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Authors: T. Colin Campbell,Thomas M. Campbell

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THE CHINA STUDY
98
been shown many times to cause significant weight loss. But it's not
quite as simple as that.
At least 99% of the carbohydrates that we consume are derived from
fruits, vegetables and grains. When these foods are consumed in the
unprocessed, unrefined and natural state, a large proportion of the car-
b o h y d r a t e s are in the so-called "complex" form. This means that they
are broken down in a controlled, regulated manner during digestion.
This category of carbohydrates includes the many forms of dietary fiber,
almost all of which remain undigested-but still provide substantial
health benefits. In addition, these complex carbohydrates from whole
foods are packaged with generous amounts of vitamins, minerals and
accessible energy. Fruits, vegetables and whole grains are the healthiest
foods you can consume, and they are primarily made of carbohydrates.
On the opposite side of the spectrum, there are highly processed, high-
ly refined carbohydrates that have been stripped of their fiber, vitamins
and minerals. Typical simple carbohydrates are found in foods like white
bread, processed snack items including crackers and chips made with
white flour, sweets including pastries and candy bars and sugar-laden soft
drinks. These highly refined carbohydrates originate from grains or sugar
plants, like sugar cane or the sugar beet. They are readily broken down
during digestion to the simplest form of the carbohydrates, which are
absorbed into the body to give blood sugar, or glucose.
Unfortunately, most Americans consume voluminous amounts of
simple, refined carbohydrates and paltry amounts of complex carbo-
hydrates. For example, in 1996, 42% of Americans ate cakes, cookies,
pastries or pies on any given day, while only 10% ate any dark green
vegetables. 46 In another ominous sign, only three vegetables accounted
for half of the total vegetable servings in 199646 : potatoes, which were
mostly consumed as fries and chips; head lettuce, one of the least nutri-
e n t - d e n s e vegetables you can consume, and canned tomatoes, which is
probably only a reflection of pizza and pasta consumption. Add to that
the fact that the average American consumed thirty-two teaspoons of
added sugars per day in 1996,46 and it's clear that Americans are gorging
almost excluSively on refined, simple carbohydrates, at the exclusion of
healthful complex carbohydrates.
This is bad news, and this, in large measure, is why carbohydrates as
a whole have gotten such a bad rap; the vast majority of carbohydrates
consumed in America are found in junk food or grains so refined that
they have to be supplemented with vitamins and minerals. On this
LESSONS FROM CHINA                            99
point, the popular diet authors and I agree. For example, you could eat
a low-fat, high-carbohydrate diet by exclusively eating the following
foods : pasta made from refined flour, baked potato chips, soda, sugary
cereals and low-fat candy bars. Eating this way is a bad idea. You will
not derive the health benefits of a plant-based diet eating these foods. In
experimental research, the health benefits of a high-carbohydrate diet
come from eating the complex carbohydrates found in whole grains,
fruits and vegetables. Eat an apple, a zucchini or a plate of brown rice
topped with beans and other vegetables.
THE CHINA STUDY WEIGHS IN
With regard to weight loss, there are some surprising findings from the
China Study that shed light on the weight loss debate. When we started
the China Study, I thought that China had the opposite problem from
that of the U.S. I had heard that China could not feed itself, that it was
prone to famines and that there was not enough food for people to at-
tain their full adult height. Very simply, there were not enough calories
to go around. Although China has, during the last fifty years, had its
share of nutritional problems, we were to learn that these views on calo-
rie intake were dead wrong.
We wanted to compare the calorie consumption in China and
America, but there was a catch. Chinese are more physically active than
Americans, especially in rural areas, where manual labor is the norm. To
compare an extremely active laborer with an average American would
be misleading. It would be like comparing the amount of energy con-
s u m e d by a manual laborer at hard work with the amount of energy
consumed by an accountant. The vast difference in calorie intake sure
to exist between these individuals would tell us nothing of value and
only confirm that the manual laborer is more active.
To overcome this problem, we ranked the Chinese into five groups
according to their levels of physical activity. After figuring out the calo-
rie intakes of the least active Chinese, the equivalent of office workers,
we then compared their calorie intake with the average American. What
we found was astonishing.
