The World Turned Upside Down: The Second Low-Carbohydrate Revolution (5 page)

Wherever the idea came from, it was
wrong. Fat consumption,
if anything, went down during the obesity epidemic – almost all of the
increase
in calories was in carbohydrates. There is no evidence that there is
anything
wrong with saturated fat but if you don't like it, there are numerous
alternatives. Our understanding of carbohydrate as the control element
and fat
as a more passive passenger suggests that the combination of high
carbohydrate
and
high
fat will be a bad thing. But you don't want to try to be low-carb and
low-fat
unless you like feeling hungry. You may like the feeling and total
calorie
restriction has general health benefits but the
de facto
reduction in carbohydrate is
probably the controlling factor.

Doing low-carb: Give up
desert and sweets.

Reducing sugar is part of reducing
carbohydrate. For some people,
it may be all you need or at least enough to get you started.
It will be beneficial if you don't put
starch back in place of
the sugar that you remove.
The strange collection of
bedfellows
currently involved in the political movement that I call fructophobia,
the
attack on sugar, forgot to tell you that sugar is a carbohydrate. If
you cut
out sugar and replace it with "healthy" high-grain, high-carbohydrate
oatmeal,
you are stacking the cards against yourself. For many people cutting
out sugar
is easy but if you have a sweet tooth, you will need some help. One
strategy is
to imagine that you are conducting an experiment. The hypothesis from
anecdotal
observation is that cravings for sweets disappear in three days on zero
sweets.
Your experiment will test whether that is true for you.

If you have to have something sweet,
there are several
non-nutritive sweeteners, some natural, some artificial. You may want
to avoid
artificial sweeteners, especially in diet soda since they may sustain
your
taste for sweets and some people react poorly to them. The scare
stories about
the artificial sweeteners are not scientifically sound but the possible
effect
of "sweetness" may be real. Among the simple solutions if you don't
mind the
artificial sweeteners, are sour cream sweetened with sugar-free syrups.

You should do whatever works but I
think that, for most
people, it is probably better to avoid the mind-set pushed by many
nutritionists (reason enough to avoid it) that you are allowed treats,
or that
you are allowed a "cheat day." You are not "allowed" treats. Nobody's
perfect
and sweet things do taste good and you will have some. We all screw up
periodically and you have to just go back to the plan. Sweets are not
really
allowed in the sense of being a specific feature of your diet. Consumed
sweets
are, speaking scientifically, experimental error. There are people who
are able
to incorporate some sweets as part of their diet and don't deviate from
the
single ice-cream bar that they have every day as the lone large source
of
carbs. Some people can get away with it, and if you like food you will
certainly find certain foods that are worth the risk to your diet, but
they are
not "allowed" in the sense of a recommendation. There is a big
difference
between the attitude that you can't be perfect and you will deviate
sometime
and the attitude that you deserve an occasional treat. On the other
hand, you
don't want to indulge in guilt feelings or mentally beat yourself up.
The
psychologist Alfred Adler always advised: do the wrong thing or feel
guilty but
not both.

The current hysteria about sugar may
help you cut back but
there is great danger in characterizing things as forbidden fruit, as
our very
earliest history shows. Especially if they want to ban it. Telling you
that you
can't have it may make it more appealing and when you see the absurd
lengths
that the media and researchers alike go to in order to demonize sugar,
you may
begin to think it is safe. Among lawyers, this is called "The Reverse
Mussolini" fallacy: Just because Mussolini made the trains run on time
doesn't
mean you want them to be unpredictable. (The last time I was in Italy,
the
trains did run on time, contrary to the Italian stereotype). Just
because the
USDA says it's bad, doesn't mean it's good.

Doing low-carb: Fruit
and other tricky foods.

All fruits have sugar and it is best
to apply the rule: eat
to the meter. If it doesn't interfere with weight loss or blood sugar,
or
whatever your goal is, then it is okay. I like Suzanne Somers'
technique
[19]
. Unlike many
"experts" who may be thin themselves –
what does Walter Willett know about fighting fat? – she lost a part in
Starsky and
Hutch
because
they told her she was "a little too chunky." She recommends eating
fruit in pieces;
half an apple now, the other half later. The goal is to avoid insulin
spikes.

