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Some
Valid Points But Several Crucial Oversights and Misconceptions
A
Review by Joel Kauffman, PhD (kauffman37@yahoo.com)
 With
a prolific talent for writing that gets him published in USA
Today, Harper’s Magazine, and the Los Angeles Times,
among others, Greg Critser has produced an easy-to-read, well-edited,
and highly entertaining expose of the fattening of America
called Fat
Land: How Americans Became the Fattest People in the World.
(Houghton Mifflin Co., Boston, MA, 2003.)
Unfortunately, this "fat tale" is missing a good
part of the meat.
A number of unsurprising trends are highlighted and their
origins uncovered. Among the valid culprits cited are increasing
portion sizes at fast food chains and in soft drinks; the
pollution of school cafeterias with junk food; and the use
of high-fructose corn syrup to sweeten and thicken almost
everything under the sun. TV commercials and other food ads
aimed at children come in for their fair share of blame as
well.
But these valid points are accompanied by a litany of oversights
and misconceptions that detract from the book’s overall
value.
The
Sweet Truth
For example, one of Critser’s more glaring blunders
is the very important omission that simple sugars and starches
as well do nearly all the damage leading to obesity and also
to type 2 diabetes as well.
Unfortunately, the notion of the Glycemic Index (GI), now
more than 80 years old, never entered Critser’s mind.
The GI of a food is measured by checking blood glucose levels
after eating. The GI of a food shows the % glucose levels
rise compared with the same weight of glucose, with the glucose
benchmark having a GI of 100.
The primary cause of high insulin levels, and the insulin
resistance that results, is high blood glucose levels. Since
all the common complex carbohydrates (starches/refined grains)
are polymers of glucose, and many of them are metabolized
very rapidly into glucose, and we eat more of them by weight,
the contribution of wheat, corn, potato and other forms of
high-GI starches to poor health is greater than that of many
of the simple sugars.
The so-called "low-carb" diets must be low GI diets
to be effective, and they really are effective for weight
loss and the prevention of type 2 diabetes, because blood
sugar levels are kept in check (Bernstein 1997, Ottoboni 2002).
In addition to the fact that the low-carb diets are by default
lower GI diets, fat makes the stomach empty more slowly and
slows down digestion, thus keeping the blood glucose concentrations
lower by blunting or smoothing out the glucose rise (Enig
2000).
Critser’s lack of knowledge about this simple concept
is not suprising, however, and he can almost be forgiven for
it, since the ignorance is shared by many "experts"
including the American Diabetes Association, and many others.
However, this is not his only blunder.
Bashing
the Low-Carb Diets
His misconception about the importance of the GI relates
somewhat to another blunder, which is the claim that the Atkins
diet and other low-carb diets (The
No-Grain Diet by Dr. Mercola was not yet published at
the time Critser’s book was written) are inherently dangerous.
This is partly because of Critser’s false representation
that unlimited calories are recommended or allowed. Not only
are there caloric intake guidelines with most low-carb diets,
certainly those of Bernstein and Eades, the fact is that people
following such a diet will almost always consume fewer calories,
due to the fact that fat is better at achieving satiety, or
the feeling of fullness, than carbs are. The usual sensible
recommendation is for 40% or fewer calories from low-GI carbohydrates,
30% from fats, and 30% from proteins (Eades 2000, McGee 2001,
Ottoboni 2002).
This error was accompanied by the blunder that all carbohydrates
were supposedly eliminated, including the ones with very low
GI, such as vegetables and fruits. Nearly all non-root vegetables
have very low GI’s and even many fruits (e.g., cherries,
berries, citrus) have GI’s well below those of refined
grains.
Although usually unsuccessful, especially in the long-term,
the occasional weight loss success of people on low-fat diets
such as those promoted by Drs.Whitaker, Pritikin and Ornish
may be due to lower total calories or the many lifestyle changes
were made in addition to diet (exercise, stress reduction,
etc), or possibly the elimination of bad fats, such as trans
and omega-6, or oxidized fats.
