No Association between Adherence to a Healthy Nordic Food Index and Colorectal Cancer: Results from a Swedish Cohort Study.

Abstract

Recently, the Nordic diet has gained interest, and a healthy Nordic food index has been developed, which has been found inversely related to colorectal cancer among Danish women. This single finding, however, requires replication in other cohorts. We conducted a prospective study in the Women's Lifestyle and Health cohort, including 45,222 women, recruited in 1991-92, and followed up ever since through Swedish registries. Participants were classified according to the Nordic food index (consisting of whole grain bread, oatmeal, apples/pears, cabbages, root vegetables, and fish/shellfish), and the association between adherence and colorectal cancer was assessed using the Cox proportional hazards models. In the fully adjusted models, we found no association, neither with the continuous index score [incidence rate ratio (IRR), 1.04; 95% confidence interval (CI), 0.95-1.12, per 1-point increment] nor in the categorical analyses (IRR, 1.09; 95% CI, 0.78-1.52 for highest vs. lowest adherers). The present study does, thus, not support a previous finding of an inverse association between a healthy Nordic food index and colorectal cancer. This article adds new evidence to the field of the Nordic diet in disease prevention.