| |
WHAT IF ITS ALL BEEN A BIG
FAT LIE?
WEIGHT LOSS WITH A LOW-CARBOHYDRATE,
MEDITERRANEAN, OR LOW-FAT DIET
STUDY SURPRISE: LOW CARB DIETERS EAT
MORE, LOSE WEIGHT
LOW CARB DIETS COMBAT METABOLIC SYNDROME
LOW CARB DIETS IMPROVE CHOLESTEROL EVEN WITHOUT
WEIGHT LOSS
What if its all been a big fat lie?
By Gary Taubes
This is the article that finally convinced me that low carb is
the best way to diet. It is something that everybody who wants
to go on a diet whether it is low fat or low carb should read.
This is a long article, and I'm going to comment on parts of it,
but most of it makes a lot of sense to me.
If the members of the American medical establishment were to
have a collective
find-yourself-standing-naked-in-Times-Square-type nightmare,
this might be it.
They spend 30 years ridiculing Robert Atkins, author of the
phenomenally-best-selling ''Dr. Atkins' Diet Revolution'' and
''Dr. Atkins' New Diet Revolution,'' accusing the Manhattan
doctor of quackery and fraud, only to discover that the
unrepentant Atkins was right all along. Or maybe it's this: they
find that their very own dietary recommendations -- eat less fat
and more carbohydrates -- are the cause of the rampaging
epidemic of obesity in America. Or, just possibly this: they
find out both of the above are true.
The perversity of this alternative hypothesis is that it
identifies the cause of obesity as precisely those refined
carbohydrates at the base of the famous Food Guide Pyramid --
the pasta, rice and bread -- that we are told should be the
staple of our healthy low-fat diet, and then on the sugar or
corn syrup in the soft drinks, fruit juices and sports drinks
that we have taken to consuming in quantity if for no other
reason than that they are fat free and so appear intrinsically
healthy. While the low-fat-is-good-health dogma represents
reality as we have come to know it, and the government has spent
hundreds of millions of dollars in research trying to prove its
worth, the low-carbohydrate message has been relegated to the
realm of unscientific fantasy.
And who is behind the food guide pyramid? Who pays for the
research on that pyramid? What foods are cheaper to manufacture
and store? What foods make more money for businesses? And who
profits from that and the obesity epidemic they have created?
Now, there is a certain junk food company who is touting their
junk food as being healthier than other junk food. It's made
with whole grain, it's made using less/no trans fat, it has less
salt/sugar, it's baked not fried, blah blah blah. Everyone is
jumping on the obesity epidemic needs to be stopped bandwagon
and they are ignoring the research that tells them they created
it and continue to fuel it with their emphasis on whole grains
and low-fat this, that, and the other. I'm not saying whole
grains are bad for you, they're not. But I am asking "Do we
really need to eat five or more servings a day?"
The alternative hypothesis also comes with an implication that
is worth considering for a moment, because it's a whopper, and
it may indeed be an obstacle to its acceptance. If the
alternative hypothesis is right then it strongly suggests that
the ongoing epidemic of obesity in America and elsewhere is not,
as we are constantly told, due simply to a collective lack of
will power and a failure to exercise. Rather it occurred, as
Atkins has been saying (along with Barry Sears, author of ''The
Zone''), because the public health authorities told us
unwittingly, but with the best of intentions, to eat precisely
those foods that would make us fat, and we did. We ate more
fat-free carbohydrates, which, in turn, made us hungrier and
then heavier. Put simply, if the alternative hypothesis is
right, then a low-fat diet is not by definition a healthy diet.
In practice, such a diet cannot help being high in
carbohydrates, and that can lead to obesity, and perhaps even
heart disease. ''For a large percentage of the population,
perhaps 30 to 40 percent, low-fat diets are counterproductive,''
says Eleftheria Maratos-Flier, director of obesity research at
Harvard's prestigious Joslin Diabetes Center. ''They have the
paradoxical effect of making people gain weight.''
