Research

Mixed

Higher overall diet quality, as measured by adherence to national dietary guidelines or specific scoring indices (e.g., HEI, MDS), is consistently associated with a reduced risk of all-cause mortality, cardiovascular disease (CVD), and certain cancers.

Adhere to established national dietary guidelines by focusing on the quality and variety of your entire diet rather than isolating single nutrients. Higher adherence to these patterns (measured by indices like HEI or MDS) is consistently linked to lower risks of death, heart disease, and cancer. Prioritize fruits, vegetables, whole grains, and healthy fats while limiting processed foods and excess saturated fats.

ModerateSupportsMEDIUM confidence
The majority of studies reviewed had methodological weaknesses but demonstrated that higher dietary quality was consistently inversely related to all-cause mortality, with a protective effect of moderate magnitude. The associations were stronger for men and for all-cause and CVD mortality.
Annika Wirt et al. · Public Health Nutrition · 2009

Why this rating

The review includes 28 studies, mostly observational/cohort, with noted methodological weaknesses and potential confounding, but consistent inverse associations.

Source

Diet quality – what is it and does it matter?

Annika Wirt et al. · Public Health Nutrition · 2009

DOI 10.1017/s136898000900531x

systematic_reviewCited 547×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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