast, the quarter of
our sample who were the "best maintainers" had kept off more than
two-thirds of their weight, on average, after two years. These
figures are for people on the five commercial diet programs; the
pattern for liquid-fast programs was similar.
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