The Atkins Diet - Big Fat Lies, Ebooks
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NOVEMBER 2002 VOLUME 29 / NUMBER 9
CENTER FOR SCIENCE IN THE PUBLIC INTEREST
$2.50
HEALTH LETTER
TM
The Truth
About the
Atkins Diet
By Bonnie Liebman
“What If It’s All Been a Big Fat Lie?”
asked the cover story of the July 7th
New York Times Magazine
. The arti-
cle, by freelance writer Gary Taubes,
argues that loading our plates with
fatty meats, cheeses, cream, and but-
ter is the key not just to weight loss,
but to a long, healthy life.
“Influential researchers are begin-
ning to embrace the medical heresy
that maybe Dr. Atkins was right,”
writes Taubes.
Taubes claims that it’s not fatty
foods that make us fat and raise our
risk of disease. It’s carbohydrates.
And to most readers his arguments
sound perfectly plausible.
Here are the facts—and the fic-
tions—in Taubes’s article, which
has led to a book contract with a
reported $700,000 advance. And
here’s what the scientists he quoted
—or neglected to quote—have to
say about his reporting.
(Continued on page 3)
COVER ST
erhaps the most telling state-
ment in Gary Taubes’s
New
York Times Magazine
article
comes as he explains how diffi-
cult it is to study diet and
health. “This then leads to a research lit-
erature so vast that it’s possible to find at
least some published research to support
virtually any theory.”
He got
that
right. It helps explain why
Taubes’s article sounds so credible.
“He knows how to spin a yarn,” says
Barbara Rolls, an obesity expert at
Pennsylvania State University. “What
frightens me is that he picks and chooses
his facts.”
She ought to know. Taubes inter-
viewed her for some six hours, and she
sent him “a huge bundle of papers,” but
he didn’t quote a word of it. “If the facts
don’t fit in with his yarn, he ignores
them,” she says.
Instead, Taubes put together what
sounds like convincing evidence that
carbohydrates cause obesity.
“He took this weird little idea and blew
it up, and people believed him,” says John
Farquhar, a professor emeritus of
medicine at Stanford University’s Center
for Research in Disease Prevention.
Taubes quoted Farquhar, but misrepre-
sented his views. “What a disaster,” says
Farquhar.
Others agree. “It’s silly to say that car-
bohydrates cause obesity,” says George
Blackburn of Harvard Medical School and
the Beth Israel Deaconess Medical Center
in Boston. “We’re overweight because
we overeat calories.”
It’s not clear how Taubes thought he
could ignore—or distort—what
researchers told him. “The article was
written in bad faith,” says F. Xavier Pi-
Sunyer, director of the Obesity Research
Center at St. Luke’s-Roosevelt Hospital
Center in New York. “It was irresponsi-
ble.”
Here’s a point-by-point response to
Taubes’s major claims.
The
Truth
About
the
Atkins
Diet
CLAIM
#
1
:
The experts recom-
mend an Atkins diet.
TRUTH
:
They don’t.
An Atkins diet is loaded with meat,
butter, and other foods high in satu-
rated fat. Taubes implies that many of
the experts he quotes recommend it.
Here’s what they say:
n
According to Taubes, Harvard
University’s Walter Willett is one of the
“small but growing minority of estab-
lishment researchers [who] have come
to take seriously what the low-carb-diet
doctors have been saying all along.”
True, Willett is concerned about the
harm that may be caused by high-
carbohydrate diets (see “What to Eat,”
page 7). But the Atkins diet? “I cer-
tainly don’t recommend it,” he says.
His reasons: heart disease and cancer.
“There’s a clear benefit for reducing
cardiovascular risk from replacing
unhealthy fats—saturated and trans—
with healthy fats,” explains Willett,
who chairs Harvard’s nutrition depart-
ment. “And I told Taubes several times
that red meat is associated with a higher
risk of colon and possibly prostate can-
cer, but he left that out.”
n
“The article was incredibly mislead-
ing,” says Gerald Reaven, the pioneer-
ing Stanford University researcher,
now emeritus, who coined the term
“Syndrome X.” “My quote was cor-
rect, but the context suggested that I
support eating saturated fat. I was
horrified.”