What's more, the number of misconceptions propagated about the
most basic research can be staggering. Researchers will be
suitably scientific describing the limitations of their own
experiments, and then will cite something as gospel truth
because they read it in a magazine. The classic example is the
statement heard repeatedly that 95 percent of all dieters never
lose weight, and 95 percent of those who do will not keep it
off. This will be correctly attributed to the University of
Pennsylvania psychiatrist Albert Stunkard, but it will go
unmentioned that this statement is based on 100 patients who
passed through Stunkard's obesity clinic during the Eisenhower
administration.
Some of the best scientists disagreed with this low-fat logic,
suggesting that good science was incompatible with such leaps of
faith, but they were effectively ignored. Pete Ahrens, whose
Rockefeller University laboratory had done the seminal research
on cholesterol metabolism, testified to McGovern's committee
that everyone responds differently to low-fat diets. It was not
a scientific matter who might benefit and who might be harmed,
he said, but ''a betting matter.'' Phil Handler, then president
of the National Academy of Sciences, testified in Congress to
the same effect in 1980. ''What right,'' Handler asked, ''has
the federal government to propose that the American people
conduct a vast nutritional experiment, with themselves as
subjects, on the strength of so very little evidence that it
will do them any good?''
Nonetheless, once the N.I.H. signed off on the low-fat doctrine,
societal forces took over. The food industry quickly began
producing thousands of reduced-fat food products to meet the new
recommendations. Fat was removed from foods like cookies, chips
and yogurt. The problem was, it had to be replaced with
something as tasty and pleasurable to the palate, which meant
some form of sugar, often high-fructose corn syrup. Meanwhile,
an entire industry emerged to create fat substitutes, of which
Procter & Gamble's olestra was first. And because these
reduced-fat meats, cheeses, snacks and cookies had to compete
with a few hundred thousand other food products marketed in
America, the industry dedicated considerable advertising effort
to reinforcing the less-fat-is-good-health message. Helping the
cause was what Walter Willett calls the ''huge forces'' of
dietitians, health organizations, consumer groups, health
reporters and even cookbook writers, all well-intended
missionaries of healthful eating.
Create an obesity epidemic and of course businesses are going to
jump on the money-making machine of trying to end it (and end up
making it worse, of course, contributing to the obesity epidemic
while touting all they are doing to supposedly end it).
Few experts now deny that the low-fat message is radically
oversimplified. If nothing else, it effectively ignores the fact
that unsaturated fats, like olive oil, are relatively good for
you: they tend to elevate your good cholesterol, high-density
lipoprotein (H.D.L.), and lower your bad cholesterol,
low-density lipoprotein (L.D.L.), at least in comparison to the
effect of carbohydrates. While higher L.D.L. raises your
heart-disease risk, higher H.D.L. reduces it.What this means is
that even saturated fats -- a k a, the bad fats -- are not
nearly as deleterious as you would think. True, they will
elevate your bad cholesterol, but they will also elevate your
good cholesterol. In other words, it's a virtual wash. You will
gain little to no health benefit by giving up milk, butter and
cheese and eating bread instead.
The crucial example of how the low-fat recommendations were
oversimplified is shown by the impact -- potentially lethal, in
fact -- of low-fat diets on triglycerides, which are the
component molecules of fat. By the late 60's, researchers had
shown that high triglyceride levels were at least as common in
heart-disease patients as high L.D.L. cholesterol, and that
eating a low-fat, high-carbohydrate diet would, for many people,
raise their triglyceride levels, lower their H.D.L. levels and
accentuate what Gerry Reaven, an endocrinologist at Stanford
University, called Syndrome X. This is a cluster of conditions
that can lead to heart disease and Type 2 diabetes.
It took Reaven a decade to convince his peers that Syndrome X
was a legitimate health concern, in part because to accept its
reality is to accept that low-fat diets will increase the risk
of heart disease in a third of the population. ''Sometimes we
wish it would go away because nobody knows how to deal with
it,'' said Robert Silverman, an N.I.H. researcher, at a 1987
N.I.H. conference. ''High protein levels can be bad for the
kidneys. High fat is bad for your heart. Now Reaven is saying
not to eat high carbohydrates. We have to eat something.''
Yeah, we do have to eat something. How about a balanced diet of
meats, fats, nuts, seeds, fruits, veggies, and dairy? One that
doesn't rely on a food pyramid that doesn't have a clue (or
care) how it really affects people's health.
