Dietary vitamin D intake and colorectal cancer risk: a longitudinal approach within the PREDIMED study.

PURPOSE: We evaluated whether the intake of dietary vitamin D is associated with the incidence of both colorectal cancer (CRC) and colon cancer in the framework of the PREDIMED cohort of older adults at high cardiovascular risk. METHODS: We analyzed data from 7216 men and women (55-80 years) without CRC at baseline from the PREvención con DIeta MEDiterránea study. Baseline consumption of vitamin D was assessed using a validated 137-item food frequency questionnaire. Cox proportional hazards ratios (HRs) of CRC and colon cancer incidence were estimated for quartiles and per 1-SD of baseline vitamin D intake. RESULTS: During a median follow-up of 6 years, we documented 97 incident CRC cases after the exclusion of subjects with no baseline dietary data and/or outliers of energy intake. A non-significant HRs and 95% confidence intervals (CIs) of CRC for the comparison of extreme quartiles (4th vs 1st) of vitamin D intake were observed [0.55 (0.30-1.00), P for trend = 0.072], whereas it was significant for colon cancer incidence alone [0.44 (0.22-0.90), P for trend = 0.032]. However, this association became significant in CRC and colon cancer incidence, after excluding 391 subjects consuming baseline vitamin D and/or calcium medication or prescribed supplements [0.52 (0.28-0.96) and 0.41 (0.12-0.85), respectively]. CONCLUSION: A higher dietary intake of vitamin D was significantly associated with a reduced CRC risk in individuals at high cardiovascular risk.

Nutritional adequacy according to carbohydrates and fat quality.

PURPOSE: To investigate the association between carbohydrate quality, fat quality or adherence to the Mediterranean diet and intake adequacy of 19 micronutrients in the PREDIMED (PREvención con DIeta MEDiterránea) trial, a multicenter, randomized, controlled, parallel group and primary prevention trial conducted in Spain. METHODS: We assessed baseline dietary intake of 6,542 elderly subjects at high cardiovascular risk through a validated food frequency questionnaire (FFQ) and a validated 14-item Mediterranean diet (Med-diet) score. We used a multidimensional carbohydrate quality index (CQI) using four criteria and a fat quality index (FQI) according to the ratio (MUFA + PUFA)/(SFA + TFA). The probability of intake adequacy was calculated comparing the intakes to DRI, and also using the probabilistic approach. Absolute and adjusted probability of having inadequate intake for either ≥6 DRI or ≥8 DRI were estimated to assess nutritional adequacy according to quintiles of each index. RESULTS: The lowest prevalence of inadequate micronutrient intake (≥8 DRI) was found in the highest quintile of CQI or Med-diet score, and in the lowest quintile of FQI (adjusted fold risk: 1.4, 3.4 and 10.2 respectively in comparison with the lowest quintile). P for trend <0.001 in three multivariable models. A higher CQI or Med-Diet score and a lower FQI were significantly associated with a lower fold risk of unmet EAR values. CONCLUSIONS: A multidimensional assessment of CQI can be a useful tool to evaluate the quality of carbohydrates. This score and a 14-item Med-diet score were positively related to overall micronutrient adequacy in elderly participants.