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Good Calories Bad Calories Review
The Practical Scientist 7 By Jamie Hale
Key Points from Good Calories Bad Calories Gary Taubes; New York: AA Knopf (Bray 2008).
“Good Calories, Bad Calories is a scholarly book that
musters the evidence for the case against the high-fat
hypothesis for heart disease, cancer and obesity and in
favour of the carbohydrate-insulin hypothesis. The bibliography
is robust and contains a wealth of information.
The book begins with Mr William Banting and the diet
he published in 1863 as a small pamphlet called ‘A Letter
on Corpulence Addressed to the Public’. In this pamphlet,
Banting described his dietary success with a low carbohydrate
diet. The hostility that Mr. Banting aroused
among the ‘medical establishment’ in the 1860s is reminiscent
of some of the comments about popular diets that have
come from the ‘medical establishment’ in the last half of
the 20th century.
The background work on energy expenditure
in human beings from Antoine Lavoisier, Hermann Helmholtz,
Robert Mayer Carl Voit, Max Pettenkoffer, Max
Rubner and Wilbur Atwater is very nicely detailed by Mr
Taubes. In addition to these, there are many other descriptions
of scientists and their work that make this book
particularly fascinating to read.
Good Calories, Bad Calories is divided into three main
parts. The first part is a critique of the Diet-Heart hypothesis,
and the idea that dietary fat was the principal culprit
in the rising incidence of heart disease during the 20th
century. From an analysis of published data and discussion
with many leaders, Taubes concludes that the Diet-Heart
hypothesis detracted from our understanding of the relation
of diet to heart disease. As Taubes sees it, Ancel Keys
played the role of major villain in selling the idea
The second part of Good Calories, Bad Calories sets
forth the ‘carbohydrate hypothesis’. This hypothesis is
Taubes’s basis for explaining the evils of the ‘nutrition
transition’ that have afflicted countries moving from their
traditional diets to the Western type of high-fat, high-sugar,
high-salt diet.
In the third part of Good Calories, Bad Calories, called
the ‘Mythology of Obesity’, the author argues that the
energy-balance equation does not adequately explain
obesity because obese people do not eat more than lean
ones, and because they can lose weight eating a large
number of calories, provided that the calories are very low
in carbohydrates – that is, high in protein and fat.
In the section on ‘The Mythology of Obesity’ and the
carbohydrate-insulin hypothesis, there is no mention of
doubly labelled water, a sophisticated technique that has
allowed us to ‘check’ on the accuracy of self-reports of food
intake. Also missing is a discussion of the ‘nutrient’ balance
hypothesis. These limitations may change the conclusions
that are reached from reading Good Calories, Bad
Calories.
Critique of Good Calories, Bad Calories
One summer I admitted a group of four overweight teenagers
to our clinical research unit at the Harbor UCLA
Medical Center and put them on a 1000-cal diet under
direct observation. As expected, all of the girls lost weight
and were delighted with the result. When they left at the
end of the summer, one of the girls, who lived only a short
distance from the hospital, wanted to come back to see us
so she could continue to lose weight. We instructed her on
how to keep a food diary. When she returned 2 weeks later,
she had gained a few pounds. She showed us her diary,
which was very neatly and carefully kept. The average daily
food intake was about 300–400 kcal d-1. As she had lost
weight eating 1000 kcal d-1 while directly observed in the
hospital, we were sceptical of the accuracy of her outpatient
recording. We instructed her again on keeping food
records. She returned after another 2 weeks, having gained
even more weight and with records still showing she only
ate 300 kcal d-1 or so. There was an obvious discrepancy,
reflecting the difficulty of keeping reliable records. It was
thus clear that this girl was either kidding herself or trying
to kid us about how much she was eating. We have subsequently
had the opportunity to study weight loss in a
number of subjects in both the metabolic unit and then on
similar diets in an outpatient setting. Weight loss under
observation is about 50% faster than with the equivalent
‘prescribed’ energy deficit in an outpatient setting. The
difference is adherence to or compliance with the diet.
Obesity is the result of a prolonged small positive energy surplus with
fat storage as the result. An energy deficit produces weight
loss and tips the balance in the opposite direction from
overeating.”
