Our data confirm that colorectal cancer risk is positively associated with high consumption of red and processed meat and support an inverse association with fish intake.

Objective To examine the association between prediagnostic circulating vitamin D concentration, dietary intake of vitamin D and calcium, and the risk of colorectal cancer in European populations. Design Nested case-control study. Setting The study was conducted within the EPIC study, a cohort of more than 520 000 participants from 10 western European countries. Participants 1248 cases of incident colorectal cancer, which developed after enrolment into the cohort, were matched to 1248 controls Main outcome measures Circulating vitamin D concentration (25-hydroxy-vitamin-D, 25-(OH)D) was measured by enzyme immunoassay. Dietary and lifestyle data were obtained from questionnaires. Incidence rate ratios and 95% confidence intervals for the risk of colorectal cancer by 25-(OH)D concentration and levels of dietary calcium and vitamin D intake were estimated from multivariate conditional logistic regression models, with adjustment for potential dietary and other confounders. Results 25-(OH)D concentration showed a strong inverse linear dose-response association with risk of colorectal cancer (P for trend <0.001). Compared with a pre-defined mid-level concentration of 25-(OH)D (50.0-75.0 nmol/l), lower levels were associated with higher colorectal cancer risk (<25.0 nmol/l: incidence rate ratio 1.32 (95% confidence interval 0.87 to 2.01); 25.0-49.9 nmol/l: 1.28 (1.05 to 1.56), and higher concentrations associated with lower risk (75.0-99.9 nmol/l: 0.88 (0.68 to 1.13); ≥100.0 nmol/l: 0.77 (0.56 to 1.06)). In analyses by quintile of 25-(OH)D concentration, patients in the highest quintile had a 40% lower risk of colorectal cancer than did those in the lowest quintile (P<0.001). Subgroup analyses showed a strong association for colon but not rectal cancer (P for heterogeneity=0.048). Greater dietary intake of calcium was associated with a lower colorectal cancer risk. Dietary vitamin D was not associated with disease risk. Findings did not vary by sex and were not altered by corrections for season or month of blood donation. Conclusions The results of this large observational study indicate a strong inverse association between levels of pre-diagnostic 25-(OH)D concentration and risk of colorectal cancer in western European populations. Further randomised trials are needed to assess whether increases in circulating 25-(OH)D concentration can effectively decrease the risk of colorectal cancer.

Importance Low-density lipoprotein (LDL) cholesterol-lowering alleles in or near NPC1L1 or HMGCR, encoding the respective molecular targets of ezetimibe and statins, have previously been used as proxies to study the efficacy of these lipid-lowering drugs. Alleles near HMGCR are associated with a higher risk of type 2 diabetes, mimicking the increased incidence of new-onset diabetes associated with statin treatment in randomized clinical trials. It is unknown whether alleles near NPC1L1 are also associated with the risk of type 2 diabetes. Objective To investigate whether LDL-lowering alleles in or near NPC1L1 and other genes encoding current or prospective molecular targets of lipid-lowering therapy (i.e. HMGCR, PCSK9, ABCG5/G8, LDLR) are associated with the risk of type 2 diabetes. Design, Setting and Participants The associations with type 2 diabetes and coronary artery disease of LDL-lowering genetic variants were investigated in meta-analyses of genetic association studies. Meta-analyses included 50,775 individuals with type 2 diabetes and 270,269 controls including three studies and 60,801 individuals with coronary artery disease and 123,504 controls from a published meta-analysis. Data collection took place in Europe and the United States between 1991 and 2016. Exposure LDL-lowering alleles in or near NPC1L1, HMGCR, PCSK9, ABCG5/G8, LDLR. Main Outcomes and Measures Odds ratio of type 2 diabetes and coronary artery disease. Results LDL-lowering genetic variants at NPC1L1 were inversely associated with coronary artery disease (odds ratio for a genetically-predicted reduction of 1 mmol/L in LDL cholesterol, 0.61; 95% confidence interval, 0.42-0.88; p=0.008) and directly associated with type 2 diabetes (2.42, 1.70-3.43; p<0.001). The odds ratio of type 2 diabetes for PCSK9 genetic variants was 1.19 (95% confidence interval, 1.02-1.38, p=0.03). For a given reduction in LDL cholesterol, genetic variants were associated with a similar reduction in coronary artery disease risk (I-squared for heterogeneity in genetic associations=0.0%; p=0.93). However, associations with type 2 diabetes were heterogeneous (I-squared=77.2%; p=0.002), indicating gene-specific associations with metabolic risk for LDL-lowering alleles. Conclusions and Relevance In this meta-analysis, exposure to LDL-cholesterol lowering genetic variants in or near NPC1L1 and other genes was associated with a higher risk of type 2 diabetes. These data provide insights into potential adverse effects of LDL cholesterol-lowering therapy.