LESSONS FROM CHINA 91when we compared these measurements with fiber intake, there was no
evidence showing that increasing fiber intake impaired iron absorption in
the body. In fact, we found the opposite effect. A good indicator of how
much iron is in the blood, hemoglobin, actually increased with greater
intakes of dietary fiber. I As it turns out, high-fiber foods, like wheat
and corn (but not the polished rice consumed in China) also happen to
be high in iron, meaning that the higher the consumption of fiber, the
higher the consumption of ironYI Iron intake in rural China (34 mg/
day) was surprisingly high when compared to the average American in-
take (18 mg/day) and it was far more associated with plant-based foods
than with animal-based foodsY
The China findings on dietary fiber and iron, like so many other ob-
servations in this study, did not support the common view of Western
scientists. People who consume more plant-based foods, thus more di-
etary fiber, also consume more iron,III all of which results in statistically
significant higher levels of hemoglobin. Unfortunately, a bit of confu-
sion has arisen over the fact that some people in rural China, including
women and children, have low iron levels. This is especially true in
areas where parasitic diseases are more common. In areas of rural China
where parasitic diseases were more common, iron status was lower. I
This has given some the opportunity to claim that these people need
more meat, but the evidence indicates that the problem would be much
better corrected by redUcing parasitism in these areas.
Much of the initial interest in dietary fiber arose with Burkitt's travels
in Africa and his claim that large bowel cancer is lower among popula-
tions who consume high-fiber diets. Burkitt made this claim popular
but the story is at least 200 years old. In England during the late eigh-
teenth century and early nineteenth century, it was claimed by some of
the leading phYSicians that constipation, which was associated with less
bulky diets (i.e., low-fiber diets), was associated with a higher risk of
cancer (usually breast and "intestinal" cancers).
At the beginning of the China Study, this belief that fiber might pre-
vent large bowel cancer was the prevailing view, although the 1982 Na-
tional Academy of Sciences Committee on Diet, Nutrition and Cancer,
"found no conclusive evidence to indicate that dietary fiber ... exerts a
protective effect against colorectal cancer in humans." The report went
on to conclude, " ... if there is such an effect, specific components of
fiber, rather than total dietary fiber, are more likely to be responsible."20
In hindSight, our discussion of this issue was inadequate. The question,