Mike and Mary Dan Eades, authors of
Protein Power [17] ran a
clinic for many years. They had thousands of patients on low-carb
diets.
Despite generally great success, they had several patients who
complained that
they had faithfully adhered to the diet but were not losing weight. The
Eades
found that the three most common foods that caused trouble were cheese,
nuts
and nut butters; when these were reduced or removed from the diet,
patients
were able to continue to lose weight. Cheese is probably a simple
matter of
overconsumption; everything increased during the epidemic of obesity
and
diabetes – sugar, bread, fruits and vegetables – the only things that
went down
were red meat and eggs. One anomaly is that cheese consumption was off
the
chart. So, although apparently safe, moderation must be applied to
cheese. Dr.
Atkins recommended
[20]
that you restrict yourself to
hard cheese, which pretty much means serious cheese of the type in the
gourmet
cheese-shop. The greater intensity may be more satisfying but beyond
that, it's
not obvious why. Almost none of the cheeses in the supermarket qualify
as
serious cheese. The current price of good cheese, e.g. aged (at least 2
or 3
years) Gouda) also insures moderation for most of us.

Doing low-carb: "Not
license to gorge."

The phrase appears in the original
Atkins book several times
[20]. The idea is that whereas there are no stated limits on what you
can eat
if you keep carbohydrate low, overeating is not encouraged. The
principle that
"a calorie is a calorie" is not correct but calories do count and if
you are
concerned about your weight, you undoubtedly already know that it is
possible
to defeat any diet. The nutritionists are actually right about eating
slowly
(nobody's perfect). Satiety sets in slowly. A possible exception is
what to do
if you feel that you have the kind of cravings that will set your
low-carb diet
back. It may be useful to eat something that's allowed even if it seems
like
overeating. Some high protein, high fat food (if you have an Eastern
European
butcher, real kielbasa is best). Eventually, your cravings will
stabilize. In
general, the corollary to
Rule 1
of the General
Rules, is that if you have to overeat, don't overeat carbs.

Definitions

There are many variations of diets
based on carbohydrate
restriction. In diabetes, the principle is to keep carbohydrate as low
as
possible. In less stringent conditions, there may be more room for
maneuvering.
If specific diets are referred to,
Table
1-1
provides guidelines that should be used because they have been
published in
more than one peer-reviewed journal by people with the credentials and
experience.

The definitions are important.
Authors in the nutritional
literature give themselves license to call anything that they want a
low-carbohydrate diet. With a straw man in hand, it is not hard to show
that a
low-carbohydrate diet is dangerous to your health but the results do
not bear
on anything real.

Depending on your goal and who you
are, you may find a
graded response: the greater the carbohydrate reduction, the greater
the weight
loss, the greater the improvement in blood glucose, etc. Particularly
in weight
loss, however, there may be a threshold effect. The onset of ketosis,
which for
most people occurs at a daily intake of about 30g, will have a more
dramatic
effect.

Table 1-1.
Operational definitions of
carbohydrate restricted diets.

Summary

Three simple rules give you a good
guide to action. You are
the master of your diet. If you are not fat, if you don't have a health
problem
or a family history of disease, you probably are doing fine.
Low-carbohydrate
diets are primarily therapeutic and are the best for diabetes and
metabolic
syndrome. The evidence, both anecdotal and experimental, says that
nothing is
better for weight loss. To make it happen, eat to the meter, that is,
go for
results.

Two reasons for choosing a low-carb
diet. First, it works
while other stuff fails. After forty years of looking under every rock
for
risks, nobody can find anything wrong. Second, it makes sense. Directly
or
via
insulin,
carbohydrates control metabolic control matrix. Carbohydrate will
determine
what happens to the fat that you eat, whether you store it as body fat,
or burn
it for fuel.

Where we're going

Start with  the quiz that we
give to incoming medical
students before they've been exposed to any biochemistry, a test of
what
they've learned as "citizens." The quiz format provides motivation to
learn the
material – one student explained that medical students are not happy
when they
don't know the answer. Chapter 3 looks at the Low-Carbohydrate
Revolution of 2002
– how it started, how it was stopped. Chapter 4 provides an overview of
metabolism, the principles and how energy is obtained. But first,
whaddaya'
know?

Chapter
2

Whaddaya'
Know?