As it happens, clinical trials have shown that low GI diets
are the only ones most people can maintain. And what good
is a diet anyway, if it can’t be maintained?
The
Cholesterol Myth
On the same plane in "Blunderland", Critser also
succumbed to what very likely is the biggest fraud in the
history of medicine: that eating saturated fat and cholesterol
causes obesity and/or clogged arteries and heart disease (p15,140).
This nonsense was promulgated by a campaign by the American
Heart Association (AHA) begun in 1961, and its anti-cholesterol,
pro-polyunsaturated fat campaign, which peaked in the 1980s
but is still widely accepted, despite the mountain of evidence
against it.
The actual data in the widely touted Framingham study, or
any other honest study for that matter, actually contradicts
this anti-fat stand, despite the politically correct abstracts
or summaries of many of the studies. (Moore 1989, Smith 1991,
Fehily 1993, Fraser 1997, Tunstall-Pedoe 1997, Eades 2000,
Enig 2000, Kauffman 2000, Kauffman 2001, McCully 2000, McGee
2001, Ottoboni 2002, Ravnskov 2000).
The full refutation of the "Lipid Hypothesis",
as it is commonly known in medical circles, is beyond the
scope of this review. For more extensive information on this
subject, see the website of The International Network of Cholesterol
Skeptics (www.thincs.org).
Bad
Fats
Another major blunder is Critser’s failure to properly
identify what a "bad fat" is. Not even a word is
uttered about avoiding trans fats, as though the ill-health
effects of them were still in doubt (Willett 1993, Oomen 2001).
Even the AHA began to warn about trans fats in 2002.
Speaking of "bad fat", Critser’s dump on palm
oil is totally unfounded, based on actual cohort studies,
which show just the opposite (Wood 1993, Enig 2000).
Another shortcoming of Critser’s book is that he fails
to discuss the issue of essential fatty acids and the current
imbalance of omega-6 and omega-3 fatty acids in the diet.
There was no mention that omega-6 is over-consumed, in the
form of corn, soy and vegetable oils (Enig 2000, Vos 2003),
nor was there much on eating the good omega-3 fats which are
deficient in Western diets when ocean fish are not consumed
(Vos 2003).
Exercise
Nobody really disputes the importance of exercise, but Critser
goes a little too far. For example, on recent immigrants to
the US, Critser states "When new immigrants were asked
whether rest was more important or better for health than
exercise, a large portion ‘always says yes’. The
attitude was doubly corrosive...".
Critser seems not to be able to comprehend that most new
immigrants do hard manual labor in their employment, and they
are correct to choose rest.
His unquenchable recommendations for exercise have some merit
(Bernstein 1997), but the only prospective, randomized study
of exercise after heart attack found only a slight benefit
of exercise on cardio-vascular mortality for the first few
years, disappearing at 5 years (Dorn 1999).
Body
Mass Index
Critser fell for the nonsense that being leaner is always
better and leads to longer life. One of the best studies ever
conducted found that in both men and women, the relation between
weight or body mass index (BMI) and heart deaths or all-cause
deaths was U-shaped, not inverse; that is, those of middle
weight and middle BMI lived the longest (Tunstall-Pedoe 1997).
And so it was also with energy intake (Fehily 1993, Tunstall-Pedoe
1997).
Conclusion
As I said at the outset, Critser is an excellent writer and
I’ll give him the benefit of the doubt that he truly
means well. He does take great pains to outline steps that
can be taken to help relieve the obesity epidemic in the US.
However, even if the reforms he recommends were implemented,
my guess is that only about 1/3 of the obesity problem in
the US would be alleviated. I suppose any improvement would
be most welcome in light of the extent of the current problem.
However, due to the numerous shortcomings, I’m reluctantly
forced to bestow upon it a rating of only 2 stars on a scale
of 1-5 stars.
For further information on many of the subjects discussed
above, see www.THINCS.org
Joel
M. Kauffman, Ph. D., Professor of Chemistry Emeritus, University
of the Sciences in Philadelphia (email - kauffman37@yahoo.com)
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