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Background: Cereal‐derived polyphenols have demonstrated protective mechanisms in colorectal cancer (CRC) models; however, confirmation in human studies is lacking. Therefore, this study examined the association between cereal polyphenol intakes and CRC risk in the Melbourne Collaborative Cohort Study (MCCS), a prospective cohort study in Melbourne, Australia that recruited participants between 1990 and 1994 to investigate diet–disease relationships. Methods: Using food frequency questionnaire diet data matched to polyphenol data, dietary intakes of alkylresorcinols, phenolic acids, lignans, and total polyphenols from cereals were estimated. Hazard ratios (HRs) and 95% confidence intervals for CRC risk were estimated for quintiles of intake with the lowest quintile as the comparison category, using multivariable adjusted Cox proportional hazards models with age as the time axis adjusted for sex, socio‐economic status, alcohol consumption, fibre intake, country of birth, total energy intake, physical activity and smoking status. Results: From 35,245 eligible adults, mean (SD) age 54.7 (8.6) years, mostly female (61%) and Australian‐born (69%), there were 1394 incident cases of CRC (946 colon cancers and 448 rectal cancers). Results for total cereal polyphenol intake showed reduced HRs in Q2 (HR: 0.80; 95% CI, 0.68–0.95) and Q4 (HR: 0.75; 95% CI, 0.62–0.90), and similar for phenolic acids. Alkylresorcinol intake showed reduced HR in Q3 (HR: 0.80; 95% CI, 0.67–0.95) and Q4 (HR: 0.79; 95% CI, 0.66–0.95). Conclusions: Overall, the present study showed little evidence of association between intakes of cereal polyphenols and CRC risk. Future investigations may be useful to understand associations between cereal‐derived polyphenols and additional cancers in different populations. [ABSTRACT FROM AUTHOR]

Objective: To investigate relationships between mortality and circulating 25-hydroxyvitamin D (25(OH)D), 25-hydroxycholecalciferol (25(OH)D3) and 25-hydroxyergocalciferol (25(OH)D2).Design: Case-cohort study within the Melbourne Collaborative Cohort Study (MCCS). We measured 25(OH)D2 and 25(OH)D3 in archived dried blood spots by LC-MS/MS. Cox regression was used to estimate mortality hazard ratios (HR), with adjustment for confounders.Setting: General community.Subjects: The MCCS included 29 206 participants, who at recruitment in 1990-1994 were aged 40-69 years, had dried blood spots collected and no history of cancer. For the present study we selected participants who died by 31 December 2007 (n 2410) and a random sample (sub-cohort, n 2996).Results: The HR per 25 nmol/l increment in concentration of 25(OH)D and 25(OH)D3 were 0·86 (95 % CI 0·78, 0·96; P=0·007) and 0·85 (95 % CI 0·77, 0·95; P=0·003), respectively. Of 5108 participants, sixty-three (1·2 %) had detectable 25(OH)D2; their mean 25(OH)D concentration was 11·9 (95 % CI 7·3, 16·6) nmol/l higher (P<0·001). The HR for detectable 25(OH)D2 was 1·80 (95 % CI 1·09, 2·97; P=0·023); for those with detectable 25(OH)D2, the HR per 25 nmol/l increment in 25(OH)D was 1·06 (95 % CI 0·87, 1·29; P interaction=0·02). HR were similar for participants who reported being in good, very good or excellent health four years after recruitment.Conclusions: Total 25(OH)D and 25(OH)D3 concentrations were inversely associated with mortality. The finding that the inverse association for 25(OH)D was restricted to those with no detectable 25(OH)D2 requires confirmation in populations with higher exposure to ergocalciferol. [ABSTRACT FROM AUTHOR]

Objective: To evaluate FFQ estimates of dietary intake of individual antioxidants, fruit and vegetables in comparison to plasma concentrations of each antioxidant, and to determine which individual foods are associated with plasma antioxidant concentrations. Design: Dietary (α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, lycopene, retinol, and vitamin E) intakes over 12 months were estimated from a 121-item FFQ. Correlation coefficients, corrected for within-person variability in diet and plasma antioxidants, were used to examine associations between antioxidant concentrations in diet and plasma. Setting: Melbourne Collaborative Cohort Study (MCCS). Subjects: Men and women (n 3110) who were randomly selected from the MCCS. Participants were aged 36-72 years and were born in Australia, Greece, Italy or the UK. Results: Correlation coefficients for the carotenoids ranged from 0·28 for lycopene to 0·46 for b-cryptoxanthin. There was no association between dietary and plasma retinol or dietary vitamin E with plasma α- and γ-tocopherol. Individual plasma carotenoid concentrations were associated with intakes of fruit and vegetables. Conclusions: Our data suggest that the FFQ provides useful information on intakes of each of the carotenoids: α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin. There was no association between diet and plasma markers of retinol or vitamin E; this may reflect the importance of factors other than intake in modifying circulating levels of these nutrients. [ABSTRACT FROM AUTHOR]