Red Blood Cell Fatty Acids and Risk of Colorectal Cancer in The European Prospective Investigation into Cancer and Nutrition (EPIC).

BACKGROUND: A growing body of evidence suggests that alterations of dietary fatty acid (FA) profiles are associated with colorectal cancer risk. However, data from large-scale epidemiologic studies using circulating FA measurements to objectively assess individual FA and FA categories are scarce. METHODS: We investigate the association between red blood cell (RBC) membrane FAs and risk of colorectal cancer in a case-control study nested within a large prospective cohort. After a median follow-up of 6.4 years, 1,069 incident colorectal cancer cases were identified and matched to 1,069 controls among participants of the European Prospective Investigation into Cancer and Nutrition (EPIC). The FA composition of RBC phospholipids (in mol%) was analyzed by gas chromatography, and their association with risk of colorectal cancer was estimated by multivariable adjusted conditional logistic regression models. RESULTS: After correction for multiple testing, subjects with higher concentrations of RBC stearic acid were at higher risk for colorectal cancer (OR = 1.23; 95% CI = 1.07-1.42, per 1 mol%). Conversely, colorectal cancer incidence decreased with increasing proportions of RBC n-3 PUFA, particularly eicosapentaenoic acid (0.75; 0.62-0.92, per 1 mol%). The findings for the n-6 PUFA arachidonic acid were inconsistent. CONCLUSIONS: The positive association between prediagnostic RBC stearic acid and colorectal cancer reflects putative differences in FA intake and metabolism between cancer cases and matched controls, which deserve further investigation. The inverse relationship between EPA and colorectal cancer is in line with the repeatedly reported protective effect of fish consumption on colorectal cancer risk. IMPACT: These findings add to the evidence on colorectal cancer prevention.

Usual Dietary Intake Estimation Based on a Combination of Repeated 24-H Food Lists and a Food Frequency Questionnaire in the KORA FF4 Cross-Sectional Study.

Background: Estimation of usual dietary intake poses a challenge in epidemiological studies. We applied a blended approach that combines the strengths provided by repeated 24-h food lists (24HFLs) and a food frequency questionnaire (FFQ). Methods: At least two web-based 24HFLs and one FFQ were completed by 821 participants in the KORA FF4 study. Consumption probabilities were estimated using logistic mixed models, adjusting for covariates and the FFQ data on consumption frequency. Intake amount of a consumed food item was predicted for each participant based on the results of the second Bavarian Food Consumption Survey (BVS II). By combining consumption probability and estimated consumption amount, the usual food intake for each participant was estimated. These results were compared to results obtained without considering FFQ information for consumption probability estimation, as well as to conventional FFQ data. Results: The results of the blended approach for food group intake were often higher than the FFQ-based results. Intraclass correlation coefficients between both methods ranged between 0.21 and 0.86. Comparison of both methods resulted in weighted kappa values based on quintiles ranging from fair (0.34) to excellent agreement (0.84). Omission of FFQ information in the consumption probability models distinctly affected the results at the group level, though individual intake data were slightly affected, for the most part. Conclusions: Usual dietary intake data based on the blended approach differs from the FFQ-based results both in absolute terms and in classification according to quintiles. The application of the blended approach has been demonstrated as a possible tool in nutritional epidemiology, as a comparison with published studies showed that the blended approach yields reasonable estimates. The inclusion of the FFQ information is valuable especially with regard to irregularly consumed foods. A validation study including biomarkers of dietary intake is warranted.

Long-term reproducibility of a food-frequency questionnaire and dietary changes in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort.

Within a prospective cohort study, we explored the long-term reproducibility of the food-frequency questionnaire (FFQ) and dietary changes in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort. After a mean follow-up time of 68.8 (sd 4.1) months the dietary assessment by means of a validated FFQ was repeated in 21,462 participants in the EPIC-Heidelberg cohort. The correlation and test-retest reproducibility of both dietary intake measurements was explored. The long-term correlation coefficients ranged from 0.41 (vegetables in men) to 0.77 (alcoholic beverage consumption in women). The median intake of potatoes, added fat, sugar/confectionary, cakes and alcoholic beverages was lower in the second than in the first FFQ, whereas the median intake of fruits, vegetables, cereals/cereal products and non-alcoholic beverages were higher. Consistently for food groups, 60-70 % of the participants in both genders were re-classified to the same or adjacent quintile of intake. The results of fairly high correlation coefficients indicate good agreement between both measurements. It is acknowledged that this result reflects to a substantial extent the measurement error of the FFQ and conclusions on real changes in the diet should be drawn very carefully. For some nutrients the dietary changes were consistent with results from independent national surveys. The performance of the FFQ gives confidence in the dietary data to be used as long-term exposure variables.

Intake of heterocyclic aromatic amines from meat in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg cohort.

It was the aim of the present study to estimate the intake of heterocyclic aromatic amines (HCA) from meat, which have been associated with cancer risk in several epidemiological studies, of 21 462 subjects who participated in the European Prospective Investigation into Cancer and Nutrition (EPIC) in Heidelberg. This was accomplished by using a detailed dietary questionnaire that assessed meat consumption, cooking methods, and degree of browning of the respective food items. Median total HCA intake from meat was 31 ng/d (mean 69 ng/d), which was lower than results observed in previous studies. 2-Amino-1-methyl-6-phenylimidazo[4,5b]pyridine was the most common HCA in this cohort (median 17; mean 48 ng/d). The present study offers the opportunity of a detailed examination of the associations between meat cooking as well as HCA intake from meat and cancer risk in a prospective way.