Gary Taubes
tricked us all
into coming
across as
supporters
of the
Atkins diet.
“I was greatly offended at how Gary
Taubes tricked us all into coming across
as supporters of the Atkins diet,” says
Stanford’s John Farquhar.
Taubes’s article ends with a quote
from Farquhar, asking: “Can we get the
low-fat proponents to apologize?” But
that quote was taken out of context.
“What I was referring to wasn’t that
low-fat diets would make a person gain
”
— John Farquhar
Stanford University
››››
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COVER STORY
weight and become obese,” explains
Farquhar. Like Willett and Reaven, he’s
worried that too much carbohydrate
can raise the risk of heart disease.
“I meant that in susceptible individu-
als, a
very
-low-fat [high-carb] diet can
raise triglycerides, lower HDL [‘good’]
cholesterol, and make harmful, small,
dense LDL,” says Farquhar.
Carbohydrates are not what has
made us a nation of butterballs, how-
ever. “We’re overfed, over-advertised,
and under-exercised,” he says. “It’s the
enormous portion sizes and sitting in
front of the TV and computer all day”
that are to blame. “It’s so gol’darn
obvious—how can anyone ignore it?”
“The
Times
editor called and tried to
get me to say that low-fat diets were
the cause of obesity, but I wouldn’t,”
adds Farquhar.
My quote was
correct, but
the context
suggested
that I support
eating satu-
rated fat. I was
horrified.
CLAIM
#
4
:
We’re fat because we
ate a low-fat diet.
TRUTH
:
We never ate a low-fat
diet.
“At the very moment that the govern-
ment started telling Americans to eat
less fat, we got fatter,” says Taubes.
“We ate more fat-free carbohydrates,
which, in turn, made us hungrier and
then heavier.”
It’s hard to believe this claim passed
the laugh test at
The Times.
If you
believe Taubes, it’s not the 670-calorie
Cinnabons, the 900-calorie slices of
Sbarro’s sausage-and-pepperoni-stuffed
pizza, the 1,000-calorie shakes or
Double Whoppers with Cheese, the
1,600-calorie buckets of movie theater
popcorn, or the 3,000-calorie orders of
cheese fries that have padded our back-
sides. It’s only the low-fat Snackwells,
pasta (with fat-free sauce), and bagels
(with no cream cheese).
“It’s preposterous,” says Samuel
Klein, director of the Center for Human
Nutrition at the Washington University
School of Medicine in St. Louis.
“There’s no real evidence that low-fat
diets have caused the obesity epi-
demic.”
Taubes argues that in the late 1970s,
health authorities started telling
Americans to cut back on fat, and that
we did. Wrong.
According to the U.S. Department of
Agriculture,
added
fats (oils, shortening,
lard, and beef tallow) have gone up
steadily since the late 1970s (see
“Hardly a Low-Fat Diet”).
Total
fats
(which include the fat in meats, cheese,
and other foods) have also gone up,
though not as steadily.
So how can Taubes write that “the
major trends in American diets, accord-
ing to USDA agricultural economist
Judith Putnam, have been a decrease in
the percentage of fat calories and a
‘greatly increased consumption of car-
bohydrates’”?
The key is the word “percentage.”
The percentage of fat calories in our
diets declined because, while we ate
more fat calories, we ate even more
carbohydrate calories.
“We’re eating roughly 500 calories
a day more than we did in 1980,”
Putnam told us. “More than a third of
the increase comes from refined grains,
a fifth comes from added sugars, and a
third comes from added fats.”
”
— Gerald Reaven
Stanford University
CLAIM
#
3
:
Health authorities
recommended a low-fat diet as
the key to weight loss.
TRUTH
:
They didn’t.
“We’ve been told with almost religious
certainty by everyone from the Surgeon
General on down, and we have come
to believe with almost religious cer-
tainty, that obesity is caused by the
excessive consumption of fat, and that
if we eat less fat we will lose weight and
live longer,” writes Taubes.
