A prospective analysis of red and processed meat consumption and risk of colorectal cancer in women

Abstract

Background: Red and processed meats have been implicated as risk factors in the development of colorectal cancer (CRC) in U.S. women, but associations with cooking practices are less well established. Methods: Data are from the Sister Study, a cohort of women 35-74 years old from U.S. and Puerto Rico who have a sister diagnosed with breast cancer. Red and processed meat consumption, meat cooking practices, and intake of common meat products were collected at baseline using self-administered questionnaires (N=48,704). Multivariable hazard ratios (HRadj) and 95% confidence intervals (95%CIs) were estimated. Results: During a median 8.7 years follow-up (range <1-12.7 years), 216 CRC cases were diagnosed. In categorical analyses, an increased risk of CRC was seen in the highest quartile of processed meat consumption compared to the lowest [HRadj=1.52 (95%CI: 1.01-2.30); p-trend: 0.02], and for specific meat products, including breakfast sausages (HRadj=1.85 [95%CI: 1.30-2.64]) and bacon (HRadj=1.46 [95%CI: 1.01-2.11]). The adjusted HR for the highest quartile of red meat consumption was 1.04 (95%CI: 0.68-1.60), and little evidence of association was observed for cooking practices or doneness of red meat. We observed positive associations with specific red meat products when cooking methods were considered; e.g., grilled/ barbequed steaks (HRadj=2.23 [95%CI: 1.20-4.14]) and hamburgers (HRadj=1.98 [95%CI: 1.00-3.91]). Conclusions: Higher reported daily intake of processed meats and consumption of barbecued/grilled red meat products were associated with increased risk of CRC in women. Impact: Variability in CRC risk by meat type and cooking method should be considered when evaluating meat consumption.