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Fad Diet Follies
Why Atkins and his
ilk are for suckers
–
How is that low-carb diet working out for you? Perhaps you are on a low-fat diet, or you may be using a meal-substitution plan, going to a support group, or taking a dieting supplement. By now it's no news flash that Americans are fat, and we are getting fatter. Two thirds of Americans are overweight or obese, and this new epidemic is spreading to every demographic, even the young.
In the last few decades, the "weight-loss industry" has been bulging right along with the American waistline, with a plethora of products and plans catering to the desperately chunky. Despite the widespread use of diet plans and supplements, Americans have continued to grow larger, with a subsequent increase in diseases related to weight, like heart disease and diabetes.
There is plenty of blame to go around, and the American lifestyle is first in line. Americans are more sedentary than ever, glued to their TVs and computers and spending less time in physical activity. We also eat more: Americans have a legendarily gluttonous, positively supersized diet. Both sedentary time and food-portion sizes have increased, as Americans get predictably fatter despite bookstore shelves filled with weight-loss self-help books.
But it seems reasonable to put a portion of the blame on the weight-loss
industry itself, which fools people with bad advice and products that simply do
not work. The problem is that the advice and products peddled to consumers are
not in line with the scientific advances that have been made in nutrition and
weight loss over this same period. In the marketplace, pseudoscience tends to
prevail, offering simple answers to complex questions--and easy, quick fixes to
hard problems. What
The scientific secret to successful weight loss and long-term weight control is...eat less and exercise more! That's it. There is an unavoidable formula that determines our weight--calories in versus calories out. Calories are simply a measure of energy, and we get our energy from the fat, protein, and carbohydrates (sugars) in our food. We store most of our excess energy in body fat (and some in protein and carbohydrates). Our bodies burn calories to carry out basic life-sustaining functions and to perform physical activities. Your weight is therefore ultimately a function of math--subtract the calories you burn from the calories you eat, and that is how many calories (therefore how much fat) you have gained or lost.
The problem with most weight-loss fad diets is that they ignore or minimize
this fundamental, inescapable truth. They emphasize instead the types of
calories that are eaten--fat, protein, or glucose. The Atkins,
To make matters worse, the mainstream media outlets and promoters of specific diets have done a poor job of getting accurate information to consumers. During the Atkins craze, many were quick to hype that studies have shown that the low-carb diet "works." What those studies actually showed is that weight loss was very modest and related directly to total caloric intake. Low-carb diets do seem to be related to less hunger, and therefore less eating, but this effect is modest and short-term, lasting only three to six months. There is no study showing a long-term advantage to a low-carb (or any particular) diet.
And that brings up the other major point missed by the fad-diet promoters--short-term advantages or effects are meaningless. What we need are strategies for long-term sustained weight control. Fad diets almost always fail in the long run, because most people find the monotony unsustainable. People want their fat and carbs.
It's time for Americans to face the ugly truth: There are no easy weight-loss miracles out there. Weight management is hard work. You have to be aware of what and how much you are eating, eat less than you may want or are used to, monitor your weight, and get regular exercise. We have to shed the nonsense before we can shed the pounds.
Letters and Dr. Novella’s Responses
Letter 1
Howdy
Atkins has been around way to long to call it a fad. It wasn't widely accepted,
but it was around over 30 years.
I lost over 80 pounds on Atkins in about a year. Near the end of that, I found
out I have Congestive Heart Failure. No, not from Atkins, my Dad had the same
thing at about the same age. On the other hand, I have less than 10 percent
blockage, so a year on Atkins didn't hurt.
A few years ago, I had a massive tooth infection and became so weak I could
barely walk to the other end of the house. At the time I was about 20 pounds
overweight, exercising, and could go about an hour and 20 minutes at my target
pulse rate. A few days later I couldn't stand long enough to take a shower
without exhaustion and considerable pain in my legs. I stayed that way
for a few YEARS. After I read the Atkins book, I started limiting my Carbs, and as it kicked in, I had a considerable increase
in my strength in a short time. I was in Ketosis. Something about that started
me back towards normal strength, and health.
