Consumption of Fish and Long-chain n-3 Polyunsaturated Fatty Acids Is Associated With Reduced Risk of Colorectal Cancer in a Large European Cohort.

BACKGROUND & AIMS: There is an unclear association between intake of fish and long-chain n-3 polyunsaturated fatty acids (n-3 LC-PUFAs) and colorectal cancer (CRC). We examined the association between fish consumption, dietary and circulating levels of n-3 LC-PUFAs, and ratio of n-6:n-3 LC-PUFA with CRC using data from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. METHODS: Dietary intake of fish (total, fatty/oily, lean/white) and n-3 LC-PUFA were estimated by food frequency questionnaires given to 521,324 participants in the EPIC study; among these, 6291 individuals developed CRC (median follow up, 14.9 years). Levels of phospholipid LC-PUFA were measured by gas chromatography in plasma samples from a sub-group of 461 CRC cases and 461 matched individuals without CRC (controls). Multivariable Cox proportional hazards and conditional logistic regression models were used to calculate hazard ratios (HRs) and odds ratios (ORs), respectively, with 95% CIs. RESULTS: Total intake of fish (HR for quintile 5 vs 1, 0.88; 95% CI, 0.80-0.96; Ptrend = .005), fatty fish (HR for quintile 5 vs 1, 0.90; 95% CI, 0.82-0.98; Ptrend = .009), and lean fish (HR for quintile 5 vs 1, 0.91; 95% CI, 0.83-1.00; Ptrend = .016) were inversely associated with CRC incidence. Intake of total n-3 LC-PUFA (HR for quintile 5 vs 1, 0.86; 95% CI, 0.78-0.95; Ptrend = .010) was also associated with reduced risk of CRC, whereas dietary ratio of n-6:n-3 LC-PUFA was associated with increased risk of CRC (HR for quintile 5 vs 1, 1.31; 95% CI, 1.18-1.45; Ptrend < .001). Plasma levels of phospholipid n-3 LC-PUFA was not associated with overall CRC risk, but an inverse trend was observed for proximal compared with distal colon cancer (Pheterogeneity = .026). CONCLUSIONS: In an analysis of dietary patterns of participants in the EPIC study, we found regular consumption of fish, at recommended levels, to be associated with a lower risk of CRC, possibly through exposure to n-3 LC-PUFA. Levels of n-3 LC-PUFA in plasma were not associated with CRC risk, but there may be differences in risk at different regions of the colon.

Consumption of filtered and boiled coffee and the risk of incident cancer: a prospective cohort study.

BACKGROUND: Despite potentially relevant chemical differences between filtered and boiled coffee, this study is the first to investigate consumption in relation to the risk of incident cancer. METHODS: Subjects were from the Västerbotten Intervention Project (64,603 participants, including 3,034 cases), with up to 15 years of follow-up. Hazard ratios (HR) were calculated by multivariate Cox regression. RESULTS: No associations were found for all cancer sites combined, or for prostate or colorectal cancer. For breast cancer, boiled coffee ≥4 versus <1 occasions/day was associated with a reduced risk (HR = 0.52, CI = 0.30-0.88, p (trend) = 0.247). An increased risk of premenopausal and a reduced risk of postmenopausal breast cancer were found for both total (HR(premenopausal) = 1.69, CI = 0.96-2.98, p (trend) = 0.015, HR(postmenopausal) = 0.60, CI = 0.39-0.93, p (trend) = 0.006) and filtered coffee (HR(premenopausal) = 1.76, CI = 1.04-3.00, p (trend) = 0.045, HR(postmenopausal) = 0.52, CI = 0.30-0.88, p (trend) = 0.045). Boiled coffee was positively associated with the risk of respiratory tract cancer (HR = 1.81, CI = 1.06-3.08, p (trend) = 0.084), a finding limited to men. Main results for less common cancer types included total coffee in renal cell cancer (HR = 0.30, CI = 0.11-0.79, p (trend) = 0.009) and boiled coffee in pancreas cancer (HR = 2.51 CI = 1.15-5.50, p (trend) = 0.006). CONCLUSION: These findings demonstrate, for the first time, the potential relevance of brewing method in investigations of coffee consumption and cancer risk, but they must be confirmed in future studies.