It’s true that some diet books, notably
Dean Ornish’s
Eat More, Weigh Less
,
have encouraged people to eat as much
fat-free food as they want. (Of course,
Ornish is talking about fruits, vegeta-
bles, and whole grains, not fat-free
cakes, cookies, and ice cream.) But
“everyone from the Surgeon General
on down” is baloney.
“The Surgeon General’s report doesn’t
say that fat causes obesity,” says
Marion Nestle, who was managing edi-
tor of the report and is now chair of the
nutrition and food studies depart-ment
at New York University. “Fat has twice
the calories of either protein or carbo-
hydrate. That’s why fat is fattening
unless people limit calories from every-
thing else.”
And health authorities like the
American Heart Association; National
Heart, Lung, and Blood Institute; and
U.S. Department of Agriculture never
urged people to cut way back on fat.
Their advice: “Get no more than 30
percent of calories from fat.” At the
time that advice was issued, the average
person was eating 35 percent fat.
CLAIM
#
2
:
Saturated fat
doesn’t promote heart disease.
TRUTH
:
It does.
If there’s any advice that experts agree
on, it’s that people should cut back on
saturated fat. They’ve looked not just
at its effect on cholesterol levels, but on
its tendency to promote blood clots, raise
insulin levels, and damage blood vessels.
They’ve issued that advice after exam-
ining animal studies, population stud-
ies, and clinical studies.
1-3
Taubes dis-
misses them with one narrow argument.
Saturated fats, he writes, “will elevate
your bad cholesterol, but they will also
elevate your good cholesterol. In other
words, it’s a virtual wash.”
Experts disagree. “Fifty years of
research shows that saturated fat and
cholesterol raise LDL [‘bad’] choles-
terol, and the higher your LDL, the
higher your risk of coronary heart dis-
ease,” says Farquhar. Yet Taubes has no
qualms about encouraging people to
eat foods that raise their LDL.
He’s willing to bet that higher HDL
(“good”) cholesterol will protect them.
No experts—at the American Heart
Association; National Heart, Lung, and
Blood Institute; or elsewhere—would
take that risk.
“The evidence that raising HDL is
protective is less solid than the evi-
dence that raising LDL is bad,” says
David Gordon, a researcher at the
National Heart, Lung, and Blood
Institute.
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COVER STORY
Government surveys show no
change—or a slight decrease—in fat
consumption since the late 1970s. But
they don’t look at how much fat is pro-
duced, how much is sold, and how
much is wasted. The surveys simply
ask consumers what they eat. And it’s
possible that once people were told to
eat less fat, they (consciously or uncon-
sciously) started under-reporting how
much they ate.
Says Putnam: “People don’t ade-
quately report added fats, added sugars,
and refined grains.”
The bottom line: Taubes blames the
obesity epidemic on a low-fat diet that
the nation never ate.
The result is
hunger and a
craving for more
carbohydrates.”
It sounds con-
vincing, but
there’s a problem:
“It’s not proven
at all,” says Penn
State’s Barbara
Rolls. “We have
no firm data that
glycemic index
affects body
weight or how
full people feel
after eating.”
Harvard’s
David Ludwig has
done a few stud-
ies on glycemic
index and weight.
In the largest, he
found that 64
overweight ado-
lescents who were
told to eat lower-
glycemic-index
foods lost an
average of four
pounds, while 43
overweight adolescents who were told
to make modest cuts in calories and fat
gained three pounds.
4
“It’s hard to tease apart what led to
the weight loss in that study,” explains
Rolls, “because calorie density, fiber,
and glycemic index all go hand in
hand.”
In other words, foods with a low
glycemic index—most vegetables,
fruits, and whole grains—are also high
in fiber and low in calorie density.
What’s more, Ludwig’s study didn’t
randomly assign children to one diet or
another, so the two groups weren’t
comparable. “The low-glycemic-index
group had fewer minorities,” says
Columbia’s Pi-Sunyer. Whites in both
groups were more likely to lose weight.
