Adherence to the Dutch dietary guidelines is inversely associated with 20-year mortality in a large prospective...

The Dutch guidelines for a healthy diet aim to reduce major chronic diseases. However, supporting evidence on their overall association with all-cause and cause-specific mortality is limited. Recently, the Dutch Healthy Diet-index (DHD-index) has been developed to assess adherence to these guidelines. The aim was to examine the association between the DHD-index and all-cause mortality and deaths from cardiovascular disease (CVD), coronary heart disease (CHD), stroke and cancer.

We followed 3593 men and women aged 55 years and older enrolled in the Rotterdam Study, a population-based prospective cohort study, from baseline in 1990-1993 to 2011. A validated 170-item food frequency questionnaire at baseline was used to calculate the DHD-index score (maximum 90 points). Cox proportional hazard models were used to estimate hazard ratios (HRs) adjusting for age, sex, total energy intake, smoking and educational level.

During the 20-year follow-up, 1831 (51%) deaths were reported. Mean DHD-index score was 60.6 (s.d. 10.6). The score was inversely associated with all-cause mortality (highest vs lowest quartile HR 0.77; 95% confidence interval (CI) 0.67, 0.89). Inverse but non-significant associations were observed for mortality due to CVD (HR 0.74; 95% CI 0.55, 1.01), CHD (HR 0.60; 95% CI 0.34, 1.06) and stroke (HR 0.67; 95% CI 0.36, 1.22), whereas no association was observed with cancer mortality (HR 0.99; 95% CI 0.90, 1.11).

A higher level of adherence to the Dutch dietary guidelines, as assessed with the DHD-index, was associated with a lower risk of all-cause mortality, probably due to an inverse association with cardiovascular causes of death.