Take the Quiz

We give this questionnaire to first
year medical students at
the beginning of the course in metabolism before we've taught them
anything.
Although they are among the most accomplished students in the country,
like
everybody else, they've been subject to the nutritional information
available
from rumor and the front of packages in the supermarket. We don't have
accurate
feedback on the quiz but some of them like the question format and you
may too.
No particular knowledge is assumed beyond your life as nutritional
end-user.
The quiz only tests how you were able to sift through all the
information
that's out there, on the internet and in popular books. And it is a
teaching
device. The answers provide basic information. I list the questions
first so
you can see how you do. If you don't like quizzes you can skip over to
the
answers
.
We also
published an early version in the
Nutrition
Journal
[3].

1. The most
energy dense food
(most calories/gram) is:

_____ Carbohydrate.

_____ Fat.

_____ Protein.

_____ Alcohol.

2. For a
slice of buttered bread,
which is more fattening?

_____ The butter.

_____ The bread.

_____ Both are equally fattening.

_____ Cannot tell from the
information
given.

3. During the
epidemic of
obesity and diabetes, the macronutrient that increased most was:

_____ Carbohydrate.

_____ Protein.

_____ Fat.

_____ All about the same. Calories
increased across the board.

4. The
macronutrient most likely to raise blood glucose in people with type 2
diabetes
is:

_____ Carbohydrate.

_____ Protein.

_____ Fat.

_____ Alcohol.

5. The
dietary requirement for carbohydrate is:

_____ approximately 130 g/day

_____ approximately 50 % of calories

_____ as much as possible

_____ there is no dietary requirement
for
carbohydrate

6.
The
amount of carbohydrate recommended by the American Diabetes Association
and
other health agencies:

_____ approximately 130 g/day

_____ approximately 50 % of calories

_____ as much as possible

_____ as little as possible.

7.
Glycemic
Index (GI) measures the increase in blood sugar over 2 hours (per gram
of
carbohydrate-containing food that is ingested) compared to glucose
(=100). For
each food indicate the approximate glycemic index as: H, High (70–100),
M,
Medium (40–70) or L, Low (< 40). You may enter a number if you
think you
know or can figure it out:

_____ white
bread                              

_____ whole wheat
bread                 

_____ ice
cream                                  

_____
carrots                                      

_____ sucrose
(Table sugar)

_____ fructose

_____ bran
muffin

_____ banana

8.
     
A
good source of monounsaturated fat is: (check all that apply)

_____
Butter                                  

_____ Canola
Oil                         

_____ Corn
Oil                                    

_____ Flaxseed Oil

_____ Olive Oil

_____ Avocado

_____ Soybean
Oil

9.
     
The
diet component that is most likely to raise triglycerides (fat in the
blood)
is:

_____ Fat

_____ Carbohydrate

_____ Protein

10.
 
In general, what effect does
a low-fat diet have on HDL-C (high density lipoprotein cholesterol,
"good
cholesterol")

_____ Increase

_____ Decrease

_____ No change

11.
 
The dietary change that is
most likely to increase the risk of cardiovascular disease:

_____
unsaturated
fat
→
saturated fat (that is,
replace unsaturated fat with saturated fat)

_____ unsaturated fat
→
carbohydrate

_____ carbohydrate
→
unsaturated fat

_____ carbohydrate
→
saturated fat

_____ saturated fat
→
carbohydrate

_____ saturated fat
→
unsaturated fat

Answers

The calorie. The
calorimeter.

1.
 
The most energy dense food
(most calories/gram) is:

_____ Carbohydrate.

_ X __ Fat.

_____ Protein.

_____ Alcohol.

Student
Performance on Question
1
.

Our first year medical students do
surprisingly poorly
considering that question is so basic. Typically only 80 % of our
incoming
class gets this right. Although they have not yet been through the
metabolism
course, this is a very highly educated group of people and we had
assumed that
everybody knew that fat was the most energy dense macronutrient. The
explanation, which contains some information, is that they were not
curious
about nutrition because they didn't see it as part of medicine and
because they
are mostly young, healthy and thin.  

