Extract from Archives of Internal Medicine 2009 [169(6):562-571]

"We examined total and cause-specific mortality in relation to meat consumption
in a large prospective study. We found modest increases in risk for total
mortality, as well as cancer and CVD (cardiovascular disease) mortality, with
higher intakes of red and processed meat in both men and women. In contrast,
higher white meat consumption was associated with a small decrease in total and
cancer mortality in men and women.

"The principal strength of this study is the large size of the cohort, which
provided us the ability to investigate the relationship of many deaths (47 976
male deaths and 23 276 female deaths) within the context of a single study with
a standardized protocol and a wide range of meat consumption.

"We found a positive association for processed meat intake and cancer mortality
among former/current smokers but not among never smokers..in addition to being
exposed to N-nitroso compounds from processed meats, smokers inhale carcinogenic
chemicals.

"Overall, we did not find statistically significant association between meat
consumption and deaths from injury and sudden deaths in most instances. The
relative HRs of meat consumption with the other causes of death (total, cancer,
and CVD mortality) were similar in magnitude in some cases to those of deaths
from injury and sudden deaths; however, the number of deaths from injury and
sudden deaths was less than the other causes of deaths, and thus the HRs were
generally not statistically significant. We observed a higher risk with the
category that included "all other deaths"; this is a broad category with many
heterogeneous conditions (eg, diabetes mellitus, Alzheimer disease, stomach and
duodenal ulcers, chronic liver disease, cirrhosis, nephritis, nephrotic
syndrome, and nephrosis), some of which may be positively related to meat
intake.

"There are various mechanisms by which meat may be related to mortality. In
relation to cancer, meat is a source of several multisite carcinogens, including
heterocyclic amines and polycyclic aromatic hydrocarbons, which are both formed
during high-temperature cooking of meat, as well as N-nitroso compounds. Iron in
red meat may increase oxidative damage and increase the formation of N-nitroso
compounds. Furthermore, meat is a major source of saturated fat, which has been
positively associated with breast and colorectal cancer.

"In relation to CVD, elevated blood pressure has been shown to be positively
associated with higher intakes of red and processed meat, even though the
mechanism is unclear, except that possibly meat may substitute for other
beneficial foods such as grains, fruits, or vegetables. Mean plasma total
cholesterol, low-density lipoprotein cholesterol, very-low-density lipoprotein
cholesterol, and triglyceride levels were found to be decreased in subjects who
substituted red meat with fish. Vegetarians have lower arachidonic,
eicosapentaenoic, and docosahexaenoic acid levels and higher linoleate and
antioxidant levels in platelet phospholipids; such a biochemical profile may be
related to decreased atherogenesis and thrombogenesis.

"Red and processed meat intakes, as well as a high-risk meat diet, were
associated with a modest increase in risk of total mortality, cancer, and CVD
mortality in both men and women. In contrast, high white meat intake and a
low-risk meat diet was associated with a small decrease in total and cancer
mortality. These results complement the recommendations by the American
Institute for Cancer Research and the World Cancer Research Fund to reduce red
and processed meat intake to decrease cancer incidence.

[The full report is here:
http://archinte.ama-assn.org/cgi/content/full/169/6/562]