The Association of Dietary Quality Indices and Cancer Mortality: A Systematic Review and Meta-analysis of Cohort Studies

This study aimed to systematically review and do a meta-analysis on available evidence on the association of diet quality indices with cancer mortality. We searched for relevant papers published up to August 2017 through Web of science, PubMed/Medline, Scopus, and Google Scholar. Prospective cohort studies examined the association of any dietary quality indices with cancer mortality were included. Overall, 27 publications were included. There was significant inverse associations between the Dietary Approaches to Stop Hypertension (DASH) diet (HR: 0.85; 95% CI: 0.79, 0.91; I-2=81.8%), the Alternative Healthy Eating Index (AHEI) (HR: 0.90; 95% CI: 0.85, 0.95; I-2: 61.5), the healthy eating index (HEI) (RR: 0.82; 95% CI: 0.75, 0.89; I-2: 89.5%) and cancer mortality. Significant associations with the lowest heterogeneity between Diet Quality Index (DQI) (HR: 0.91; 95% CI: 0.89-0.93, I-2=0.0%), alternative Mediterranean Diet (aMED) (RR: 0.81; 95% CI: 0.78-0.83, I-2=1.7%), and HEI-2010 (HR: 0.82; 95% CI: 0.69-0.98, I-2=0.0%) and death due to cancer were also found. However, the Recommended Food Score, Dietary Diversity Score (DDS), and HEI-2005 were not related with cancer mortality. Adherence to DASH diet, AHEI, HEI, DQI, aMED, and HEI-2010 decreased the risk of cancer mortality.