Adherence to dietary guidelines and 15-year risk of all-cause mortality.

Past investigation of diet in relation to disease or mortality has tended to focus on individual nutrients. However, there has been a recent shift to now focus on overall patterns of food intake. The present study aims to investigate the relationship between diet quality reflecting adherence to dietary guidelines and mortality in a sample of older Australians, and to report on the relationship between core food groups and diet quality. This was a population-based cohort study of persons aged 49 years or older at baseline, living in two postcode areas west of Sydney, Australia. Baseline dietary data were collected during 1992-4, from 2897 people using a 145-item Willett-derived FFQ. A modified version of the Healthy Eating Index for Australians was developed to determine diet quality scores. The Australian National Death Index provided 15-year mortality data using multiple data linkage steps. Hazard risk (HR) ratios and 95 % CI for mortality were assessed for diet quality. Subjects in quintile 5 (highest) of the Total Diet Score had a 21 % reduced risk of all-cause mortality (HR 0·79, 95 % CI 0·63, 0·98, P(trend)=0·04) compared with those in quintile 1 (lowest) after multivariate adjustment. The present study provides longitudinal support for a reduced risk of all-cause mortality in an older population who have greater compliance with published dietary guidelines.