The World Turned Upside Down: The Second Low-Carbohydrate Revolution (23 page)

I
also
decided that I really, really like dark chocolate and given that it is
full of
antioxidants, I do allow myself some. I save my carbs for it. The 85%
variety I
eat has 4g/square and is much more satisfying than milk chocolate, so
it's
possible to enjoy without over-indulging. There are days too when I
decide that
it's a "Carb Day". For example, one very hot day in the summer warrants
my
once-a-year small ice cream or custard cone. Or if some kind person
makes me a
birthday cake I'll eat a bit. I call these excursions "experimental
error." I
am not perfect, but I try to keep my carbohydrate intake under 50g/day
and
ideally around 30g/day. For me, the lower my carbohydrate, the far
better my
control.

Chapter
12

Metabolic
syndrome -
the big pitch

The last two chapters brought out the
idea that diabetes
represents the most clear-cut example of how the glucose-insulin axis
affects
health. This disease is at the center of nutritional thinking even if
you are
not a patient yourself. Even if you are primarily interested in weight
loss or
have concern about cardiovascular disease (CVD) or you are just
interested in
general good health, insulin metabolism is always in the foreground. A
big
focal point is the metabolic syndrome (MetS). Gerald Reaven's original
observation
[12,
70]
was that
overweight, high blood glucose, high blood pressure and the lipid
markers
assumed to indicate cardiovascular risk commonly appeared together in
the same
patient (
Figure 12-1
).

Figure
12-1
. Definitions of metabolic syndrome.
Different organizations
have their own variations and other factors such as LDL-particle size
have been
included by some researchers.

The concept has now been extended to
include several other
physiologic markers, inflammation and LDL particle size, that also seem
to be
tied together. Insulin is credited with control of the syndrome and
Reaven
currently insists on calling it insulin-resistance syndrome
[71,
72]
.

I may have said
something smart.

The importance of metabolic syndrome
came through to me a
few years ago. It was a seminar was on metabolic syndrome and the
underlying
cell biology. I don't remember the details of the presentation but I
thought it
was quite good. The speaker was also a doctor. In fact, he was Mike
Huckabee's
doctor. After the seminar, I asked him about low-carbohydrate diets and
he
unexpectedly went ballistic. "Go to the Atkins website. You can eat all
the
bacon you want. That's what it says." I was somewhat taken aback. Did I
say
Atkins? I didn't really know what to say. I noticed that he still had
on the
screen his last slide showing the metabolic syndrome (something like
Figure 12-1
).

Pointing to the screen, I said "you
know, all of those
markers are exactly the things that are improved by low carb
diets.  He
said, "Well, they're also improved by low calorie diets," which is not
true. Low-Fat diets, or at least high carbohydrate diets, will
not improve
triglycerides and, more likely, will make them worse. 

The incident stuck in my
head. A little later that day
I thought "I may have said something smart." The features of MetS were
known to
be improved by carbohydrate restriction but it was not generally stated
explicitly. Turning it around in your mind, you might say that the
response to
a low-carbohydrate diet could actually be the essential feature of
metabolic
syndrome, a kind of operational definition.  This is important
because some
people said that MetS was not for real. They held that saying that your
patient
has the combination of markers of metabolic syndrome provides no more
information than saying that they have several individual
markers. What
they mean is that the way to treat markers A, B and C (for example,
obesity,
diabetes and high cholesterol) is with a drug for A, a drug for B and a
drug C.
In other words, they didn't have a drug for MetS. They only a have
drugs for
each of the individual markers. The fact that A, B and C can
all be
treated with a single intervention, namely a low-carbohydrate diet,
suggests
that they all arise from a common cause: a disruption in the
glucose-insulin
axis, roughly described as insulin resistance.  Other people
had said this
in other publications. I had even written a paper myself entitled
"Metabolic
Syndrome and Low-Carbohydrate Ketogenic Diets in the Medical School
Biochemistry Curriculum." but I hadn't really seen the
impact.  There is a
step in the evolution of ideas where you realize that the comment you
made in
passing has important implications and has to be re-stated as a law.
 

If all the markers of metabolic
syndrome could be improved
by a low-carbohydrate diet, possibly even in the absence of calorie
restriction, than what did that mean for the millions of people facing
the risk
predicted by these markers? What did it mean for the drugs
that treat
each individual condition but ignore the root cause? And what did it
mean for
those national authorities on health that were and are still
recommending a
low-fat, high carbohydrate diet? If the experimental data is
there, would
the nutritional establishment embrace it even though it contains the
words
"low-carbohydrate." It was 2005 and we really thought that they would.
Talk about
the naïveté of youth.

