The China Project differs from other scientific studies in several
important ways:
- It utilizes the most comprehensive database on the multiple causes
of disease ever compiled; the Chinese government provided background
data on eighty million Chinese people.
- It examines relationships between health and diet in a holistic way,
by considering ways in which complete diets and other lifestyle patterns
affect health. By contrast, most contemporary studies focus on
relationships between single nutrients or foods and single diseases.
- China provided a "natural (living) laboratory" for the study of
nutrition and disease that is unmatched anywhere else in the world; while
people in most of the world's countries frequently change their places of
residence, and eat foods from many different regions of the world, most
Chinese live their entire lives in one area, and eat the same kinds of locally
grown food throughout their lives. Yet, diets (and disease rates) vary
sharply from one area to another.
The China Project has received much critical acclaim. Jane Brody,
nutrition editor of the New York Times, has called it "the grand prix" of
epidemiology, and has hailed its "tantalizing findings" from "the most
comprehensive large study ever undertaken of the relationship between
diet and the risk of developing disease." The East West Journal has called
the study "one of the most rigorous and conclusive [studies] in the history
of health research," one that has "unprecedented authority."
Here are some of the "tantalizing findings" that can (and should) have
a global impact:
- The Chinese diet, composed primarily of rice and other grains,
vegetables, and legumes, such as soy products, is far healthier than the
standard American diet. While Americans get an average of thirty-seven
percent of their calories from fat, Chinese get an average of 14.5 percent,
with a range of about six percent to twenty-four percent. The Chinese get
only ten percent of their protein from animal sources, while Americans get
seventy percent. One result of the healthier Chinese diets is that the range
of cholesterol levels in China vary from seventy mg to 170 mg, while in the
United States, the average cholesterol level is over 200.
- In China, regions in which people eat the most animal products
have the highest rates of heart disease, cancer, and other degenerative
diseases. In many cases, the differences are extremely large; for example, in
one part of China where people eat more meat, the rate of esophageal
cancer for men is 435 times greater than the rate for men in another
region, and twenty times as many women in one county with high meat
consumption suffer from breast cancer as women in another county where
meat consumption is much lower.
- Degenerative diseases are associated with high levels of blood
cholesterol and urea nitrogen (what is left over after the metabolism of
protein in the body), and both of these factors increase as people eat more
meat, dairy products, and eggs.
- The more a diet is composed of foods of plant origin, the better.
Even small increases in the amount of animal products (meat, eggs, and
dairy products) consumed result in significant increases in chronic
degenerative diseases.
- Because cholesterol levels in the United States are almost double
those in China, heart disease deaths among American men occur
seventeen times more often, per thousand men, than for Chinese men.
Also, Chinese at the lower end of the cholesterol range have significantly
less cancer and heart disease than those at the upper end.
- Deaths from breast cancer are linked to five factors associated with
diets high in animal-based foods: high intakes of dietary fat, high levels of
blood cholesterol, high amounts of estrogen, high levels of blood
testosterone, and early age at first menstruation. The Chinese's plant-based
diets give them benefits in each of these areas. For example, Chinese
girls reach menstruation when they are fifteen to nineteen years of age,
significantly later than the ten to fourteen years of age for most American
girls.
- Chinese eat very few dairy products, and low levels of calcium-rich
foods; yet they get far less osteoporosis than Westerners. For example, hip
fractures per thousand people in China are only one-fifth of what they are
in the West. (The reason
is that excessive animal protein causes calcium to be excreted from the
body.)
- While the Chinese eat an average of almost 300 calories per day
more than Westerners do, they are generally thinner. Dr. Campbell
believes that in a very low-fat diet, a higher percentage of calories may be
burned up rather than stored as fat.
- The amount of animal protein in the diet correlates well with
overall cancer rates, Hence, dietary protein may be a bigger health
problem than dietary fat. Thus a shift from red meat to fish and chicken is
generally not helpful since, while dietary fat is reduced, dietary animal
protein is not.