And he and others question the
whole glycemic index theory.
5
Among
his criticisms: “People eat meals, where
low-glycemic foods balance out high-
glycemic foods.”
For example, “people don’t eat pasta
alone,” he explains. “They eat it with
olive oil, clams, tomatoes, or other
foods, and that dampens the differ-
ences in their effects on insulin.”
And, contrary to Taubes’s claims,
Hardly a Low-Fat Diet
Added Fats & Oils in the Food Supply
CLAIM
#
5
:
Carbs, not fats, cause
obesity.
TRUTH
:
The evidence blaming
obesity on carbs is flimsy.
The evidence that carbohydrates make
you fat can be called “Endocrinology
101,” says Taubes, implying that it’s
well-established fact. In a nutshell,
Endocrinology 101 says that “we’re hun-
grier than we were in the ‘70s” because
we’re eating more carbohydrates.
“Sugar and starches like potatoes and
rice, or anything made from flour, like
a slice of white bread,” are “known in
the jargon as high-glycemic-index car-
bohydrates, which means they are
absorbed quickly into the blood,”
explains Taubes.
“As a result they cause a spike of
blood sugar and a surge of insulin
within minutes. The resulting rush of
insulin stores the blood sugar away
and a few hours later, your blood sugar
is lower than it was before you ate....
According to Taubes, a low-fat diet has made us fat. Yet our con-
sumption of all added fats combined (red line) is higher than ever
before. Estimates of
total
fat (not shown), which includes the fats
in meats, dairy, etc., also show a rise since the late 1970s. The bot-
tom line: Americans never went on a low-fat diet.
Source: USDA/Economic Research Service.
there is no good evidence that insulin
triggers weight gain. “Insulin crosses the
blood-brain barrier and turns off food
intake,” says Pi-Sunyer. “That makes
sense. You’ve just eaten, so you don’t
need to eat for a while. If anything,
insulin should lower food intake.”
CLAIM
#
6
:
The Atkins diet is
the best way to lose weight.
TRUTH
:
We don’t know the best
way to lose weight.
“Until we have more research, no one
has the solution to the safest and most
effective weight loss,” says Washington
University’s Samuel Klein.
“Preliminary data from several stud-
ies suggest that, at least over the short-
term, the Atkins diet is superior to a
low-fat diet in a free-living environ-
ment,” he says. “But it’s too early to
say that the Atkins diet is better.”
Even if ongoing studies show that
the Atkins diet promotes weight loss,
we won’t know if other diets—ones
high in unsaturated fat or protein or
vegetables and whole grains, for exam-
ple—would work as well or better.
››››
There’s no real
evidence that
low-fat diets
have caused
the obesity
epidemic.
”
—Samuel Klein
Washington University
School of Medicine
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It’s preposterous.
COVER STORY
“We need lots more randomized
controlled trials to evaluate the differ-
ent permutations,” says Walter Willett.
(He and Blackburn are embarking on a
study testing a high-
unsaturated
-fat
Mediterranean diet, not the high-
saturated
-fat Atkins diet, as Taubes
implies.)
“What’s important is not theories,
but evidence.”
the other if it can hurt your bones?”
The problem: All the protein that
Atkins recommends leads to acidic
urine.
6
“And there’s no dispute that an
acid urine leaches calcium out of
bones,” says Blackburn.
“You can buffer the diet by taking a
couple of Tums a day, but now we’re
into medical supervision of people on
the diet,” he adds.
Blackburn and others also want to
know whether an Atkins diet makes the
blood vessels less elastic. “Studies sug-
gest that a diet high in animal fats may
cause blood vessels to constrict,” he
says. “That’s a root cause of atheroscle-
rosis.”
In preliminary studies, the LDL
(“bad”) cholesterol of people on the
Atkins diet didn’t go up. That’s com-
forting. (Of course, LDL didn’t go
down
either, as it usually does with weight
loss.)
