Red meat, chicken, and fish consumption and risk of colorectal cancer.
BACKGROUND
Red meat and processed meat consumption have been associated with increased risk of colorectal cancer in some, but not all, relevant cohort studies. Evidence on the relationship between risk of colorectal cancer and poultry and fish consumption is inconsistent.


METHODS
We conducted a prospective cohort study of 37,112 residents of Melbourne, Australia recruited from 1990 to 1994. Diet was measured with a food frequency questionnaire. We categorized the frequency of fresh red meat, processed meat, chicken, and fish consumption into approximate quartiles. Adenocarcinomas of the colon or rectum were ascertained via the Victorian Cancer Registry.


RESULTS
We identified 283 colon cancers and 169 rectal cancers in an average of 9 years of follow-up. For rectal cancer, the hazard ratios [95% confidence intervals (95% CI)] in the highest quartile of consumption of fresh red meat and processed meat were 2.3 (1.2-4.2; P for trend = 0.07) and 2.0 (1.1-3.4; P for trend = 0.09), respectively. The corresponding hazard ratios (95% CIs) for colon cancer were 1.1 (0.7-1.6; P for trend = 0.9) and 1.3 (0.9-1.9; P for trend = 0.06). However, for neither type of meat was the heterogeneity between subsites significant. Chicken consumption was weakly negatively associated with colorectal cancer (hazard ratio highest quartile, 0.7; 95% CI, 0.6-1.0; P for trend = 0.03), whereas hazard ratios for fish consumption were close to unity.


CONCLUSIONS
Consumption of fresh red meat and processed meat seemed to be associated with an increased risk of rectal cancer. Consumption of chicken and fish did not increase risk.
English
Dallas R
DR
Cancer Epidemiology Centre, The Cancer Council Victoria, Melbourne, Victoria, Australia. dallas.english@cancervic.org.au
MacInnis
Robert J
RJ
Hodge
Allison M
AM
Hopper
John L
JL
Haydon
Andrew M
AM
Giles
Graham G
GG
D000328:Adult; D000368:Aged; D000818:Animals; D002417:Cattle; D015984:Causality; D002645:Chickens; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D005247:Feeding Behavior; D005260:Female; D005399:Fishes; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008460:Meat; D008461:Meat Products; D008875:Middle Aged; D009749:Nutrition Surveys; D011200:Poultry; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D013223:Statistics as Topic; D014739:Victoria