Average calorie intake, per kilogram of body weight, was 30% higher
among the least active Chinese than among average Americans. Yet,
body weight was 20% lower (Chart 4.11). How can it be that even the
least active Chinese consume more calories yet have no overweight
problems? What is their secret?
THE CHINA STUDY
100
CHART 4.11: CALORIE CONSUMPTION (KCAL/KG)
AND BODY WEIGHT
Average Body Mass Index
Calorie Intake (kcal/kg)
30
25
20
15
10~~--~~~---L~
u.s.
China
u.s.
China
There are two possible explanations for this apparent paradox. First,
even the Chinese office workers are more physically active than aver- .
age Americans. Anyone familiar with China knows that many office
workers travel on bicycles. Thus, they consume more calories. Even so,
we cannot tell how much of the extra calorie consumption was due to
physical activity and how much to something else, perhaps their food.
We do know, however, that some people use the calories they con-
s u m e differently from other people. We often say that "they have a
higher rate of metabolism" or "it's in their genes." You know these
people. They are the ones who seem to eat all they want and still not
gain weight. Then there are most of us, who need to watch our calorie
intake-or so we think. This is the simplistic interpretation.
I have a more comprehensive interpretation that is based on our own
considerable research and on the studies of others. It goes like this.
Provided that we aren't restricting our calorie intake, those of us who
consume a high-fat, high-protein diet simply retain more calories than
we need. We store these calories as body fat, perhaps weave it into our
muscle fibers (we call it "marbling" in beef animals) and perhaps store
it in the more obvious places, like our butt, our midsection or around
our face and upper thighs.
Here's the clincher: only a small amount of calories needs to be re-
tained by our body to cause significant change in body weight. For ex-
ample, if we retain only an extra fifty calories per day, this can lead to an
extra ten pounds per year. You may not think that this is a lot, but over
a period of five years, that's an extra fifty pounds.
Some people would hear this and might be inclined to just eat fifty
fewer calories per day. This, theoretically, could make a difference, but it
LESSONS FROM CHINA                              101
is entirely impractical. It is impossible to keep track of daily calorie in-
take with such precision. Think about eating a meal at a restaurant. Do
you know how many calories each meal has? What about the casserole
you might fix? What about the steak you might buy? Do you know the
number of calories they contain? Of course not.
The truth is this: despite any short-term caloric restriction regimes
we may follow, our body, through many mechanisms, will ultimately
choose how many calories to take in and what to do with them. Our at-
t e m p t s to limit calorie intake is short-lived and imprecise, whether we
do it by limiting carbohydrates or fat.
The body employs a delicate balancing act and some very intricate
mechanisms in deciding how to use the calories being consumed.
When we treat our body well by eating the right foods, it knows how
to partition the calories away from body fat and into the more desirable
functions like keeping the body warm, running the body metabolism,
supporting and encouraging physical activity or just disposing of any
excess. The body is using multiple intricate mechanisms to decide how
calories get used, stored or "burned off."
Consuming diets high in protein and fat transfers calories away from
their conversion into body heat to their storage form-as body fat
(unless severe calorie restriction is causing weight loss). In contrast,
diets low in protein and fat cause calories to be "lost" as body heat. In
research, we say that storing more calories as fat and losing less as heat
means being more efficient. I bet that you would rather be a little more
inefficient and convert it into body heat rather than body fat, right?
Well, simply consuming a diet lower in fat and protein can do this.
