Study Bolsters Cancer-Beef Link
February 07, 2005
A new study published in the January 2005 issue of the Journal of the American Medical Association presents perhaps the most compelling evidence yet of the link between meat consumption and colorectal cancer. Nearly 150,000 men and women participated in the American Cancer Society survey, which recorded subjects’ meat intake in 1982 and again in 1992 and 1993.
The upshot: Those with a high meat intake were 30% to 40% more likely to develop colorectal cancer than their less carnivorous peers. High meat intake was considered 3 ounces/day for men and 2 ounces/day for women (about the size of a fast-food hamburger). Low intake was less than 4 ounces a week for men and 2 ounces a week for women. An even higher risk was associated with the consumption of processed meat like bacon and bologna.
Researchers speculate that a few factors may be in play. Animal fat and processed meat may harbor more toxins than other protein sources, while it’s also possible that high-meat diets might be lower in the fruit-and-vegetable fiber that keeps digestion moving more quickly through the colon. Moreover, the form of iron found in red meat may be hard on colon tissue, increasing its vulnerability to cancer-causing free radical damage.
More bad news for burgers and baby backs was borne by a University of Manchester study published in the December 2004 journal Arthritis and Rheumatism linking meat consumption with increased risk of developing inflammatory arthritis. After adjusting for smoking and other risk factors, the analysis of data on nearly 26,000 men and women ages 45 to 75 over the course of nine years found a twofold risk among the biggest beef-eaters.
“It may be that the high collagen content of meat leads to collagen sensitization and consequent production of anti-collagen anti-bodies,” said study authors Professors Alan Silman and Deborah Symmons, though they caution that more research is necessary to confirm a causal relationship. This latest finding fleshed out an earlier study that found a higher risk of rheumatoid arthritis among those who ate fruits and vegetables.
As we’ve discussed in previous newsletters, excessive meat consumption also raises your risk of developing non-Hodgkin’s lymphoma and a woman’s risk of developing endometriosis.