Jeff Volek and I went through the
literature and tabulated
the responses to low-carbohydrate and low-fat diets with respect to the
markers
of MetS. The results were as expected (
Figure
12-2
).
We published the results in
Nutrition
& Metabolism
[38]
.
I was the editor at
the time and thought that the importance of the paper would improve the
standing of our journal. We recognized that we were dealing with modern
science
where people don't even have time to read an abstract so we put the
whole story
in the title: "Carbohydrate restriction improves the features of
Metabolic
Syndrome. Metabolic Syndrome may be defined by the response to
carbohydrate
restriction." The data show that except for a couple of measurements
(one on
insulin, one of fasting glucose), the markers of MetS are improved much
more by
a low-carbohydrate diet, sometimes dramatically.

Figure
12-2
. Comparison of effects on markers of
metabolic syndrome of
low-carbohydrate and low-fat diets. Data from reference
[38]
.

Probably the best indicator of CVD
risk of commonly-measured
parameters is the ratio of triglycerides:HDL where the reduction is
typically
3-10 times greater in carbohydrate reduction.

Volek's test of the
theory.

Chapter 9 described the experiments
in Jeff Volek's
laboratory showing that saturated fat in the blood was
reduced
by a
low-carbohydrate diet with high saturated fat compared to low-fat diet
with low
saturated-fat. The results on control of plasma saturated fat are
critical
since the presence of dietary saturated fat is still an objection to
low-carbohydrate diets. It was also the magnitude of the effect that
was
surprising. The total SFA fraction in the low-carb arm was reduced by
more than
half, and this reduction was more than three times the average change
in the
low-fat arm. This study had a larger overall significance, however.

Figure
12-3.
Summary of responses of 40 people with
metabolic syndrome
to very-low-carbohydrate ketogenic diet (VLCKD) or low-fat diet (LFD).
Data
from Volek,
et al
.
[30,
31,
61]
.

The real power of Volek's
experiments, however, is that the
participants all fit the definition of metabolic syndrome and a wide
variety of
lipid, and physiologic parameters were measured.
Figure
12-3
shows you that everything got better: HDL, insulin,
leptin and,
most dramatically, triglycerides.

The pitch.

This chapter reinforces the big
pitch: If metabolic syndrome
(MetS) is a real thing. If seemingly different physiologic effects –
overweight, high blood pressure, atherogenic dyslipidemia (high
triglycerides,
low HDL, high blood glucose, high insulin) – are all a reflection of a
common
underlying stimulus (proposed to be disruption in insulin metabolism),
then if
we can treat any one of those features, we can treat them all.

Nothing is better than low-carb for
weight loss but lots of
diets work. It's harder for women and it's harder as you get older but
there
are lots of ways to get thinner. We don't really have the answer on
CVD. We
know a lot of things that may be relevant but we don't really know the
fundamental cause. We
do
know about diabetes. Cutting back on carbohydrate is the most effective
treatment. For many it is a virtual cure. In the long term, it is
better than
drugs. So, if MetS is real, then effectively treating hyperglycemia
will
improve all of the features of MetS, that is,  we have a
prescription for
general health.

The
Head-and-shoulders effect.

In addition to metabolic effects, a
low-carbohydrate diet
will cure irritable bowel syndrome and related disorders in many
people. (And
cancer is waiting in the wings). In some sense, the problem with
convincing
people of the benefits of a reduced carbohydrate strategy is that it
appears to
be good for everything, good for what ails you. You can sound like a
hard-sell
pitchman. I call this the Head-and-Shoulders® effect. I don't know
whether it
is true but a rep from Proctor and Gamble once told me that when they
first brought
out the shampoo of that name, they advertised that it would cure your
dandruff
in three days. What their tests actually showed was that it would cure
it in
one day but they didn't think anybody would believe that.

Summary.

Metabolic syndrome is a profound
biological concept. We
may underestimate its importance because we've become used to the idea,
but the
fact that a group of clinical markers – overweight, high blood glucose,
high
insulin, high blood pressure and a group of lipid markers, high
triglycerides,
low HDL – should all have a high frequency of appearing together is
unusual.
They are not superficially similar. That they can all be brought under
control
by a single intervention, dietary carbohydrate restriction, suggests
that they
really are part of a syndrome with a common cause related in some way
to the
global effects of insulin. Volek's experiment is consistent with many
studies
in the literature but, because of the number of different parameters
that were
measured and because of the dramatic effects, it stands as a kind of
classic
experiment, under-appreciated but scientifically compelling.

The global effects of
low-carbohydrate diets extend beyond
metabolism and include a treatment for gastrointestinal problems
[73]
. There is also the
well-known, if poorly
investigated, effect on appetite. If there is confusion in metabolism,
adding
psychology into the mix can only make things worse since, in some
sense, we
don't even know what hunger is. The next chapter provides my take on
things.