There is a lot more information in the article, but you can read
it yourself .
The full article can be read here:
http://query.nytimes.com/gst/fullpage.htmlres=9F04E2D61F3EF934A35754C0A9649C8B63&sec=health.
Gary taubes is the author of the book "good calories bad
calories" which received the following review from Richard
Rhodes, winner of the Pulitzer Prize
“Gary Taubes's Good Calories, Bad Calories is easily the most
important book on diet and health to be published in the past
one hundred years. It is clear, fast-paced and exciting to read,
rigorous, authoritative, and a beacon of hope for all those who
struggle with problems of weight regulation and general
health--as who does not? If Taubes were a scientist rather than
a gifted, resourceful science journalist, he would deserve and
receive the Nobel Prize in Medicine.”
Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat
Diet
Background Trials comparing the effectiveness and safety of
weight-loss diets are frequently limited by short follow-up
times and high dropout rates.
Methods In this 2-year trial, we randomly assigned 322
moderately obese subjects (mean age, 52 years; mean body-mass
index [the weight in kilograms divided by the square of the
height in meters], 31; male sex, 86%) to one of three diets:
low-fat, restricted-calorie; Mediterranean, restricted-calorie;
or low-carbohydrate, non–restricted-calorie.
Results The rate of adherence to a study diet was 95.4% at 1
year and 84.6% at 2 years. The Mediterranean-diet group consumed
the largest amounts of dietary fiber and had the highest ratio
of monounsaturated to saturated fat (P<0.05 for all comparisons
among treatment groups). The low-carbohydrate group consumed the
smallest amount of carbohydrates and the largest amounts of fat,
protein, and cholesterol and had the highest percentage of
participants with detectable urinary ketones (P<0.05 for all
comparisons among treatment groups). The mean weight loss was
2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet
group, and 4.7 kg for the low-carbohydrate group (P<0.001 for
the interaction between diet group and time); among the 272
participants who completed the intervention, the mean weight
losses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The
relative reduction in the ratio of total cholesterol to
high-density lipoprotein cholesterol was 20% in the
low-carbohydrate group and 12% in the low-fat group (P=0.01).
Among the 36 subjects with diabetes, changes in fasting plasma
glucose and insulin levels were more favourable among those
assigned to the Mediterranean diet than among those assigned to
the low-fat diet (P<0.001 for the interaction among diabetes and
Mediterranean diet and time with respect to fasting glucose
levels).
Conclusions Mediterranean and low-carbohydrate diets may be
effective alternatives to low-fat diets. The more favourable
effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that
personal preferences and metabolic considerations might inform
individualized tailoring of dietary interventions.
For the full study go to: http://content.nejm.org/cgi/content/full/359/3/229
Study surprise: Low-carb dieters eat more, lose weight
The dietary establishment has long argued it's impossible, but a
new study offers intriguing evidence for the idea that people on
low-carbohydrate diets can actually eat more than folks on
standard lowfat plans and still lose weight.
Perhaps no idea is more controversial in the diet world than the
contention -- long espoused by the late Dr. Robert Atkins --
that people on low-carbohydrate diets can consume more calories
without paying a price on the scales.
Over the past year, several small studies have shown, to many
experts' surprise, that the Atkins approach actually does work
better, at least in the short run. Dieters lose more than those
on a standard American Heart Association plan without driving up
their cholesterol levels, as many feared would happen.
Sceptics contend, however, that these dieters simply must be
eating less. Maybe the low-carb diets are more satisfying, so
they do not get so hungry. Or perhaps the food choices are just
so limited that low-carb dieters are too bored to eat a lot.
Now, a small but carefully controlled study offers a strong hint
that maybe Atkins was right: People on low-carb, high-fat diets
actually can eat more.
The study, directed by Penelope Greene of the Harvard School of
Public Health and presented at a meeting here this week of the
American Association for the Study of Obesity, found that people
eating an extra 300 calories a day on a very low-carb regimen
lost just as much during a 12-week study as those on a standard
lowfat diet.
Over the course of the study, they consumed an extra 25,000
calories. That should have added up to about seven pounds. But
for some reason, it did not.