Figure
2-1
. Modern Calorimeter

The operational numbers in
kilocalories/gram are 4, 4, 9
and 7 for carbohydrate, protein, fat and alcohol. Calories are a
measure of
energy. The definition of energy in physics is not too different from
the
common idea, it is a measure of the ability to do work. Heat is one
form of
energy and the calorie is defined in terms of the amount of heat
required to
raise the temperature of water one degree. Note that the dietary
"calorie" is
equal to a physical kilocalorie (kcal), that is, 1000 physical
calories. Use of
"kcal" in nutrition is increasing and in this book we use kcal when
actually
referring to the quantity. It is one small step to help nutrition
become
scientific. The calories in food are measured in a device known as a
calorimeter. Food is placed in a small container in an atmosphere of
oxygen
under pressure and then ignited. By measuring the amount of heat
generated from
the change in temperature in the water bath, we can determine the
energy for
oxidation which can be assigned to the food. This is the real
definition of the
nutritional calorie. It all looks obvious but there are a couple of
very
important points:

The calories assigned to a food
represents
the energy for
complete combustion of that food in oxygen. Calories refers to a
chemical
reaction (not to the food):

Food + oxygen
→
carbon dioxide + water

Food + O
₂
→
CO
₂
+ H
₂
O

(said: "food plus oxygen goes to
CO-two and water").

Heat produced in the calorimeter
measures
the energy for the
specific
reaction
.
Again, the energy is in the reaction,
not
in the food
. It is not like particle physics
where the mass of a
particle is given in electron-Volts, a unit of energy (because of E = mc
²
).
We will come back to this point when we consider what is wrong with the
idea
that a "calorie is a calorie," that the amount of weight you gain or
lose on a
diet depends only on how many calories without regard to the specific
food. It
will turn out that the composition of the food is important because,
again, the
calories associated with a food is the energy obtained in the course of
complete
combustion of that food as measured in the calorimeter. If you do
anything
else, make protein, make DNA, make any kind of new cell material, then
the
calorimeter value does not apply.

Fat is the most energy dense
macronutrient
at 9 kcal/g and, for that
reason, it is considered inherently fattening by nutritionists. This is
the
basis of traditional recommendations for low-fat diets for obesity. But
there
is more to the problem than caloric density. And, it turns out that
there is
more to getting fat than total calories. To see how this all plays out
in a
real situation, consider the next question.

2. For a slice of buttered bread,
which is
more fattening?

_____ The butter.

_____ The bread.

_____ Both are equally fattening.

__ X_ Cannot tell from the
information
given.

Student
Performance on Question 2

This is a trick question. It doesn't
really have an answer, that
is "you cannot tell" is the answer. An argument could be made that 9
kcal/g is
inherently more fattening but you really need more information. If you
put a
lot of butter on the bread it would be more fattening but, in fact,
people
rarely put more than 100 kcal (tablespoon) on the bread (typically 100
kcal/slice). How fattening food is depends on how much you eat, so the
suggestion that you reduce fat because of its caloric density only
makes sense
if you don't replace it with anything, that is, reduce the calories.

Fat is the most calorically dense
food but
caloric density, like
any density, can be very misleading – density is a measure per amount
of
material or per unit volume, or per gram,
per
something, so it matters how much of something that you have. Calories
per gram
is not informative unless you know how many grams. Things like caloric
density
or any density for that matter are measures of
intensity
,
and technically these
measurements are called
intensive
variables.
Intensive variables are
independent of mass: one
tablespoon of butter has the same energy
density
(kilocalories per gram) as two tablespoons of butter, but obviously two
tablespoons has twice the
total calories
– total calories measures the
amount that you have.
Such measurements are called
extensive
variables
. Extensive variables depend on how
much you have, not
the character of the substance. It is the same as the old (updated)
riddle:
which is heavier? A pound of uranium or a pound of styrofoam? Of course
they
are the same. A pound is a pound. Uranium has an extremely high density
(about
1.6 times that of lead) so a pound of uranium is only a little bigger
than a
major league baseball but you would have to fill up the room with
styrofoam to
equal the same pound.

Fraction, or percent is another kind
of
measure of intensity that
can be misleading. Looking ahead, this is one reason that
recommendations on
percent of increase in risk that is always reported in the media is
usually
meaningless: your odds of winning the lottery are increased by 100 %,
that is,
doubled, by buying two tickets instead of one. Does that make you want
to play?
Bottom line: when you hear people say that fat has more calories per
grams, you
know that is irrelevant. You have to know how many grams you are
actually
eating.