The Role of Beef in the American Diet - International Meat Secretariat

The Role of Beef in the American Diet
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Inconsistent Findings
In 1997, the World Cancer Research Fund published a comprehensive
review of the scientific evidence on diet and cancer, which ranked
various links between specific foods and cancer as “convincing,” “probable,”
or “possible.” The most notable conclusion of this report was that
there was “convincing” evidence that ample intakes of vegetables and
fruits reduce the risk of a variety of cancers; that conclusion remains
valid today. More tentatively, the report concluded that there was a
“probable” link between high intake of red meat and increased risk of
colon cancer, and “possible” links between red meat and breast and
prostate cancers (33).
Since 1997, additional scientific studies have been completed, with
inconsistent results. One recent expert review noted that the majority of
additional studies of colon cancer published since 1997 have not associated
meat intake with increased risk; thus, the weight of evidence pertaining
to colon cancer may be weaker than the “probable” status it had
in 1997 (34). A recent combined analysis of eight major breast cancer
studies found no association between red meat intake and the risk of
this type of cancer (35). In fact, there is little convincing evidence for
an association of any specific dietary factors with breast cancer risk,
although obesity may play a role (36). Uncertainties also remain with
regard to prostate cancer; the evidence for a link with dietary factors is
still considered tentative rather than conclusive (37).
Until more is learned about the relationship between cancer risk and
specific dietary factors such as red meat intake, moderation rather than
drastic dietary change is the best course of action. A well-balanced diet
that includes reasonable amounts of foods from all the major food
groups, without excessive intakes of saturated fat or total calories, is the
most prudent choice.
Substances Produced by Cooking
Concerns have been raised about the presence of substances called
heterocyclic amines in some cooked meat and poultry, including beef.
Laboratory experiments have shown that heterocyclic amines can cause
mutations in a cell’s genetic material and that, like many other mutagens,
heterocyclic amines can cause cancer when fed to laboratory animals
in very high doses (38).
Heterocyclic amines are formed when components of proteins react
with another substance, called creatine, when subjected to intense heating.
This reaction is almost entirely limited to muscle foods (meats)
because most other foods do not contain creatine. Heterocyclic amines