This is what our China Study data show. Chinese consume more
calories both because they are more physically active and because their
consumption of low-fat, low-protein diets shifts conversion of these
calories away from body fat to body heat. This is true even for the least
phYSically active Chinese. Remember, it takes very little, only fifty calo-
ries a day, to change our storage of body fat and thus change our body
weight. 58
We saw the same phenomenon in our experimental animals fed the
low-protein diets. They routinely consumed slightly more calories,
gained less weight, disposed of the extra calories as body heat59 and vol-
u n t a r i l y exercised more,60 while still having far less cancer than animals
on standard diets. We found that calories were "burned" at a faster rate
and transformed into body heat as more oxygen was consumed. 59
THE CHINA STUDY
102
Understanding that diet can cause small shifts in calorie metabo-
lism that lead to big shifts in body weight is an important and useful
concept. It means that there is an orderly process of controlling body
weight over time that does work, as opposed to the disorderly process
of crash diets that don't work. It also accounts for the frequent observa-
t i o n s (discussed in chapter six) that people who consume low-protein,
low-fat diets composed of whole plant foods have far less difficulty with
weight problems, even if they consume the same, or even slightly more,
total calories.
DIET AND BODY SIZE
We now know that eating a low-fat, low-protein diet high in complex
carbohydrates from fruits and vegetables will help you lose weight. But
what if you want to become bigger? A desire to be as big as possible
is pervasive in most cultures. During the colonial period in Asia and
Africa, Europeans even considered smaller people to be less civilized.
Body size seems to be a mark of prowess, manliness and dominance.
Most people think they can be bigger and stronger by eating protein-
rich animal-based foods. This belief stems from the idea that consuming
protein (a.k.a. meat) is needed for physical power. This has been a com-
m o n notion the world over for a long time. The Chinese have even of-
ficially recommended a higher-protein diet in order to encourage bigger
athletes and to better compete in the OlympicS. Animal-based foods have
more protein, and this protein is considered to be of "higher quality." Ani-
mal protein enjoys the same reputation in a rapidly modernizing China
as everywhere else.
There is, however, a problem with the idea that consuming animal-
based foods is a good way of becoming bigger. The people who eat the
most animal protein have the most heart disease, cancer and diabetes. In
the China Study; for example, animal protein consumption was associated
with taller and heavier! people, but was also associated with higher levels
of total and bad cholesterolY Furthermore, body weight, associated with
animal protein intake,! was associated with more cancerII -III and more cor-
o n a r y heart diseaseY It seems that being bigger, and presumably better,
comes with very high costs. But might it be possible for us to achieve our
full growth potential, while Simultaneously minimizing disease risks?
Childhood growth rates were not measured in the China Study but
adult height and weight were. This information proved surprising.
Consuming more protein was associated with greater body size (III for
103
LESSONS FROM CHINA
men and 11 for women).6l However, this effect was primarily attributed
to plant protein, because it makes up 90% of the total Chinese protein
intake. Animal protein consumption was indeed associated with greater
body weight,l and consumption of protein-rich milk seemed to be effec-
tive as well.1! But the good news is this: Greater plant protein intake was
closely linked to greater heightI l and body weightY Body growth is linked
to protein in general and both animal and plant proteins are effective!
This means that individuals can achieve their genetic potential for
growth and body size by consuming a plant-based diet. So why is it that
people in developing nations, who consume little or no animal-based
foods, are consistently smaller than Western people? This is because
plant-based diets in poor areas of the world usually have insufficient
variety, inadequate quantity and quality and are associated with poor
public health conditions where childhood diseases are prevalent. Under
these conditions, growth is stunted and people do not reach their ge-
netic potential for adult body size. In the China Study, low adult height
and weight were strongly associated with areas having high mortality
rates for pulmonary tuberculosis,IIl parasitic diseases,JIl pneumonia (Ill
for height) , "intestinal obstruction"m and digestive diseases. III
These findings support the idea that body stature can be achieved
by consuming a low-fat, plant-based diet, provided that public health
conditions effectively control the diseases of poverty. Under these con-
ditions, the diseases of affluence (heart disease, cancers, diabetes, etc.)
can be simultaneously minimized.
The same low-animal protein, low-fat diet that helps prevent obesity
also allows people to reach their full growth potential while working
other wonders as well. It better regulates blood cholesterol and reduces
heart disease and a variety of cancers.
What are the odds that all of these associations (and many others)
favoring a plant-based diet are due to pure chance? It is extremely un-
likely, to say the least. Such consistency of evidence across a broad range
of associations is rare in scientific research. It points to a new worldview,
a new paradigm. It defies the status quo, promises new health benefits
and demands our attention.

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