Meat consumption and the risk of incident distal colon and rectal adenoma

Br J Cancer. 2012 Jan 31;106(3):608-16. doi: 10.1038/bjc.2011.549. Epub 2011 Dec 13.

Abstract

Background: Most studies of meat and colorectal adenoma have investigated prevalent events from a single screening, thus limiting our understanding of the role of meat and meat-related exposures in early colorectal carcinogenesis.

Methods: Among participants in the screening arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial who underwent baseline and follow-up sigmoidoscopy (n=17,072), we identified 1008 individuals with incident distal colorectal adenoma. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations between meat and meat-related components and incident distal colorectal adenoma using multivariate logistic regression.

Results: We observed suggestive positive associations for red meat, processed meat, haeme iron, and nitrate/nitrite with distal colorectal adenoma. Grilled meat (OR=1.56, 95% CI=1.04-2.36), well or very well-done meat (OR=1.59, 95% CI=1.05-2.43), 2-amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP) (OR=1.75, 95% CI=1.17-2.64), benzo[a]pyrene (OR=1.53, 95% CI=1.06-2.20), and total mutagenic activity (OR=1.57, 95% CI=1.03-2.40) were positively associated with rectal adenoma. Total iron (diet and supplements) (OR=0.69, 95% CI=0.56-0.86) and iron from supplements (OR=0.65, 95% CI=0.44-0.97) were inversely associated with any distal colorectal adenoma.

Conclusion: Our findings indicate that several meat-related components may be most relevant to early neoplasia in the rectum. In contrast, total iron and iron from supplements were inversely associated with any distal colorectal adenoma.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Adenoma / epidemiology*
  • Adenoma / etiology
  • Aged
  • Colon / pathology
  • Colorectal Neoplasms / epidemiology*
  • Colorectal Neoplasms / etiology
  • Colorectal Neoplasms / prevention & control
  • Female
  • Humans
  • Incidence
  • Male
  • Meat*
  • Middle Aged
  • Risk Factors
  • Sigmoidoscopy
  • United States / epidemiology