"There does indeed seem to be something about a low-carb diet
that says you can eat more calories and lose a similar amount of
weight," Greene said.
A calorie just a calorie?
That strikes at one of the most revered beliefs in nutrition: A
calorie is a calorie is a calorie. It does not matter whether
they come from bacon or mashed potatoes; they all go on the
waistline in just the same way.
Not even Greene says this settles the case, but some at the
meeting found her report fascinating.
"A lot of our assumptions about a calorie is a calorie are being
challenged," said Marlene Schwartz of Yale. "As scientists, we
need to be open-minded."
Others, though, found the data hard to swallow.
"It doesn't make sense, does it?" said Barbara Rolls of
Pennsylvania State University. "It violates the laws of
thermodynamics. No one has ever found any miraculous metabolic
effects."
In the study, 21 overweight volunteers were divided into three
categories: Two groups were randomly assigned to either lowfat
or low-carb diets with 1,500 calories for women and 1,800 for
men; a third group was also low-carb but got an extra 300
calories a day.
The study was unique because all the food was prepared at an
upscale Italian restaurant in Cambridge, Massachusetts, so
researchers knew exactly what they ate. Most earlier studies
simply sent people home with diet plans to follow as best they
could.
Each afternoon, the volunteers picked up that evening's dinner,
a bedtime snack and the next day's breakfast and lunch. Instead
of lots of red meat and saturated fat, which many find
disturbing about low-carb diets, these people ate mostly fish,
chicken, salads, vegetables and unsaturated oils.
"This is not what people think of when they think about an
Atkins diet," Greene said. Nevertheless, the Atkins organization
agreed to pay for the research, though it had no input into the
study's design, conduct or analysis.
Raising questions
Everyone's food looked similar but was cooked to different
recipes. The low-carb meals were 5 percent carbohydrate, 15
percent protein and 65 percent fat. The rest got 55 percent
carbohydrate, 15 percent protein and 30 percent fat.
In the end, everyone lost weight. Those on the lower-cal, low-carb
regimen took off 23 pounds, while people who got the same
calories on the lowfat approach lost 17 pounds. The big
surprise, though, was that volunteers getting the extra 300
calories a day of low-carb food lost 20 pounds.
"It's very intriguing, but it raises more questions than it
answers," said Gary Foster of the University of Pennsylvania.
"There is lots of data to suggest this shouldn't be true."
Greene said she can only guess why the people getting the extra
calories did so well. Maybe they burned up more calories
digesting their food.
Dr. Samuel Klein of Washington University, the obesity
organization's president, called the results "hard to believe"
and said perhaps the people eating more calories also got more
exercise or they were less apt to cheat because they were less
hungry.
"http://edition.cnn.com/2003/HEALTH/diet.fitness/10/14/lowcarb.mystery.ap/
LOW CARB DIETS COMBAT METABOLIC SYNDROME:
http://www.forbes.com/forbeslife/health/feeds/hscout/2007/07/20/hscout606585.html
LOW CARB DIETS IMPROVE
CHOLESTEROL EVEN WITHOUT WEIGHT LOSS:
Often when diets are compared, especially when weight loss is
involved, it’s hard to tell if changes in health indicators
(such as blood pressure or triglycerides) are due to the diet
itself or the resulting weight loss. This study from Ronald
Krauss and his colleagues attempts to address this issue.
Four groups of men eating different carbohydrate levels and
different levels of saturated fat were followed for changes in
blood lipids (cholesterol and triglycerides). First, they all
ate the same diet, then they were divided into the different
diet groups -- first without weight loss, then with reduced
calories.
Overall results:
The low-carb groups improved on most of the parameters of
cholesterol and triglycerides, even without weight loss. With
weight loss, there was further (but smaller) improvement in the
low-carb groups, and the high carb group partially caught up,
but not all the way. These trends included LDL particle size,
with the low-carb groups going in the “good” direction.
Additionally, the group that was higher in saturated fat had the
greatest increase in particle size. Most of the changes with the
“medium carb” diet were intermediate between the higher and
lower carb diets. On a calorie intake designed to keep weight
stable, the low-carb groups still lost weight.
http://lowcarbdiets.about.com/od/science/a/lowcarbcholest.htm
|
|
|
 |