My sister saw me before Atkins and after, (she's a Nurse Practitioner) and she
says the Congestive Heart Failure probably would have killed me if I hadn't
been on Atkins. Since you wrote an article about it, I suppose you at least one
of the Atkins books.
The part about Ketosis is important. I didn't count calories, I just limited Carbs. Days when I felt hungry, I had Bacon, chunks of
cheese, and other Low Carb snacks. DIDN'T go hungry.
Stayed in Ketosis, and lost weight. My biggest problem was that I sometimes
didn't eat as many Carbs as I was supposed to.
It's not just Calories in and out. Ketosis helps burn FAT. I
didn't lose much muscle as far as I can tell. I didn't have the resources
to measure body fat, but I didn't lose much.
And I'll be honest, in the last year, I gained about 20 back, but I was in the
Hospital twice and my Dad died. It was a tough year. Try telling the Hospital
you want more meat and vegetables but fewer Carbs.
They just don't believe in changing things. I'm back limiting my Carbs now, the pants seem loser, and I feel better (partly
due to the Pacemaker they put in).
Ketosis puts your body into a different "state of mind", it starts
burning more fat. Which of course means it actually is burning more calories,
in a sense. Wasting more too, but I got 'em to spare.
There have been several studies cited the last couple of years that say it
works. But, when it comes to me, I'm fairly anecdotal. For me, it worked great,
and probably saved my life. It's been around 30 years, and several new studies
say it works well, so maybe "fad" isnt' the
best way to describe it. And I think it's dangerous to lump all approaches
together, maybe some work and some don't.
Thanks, Have Fun.
Dennis Lucus Jr
Dr. Novella’s Response:
Dennis,
Thanks for your note. I know I left a lot of specifics out of the article -
they only give me 800 words. So here is some clarification:
The term "fad" is used to refer to a diet with broad recommendations
for everyone - not necessarily a new or short-lived diet. I know Atkins has
been around for decades, but its surging popularity is recent and probably will
not last long, although the Atkins diet, I'm sure, will be around for awhile.
I have carefully reviewed the literature on Atkins and other diets. They show
that there is a short term advantage for hunger, but they also show the
following:
- weight loss during the studies was modest
- the advantage to hunger for low carbs was
temporary, apparently not lasting more than 6 months
- weight loss correlates with calorie intake. There has yet to be a single
study which shows that you can lose more weight at the same calories by just
lowering carbs. So, you were reducing your
calories even though you didn't realize it.
- most people on Atkins gain the weight back after a year or so. The 5-year
success rate is very low, and it is better on low-fat diets. However, the best
measure of long-term success is just reducing calories and exercising
regularly.
Ketosis is definitely part of an ultra-low carb diet,
but it is not a healthy condition to maintain. It hurts the brain, and in
extreme cases can even cause coma (diebetics can go
into a ketoacidodic coma if untreated). Ketosis is
not a safe and effective long term strategy for maintaining weight loss - and
long term is all that counts. At best, it is a short-term gimmick, but it often
motivates people to buy into the low-carb diet.
You should note that the dept. of agriculture just came out with their updated
guidelines, based upon a lengthy review of all available evidence by a panel of
experts - and they recommend to count calories, not carbs,
and to exercise regularly.
I know I lumped all diets together - I had to due to length constraints, but I
did focus on what they have in common. I don't think there is anything
dangerous about recommending reducing calories and exercising as a way to
maintain weight and good health; to focus on the long term, and not put
your faith in easy weight-loss schemes that the evidence shows have no long-term
advantage.
I hope this clarifies my position. Thanks again for your letter.
Regards,
Steven Novella
Letter 2
Dear Professor Novella:
I read with interest your article in the New Haven Advocate website. Your basic
premise is one with which the experts at the Pritikin
Longevity Center absolutely agree; when it comes to weight loss, the
fundamental law of calories-in versus calories-out is the gold standard.