Comments from Taubes Responses from Bray
Comment: “The problem is the carbohydrates in the diet, their effect on insulin
secretion, and thus the hormonal regulation of homeostasis – the
entire harmonic ensemble of the human body. The more easily
digestible and refined the carbohydrates, the greater the effect on
our health, weight and well-being.
Response: The problem is a positive energy balance persisting over an extended
period of time, which may be exacerbated by high-fructose/high-fat
foods and other environmental agents acting on genetically
susceptible individuals.
Comment: Through their direct effect on insulin and blood sugar, refined
carbohydrates, starches and sugars are the dietary cause of
coronary heart disease and diabetes. They are the most likely
dietary causes of cancer, Alzheimer’s disease, and the other
chronic diseases of civilization.
Response: There is no convincing evidence that carbohydrates are producing
cancer, Alzheimer’s disease, type 2 diabetes, or coronary artery
disease.
Comment: Obesity is a disorder of excess fat accumulation, not overeating,
and not sedentary behaviour.
Response: Obesity is the result of a small positive energy balance occurring over
time. The Laws of Conservation of Energy (First Law of
Thermodynamics) do not tell us why this imbalance occurs.
Comment: Consuming excess calories does not cause us to grow fatter any
more than it causes a child to grow taller. Expending more energy
than we consume does not lead to long-term weight loss; it leads to
hunger.
Response: Consuming excess calories routinely produces obesity, and consuming
fewer calories than your body needs produces weight loss.
Comment: Fattening and obesity are caused by an imbalance – a
disequilibrium – in the hormonal regulation of adipose tissue and fat
metabolism. Fat synthesis and storage exceed the mobilization of
fat from the adipose tissue and its subsequent oxidation. We
become leaner when the hormonal regulation of the fat tissue
reverses this balance.
Response: Fat accumulation cannot occur without caloric intake exceeding
expenditure. Fat deposits differ in their health risks: visceral fat is
strongly related to heart disease and diabetes; subcutaneous
abdominal fat much less so; and fat on the legs may be ‘protective’.
These differences in fat locations partly determine the differences in
life expectancy between men and women.
Comment: Insulin is the primary regulator of fat storage. When insulin levels
are elevated – either chronically or after a meal – we accumulate fat
in our fat tissue. When insulin levels fall, we release fat from our fat
tissue and use it for fuel.
Response: Insulin is needed for fat storage, but it is for the purpose of storing the
‘extra’ calories not needed for daily energy expenditure. Chronic
elevation of insulin, as in insulinoma, has only a modest effect on
weight – something else is needed for ‘obesity’ in addition to insulin.
Comment: By stimulating insulin secretion, carbohydrates make us fat and
ultimately cause obesity. The fewer carbohydrates we consume, the
leaner we will be.
Response: Calories count. Fructose (HFCS or sugar) plus a modest- or high-fat
diet enhance the risk of overpowering the homeostatic feedback
system.
Comment: By driving fat accumulation, carbohydrates also increase hunger
and decrease the amount of energy we expend in metabolism and
physical activity.
Response: The quantity of fat we eat in a day is less than 0.5% of the fat we have
stored, and these changes in fat deposition do not lead to increased
appetite, as they are hardly seen on the concentration of leptin and
other adipose tissue-related peptides.”
My thoughts
I enjoyed the review. I liked the comment and response section of the paper the most. I have read reviews from various authors on this book and they all conclude that the book contains some good reading but also contains much NONSENSE.
The key messages that Taubes promotes are nothing new. Many nutrition authors have suggested insulin causes obesity, calories don’t really matter, and carbohydrates make you fat and so on. Many of the readers of popular nutrition books seem to like the idea that there is something more to it than calories. They can’t believe what Primary Researchers have been telling them for years- CALORIES DO MATTER. Many book readers enjoy science fiction. Should we expect different when it comes to nutrition books?
References
G. A. Bray (2008) Good Calories, Bad Calories by Gary Taubes; New York: AA Knopf
Obesity Reviews 9 (3) , 251–263.
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Jamie Hale | Mind and Muscle
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