Found this posted on sci.med.nutrition

Steve

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The Tail End of the Fiber Myth

October 13, 2000, FoxNews.com

If you’ve been shoveling down high-fiber cereals every morning in
hopes of preventing colon cancer, you can stop. The 30-year old notion
that cereal fiber reduces colon cancer risk is turning out to be yet
another government-sanctioned myth. It may be time for the Food and
Drug Administration to butt out of our colons.

A study published in this week’s The Lancet reports that a “... high-
fiber diet and supplementation with wheat bran fiber may not be
effective strategies for the prevention of [colon cancer].” By itself
the study would not be overly persuasive. But it is the fourth study
in a major medical journal in the last two years to reach the same
conclusion, including a January 1999 study in the New England Journal
of Medicine that followed about 89,000 women over a period of 16
years.

How did the myth get started?

British medical missionary Dr. Denis Burkitt gave birth to the idea
that dietary fiber reduced colon cancer risk in 1971. Burkitt observed
— almost casually, not in any scientific manner — that poor rural
Africans had much less colon cancer than Westerners. He theorized this
was due to the Africans’ fiber-rich diet.

The idea was that larger, fastermoving stools reduced the colon’s
exposure to carcinogenic bile acids. The theory’s intuitive appeal
propelled it to become conventional wisdom. But it lacked persuasive
scientific support. Some studies seemed to support the theory; others
did not. None of the studies were particularly well-designed — they
tended to be retrospective in nature, relying on unverified self-
reports of subjects’ dietary and lifestyle habits .

The National Research Council, the research arm of the National
Academy of Sciences, thought the theory was so speculative that it
declined in 1982 to make a specific recommendation about dietary fiber
and colon cancer.

Eventually, though, commercial interests perceived value in the theory
and the scientific controversy became a memory.

In 1984, cereal manufacturer Kellogg placed a message on its All Bran
cereal claiming scientific evidence linking a high fiber diet with a
reduction in colon cancer risk. The FDA took no action against
Kellogg, though the action seemed to defy a longstanding FDA rule
prohibiting healthrelated message on food products.

The National Research Council reversed itself and came out in favor of
a link between dietary fiber a reduced colon cancer risk in 1989 —
though the state of the science had not changed. A 1990 federal law
clarified the FDA’s authority over food label content and the agency
subsequently issued rules permitting health-claims labeling provided
there was some scientific support.

In a 1997 effort to boost stagnant cereal product sales, Kellogg
petitioned the FDA for permission to make the claim that some of its
products contain ingredients that may help prevent certain cancers,
especially colon cancer. In July 1999, the FDA permitted whole-grain
foods to claim on their labels that “diets rich in wholegrain foods
and other plant foods and low in total fat, saturated fat and
cholesterol may reduce the risk of heart disease and certain
cancers.”

The FDA did not give the scientific research on wholegrain foods the
scrutiny that goes into the approval of a new drug. Instead, the
agency relied on recommendations made by the NRC 10 years earlier. The
FDA ignored the New England Journal of Medicine study that was
published six months before the approval of the Kellogg petition —
even though it was largest study ever on dietary fiber and colon
cancer.

The result of the FDA’s scientific sloth is that millions of consumers
will continue to be misled for the foreseeable future about an
important health issue — all the while choking down bran cereals and
imagining they’re preventing colon cancer. Certainly whole grains are
part of a balanced diet. But by overestimating the benefits, many will
have a false sense of security.

And while the FDA is allowing companies to market junk science-fueled
myths, the agency uses junk science to remove a product with known
benefits. Maybe you’ve noticed that your favorite laxative doesn’t
work as well as it used to.

Researchers from the U.S. Government’s National Toxicology Program
reported to the FDA in April 1997 that mice fed high doses of the
compound phenolphthalein had higher rates of cancer. At the time,
phenolphthalein was the most effective active ingredient in laxative
products.

The FDA bullied laxative manufacturers to reformulate their products
without phenolphthalein despite that: (1) the mice were genetically
engineered to be more susceptible to cancer — they were, in a sense,
“cancer time bombs”; (2) the doses of phenolphthalein were 30 times
higher than consumer use; and (3) phenolphthalein was used as a
laxative ingredient for more than 100 years with absolutely no
indication of increased cancer risk among users.

The several scientific studies published after the FDA decision also
failed to link laxative-use with increased cancer risk.

Hey, who needs laxatives when you’ve got bran?

President Clinton this week announced a new effort to fight colon
cancer, including among other recommendations that adults over the age
of 50 years have annual colon cancer screenings. There are an
estimated 130,000 new cases of, and more than 50,000 deaths from colon
cancer every year.

Colon cancer may be cured if detected early enough. It’s too bad there
doesn’t seem to be any cure for junk science at the FDA.

SOURCE: http://www.junkscience.com/foxnews/fn101300.htm