But I feel that it is important that you understand another profoundly
important part of our program.
Pritikin's approach is to emphasize optimal health
and well being, with weight loss coming as a wonderful side effect of eating
and living according to our guidelines. (Our guidelines are, by the way, are
very similar to the new recently released USDA guidelines. It's nice to know
the USDA is finally coming around to what we have been teaching for the past 30
years.) We do not believe the goal should simply be weight loss. After all, as
that fundamental law implies, as long as you eat fewer calories than you
expend, you will lose weight even if the weight loss comes from eating 1,500
calories worth of junk food every day.
Our goal is to set nutritional guidelines that maximize people's health. Yes,
we want to help people lose weight, but we also want people to have clear
arteries and not suffer from diabetes, hypertension or heart disease. Unlike
other programs, we have published over 100 articles in the all the leading
peer-reviewed medical journals on the beneficial effects of our program on the 90,000
people that have been through our doors.
Knowing and respecting your expertise in nutrition, I would like to invite you
to chat with our experts in nutrition so that you can understand what we do. I
believe that you will find our approach to be one that is much more than just
"low fat" or a "fad diet" and one that you could not only
admire and tout...but also write about.
Best wishes,
Marika Olsen
Media Director
Dr. Novella’s Response:
Marika,
Thanks for your letter. The length of my Advocate article did not allow for a
detailed discussion of individual diets. I only had time to strike a basic
theme - calorie reduction and regular exercise are the key, not radical changes
in the food type. I wanted to get people to accept that weight loss is long-term
hard work, and forget about claims for easy or quick answers.
I restricted my focus to weight loss in the Advocate article, but you are, of
course, correct that heart health, diabetes, and overall nutritional must be
considered in assessing any diet, not just weight loss.
I agree that the literature shows, in general, low fat diets are better than
low carb diets, especially long term. However, most
of the literature specifically on Pritikin is fairly
short term (and I just reviewed the list of articles on your web page). The
long term studies are retrospective and look only at low-fat in general, not Pritikin specifically. One of the other points in my
article is that long term weight control and health is what's most important.
Getting healthy for 3 weeks is great, but can you maintain it. Most people
don't. Further, many of the studies are complicated by the fact that the
intervention also included exercise. It is possible that regular exercise was
the dominant, maybe even only, important factor in the improvements seen. There
aren't enough studies to separate out these variables, and those that due tend
to favor exercise as the key to long term success.
Actually, the program with the best evidence for long term success is Weight
Watchers, which also focuses on calorie reduction and regular exercise, but
seems to be the most successful in training people to have healthy habits long
term.
Also, at least early on, the Pritikin diet focused
more on total fat reduction and did not adequately focus on reducing
"bad" fat while maintaining "good" fat. Some of the
published studies that show a lowering of total cholesterol also showed no
change in the ratio of HDL to LDL. This may be due to the fact that good fat
was lowered too much in the Pritikin diet, but also
may be because the studies were too short term, and ratio changes come only
after longer intervention. Exercise, for example, should improve the ratio.
But, I acknowledge that the Pritikin focus on eating
vegetables and reducing red meat would tend to result in a good ratio of fat
intake, I still think there is an excessive and perhaps unnecessary focus on
reducing total fat. Perhaps the center has updated their recommendations in
light of new research. That would be a good thing.
So, I agree that the Pritikin diet in general is a
good one, certainly much better than the low carb
diets, and including exercise in the overall health program is good. However,
long term data on whether or not people can stick to the program is lacking and
I am not that impressed by short term results from intensive intervention. I
would like to see the popular diets converge more on current scientific data,
and emphasize calorie reduction and exercise more. I agree that some diets,
like Pritikin and Weight Watchers, are farther along
than others. There are also many meal replacement products that have evidence
to support their effectiveness as part of any overall weight loss program.
Thanks again. I hope this clarifies my position. I would welcome any references
or pdf's of published peer-reviewed research for my
files.
Regards,
Steve Novella