“The harm caused by saturated fat
could be overcome by weight loss,”
Klein explains. But what happens once
people stop losing weight and start try-
ing to maintain the loss? Will their
LDL climb? “We don’t know.”
referring to. In 1998, the National
Heart, Lung, and Blood Institute issued
guidelines to help doctors treat obesity.
7
Its conclusion: People who are told
to cut fat (but not calories) lose some
weight because they inadvertently eat
fewer calories. But people who cut fat
and
watch calories lose more.
“A low-fat diet helps people eat fewer
calories,” says Rena Wing, a professor
of psychiatry and human behavior at
the Brown University Medical School
in Providence, Rhode Island. “Maybe
people
want
to hear that if they eat a
lower-fat diet they don’t have to eat
fewer calories, but that’s not true.”
What about Taubes’s claim that low-
fat diets are a failure “in real life”?
Wing’s National Weight Loss
Registry keeps track of people—so far,
about 3,000—who report having lost at
least 30 pounds and having kept the
weight off for at least six years.
8
The
registry can’t “prove”
which
diet is best
because it’s not a controlled experi-
ment. But it does offer evidence of
what works in the long run.
“People on low-carbohydrate diets
like Atkins’s are very rare in the reg-
istry,” says Wing.
“The people in our registry consis-
tently report eating around 24 percent
of calories from fat,” she adds. They also
expend roughly 2,800 calories a week—
that’s like walking four miles a day.
Furthermore, a low-fat diet aided
weight loss in a six-year study of 3,200
people called the Diabetes Prevention
Program.
9
“Patients were put on a low-fat diet
with about 25 percent of calories from
fat and they participated in 150 minutes
of physical activity a week,” says Wing.
“They lost about seven percent of
their body weight and kept most of it off
for four years. And they reduced their
risk of diabetes by 58 percent.”
Of course, it was both diet
and
exer-
cise that led to their success. But if a
low-fat diet
promotes
weight gain, as
Taubes argues, the exercise—only
about 20 minutes a day—would have
had to not only counter the fattening
effects of the low-fat diet, but actually
lead to weight loss. Unlikely.
CLAIM
#
7
:
The Atkins diet
works because it cuts carbohy-
drates.
TRUTH
:
If the Atkins diet
works, it’s not clear why.
If the Atkins diet
does
work, it may
have nothing to do with the glycemic
index or Atkins’s promises. “It’s
unlikely to be related to the explana-
tion in Atkins’s book,” says Klein,
“because that doesn’t make physio-
logical sense.”
Other possibilities: In one study, the
people on a low-carb diet were told to
follow
Dr. Atkins’ New Diet Revolution
,
which could have been more persua-
sive than what the people on a lower-
fat diet got—a manual designed by
academics.
Or, says Klein, “it may simply be eas-
ier to cut carbs.” Everyone knows what
they are: bread, pasta, rice, potatoes,
sweets, etc.
Or, the monotony of a low-carb diet
could have curbed the dieters’ appetites.
“You lose a lot of foods when you cut
out carbs,” says Klein. And with less
variety, says Blackburn, “people eat
less, so they lose more weight.”
“It’s also possible that a chemical is
released by a high-fat diet that sup-
presses the appetite,” adds Klein. “We
just don’t know.”
It’s silly to say
that carbohy-
drates cause
obesity. We’re
overweight
because we
overeat calories.
”
—George Blackburn
Harvard University
CLAIM
#
8
:
The Atkins diet is safe.
TRUTH
:
It isn’t.
Taubes not only neglects to mention
that the meat in an Atkins diet may
promote cancer. He ignores some
researchers’ concerns about other
adverse effects.
“The Atkins diet may produce more
weight loss in the first three weeks, but
it’s not spectacular,” says Harvard’s
George Blackburn. “Who cares if one
group loses a few more pounds than
CLAIM
#
9
:
Low-fat diets don’t
help people lose weight.
TRUTH
:
Low-fat diets work if
dieters cut calories.
“Low-fat weight-loss diets have proved
in clinical trials and real life to be dis-
mal failures,” writes Taubes.
It’s not clear which clinical trials he’s
6
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