Coffee Consumption and Whole-Blood Gene Expression in the Norwegian Women and Cancer Post-Genome Cohort.

Norwegians are the second highest consumers of coffee in the world. Lately, several studies have suggested that beneficial health effects are associated with coffee consumption. By analyzing whole-blood derived, microarray based mRNA gene expression data from 958 cancer-free women from the Norwegian Women and Cancer Post-Genome Cohort, we assessed the potential associations between coffee consumption and gene expression profiles and elucidated functional interpretation. Of the 958 women included, 132 were considered low coffee consumers (<1 cup of coffee/day), 422 moderate coffee consumers (1⁻3 cups of coffee/day), and 404 were high coffee consumers (>3 cups of coffee/day). At a false discovery rate <0.05, 139 genes were differentially expressed between high and low consumers of coffee. A subgroup of 298 nonsmoking, low tea consumers was established to isolate the effects of coffee from smoking and potential caffeine containing tea consumption. In this subgroup, 297 genes were found to be differentially expressed between high and low coffee consumers. Results indicate differentially expressed genes between high and low consumers of coffee with functional interpretations pointing towards a possible influence on metabolic pathways and inflammation.