REVIEW ARTICLE A Systematic Review of the Evidence Supporting a Causal Link Between Dietary Factors and Coronary Heart Disease

Background: Although a wealth of literature links di-etary factors andcoronaryheart disease (CHD), the strength of the evidence supporting valid associations has not been evaluated systematically in a single investigation. Methods: We conducted a systematic search of MEDLINE for prospective cohort studies or random-ized trials investigating dietary exposures in relation to CHD. We used the Bradford Hill guidelines to derive a causation score based on 4 criteria (strength, consis-tency, temporality, and coherence) for each dietary ex-posure in cohort studies and examined for consistency with the findings of randomized trials. Results:Strongevidencesupportsvalidassociations(4cri-teria satisfied)ofprotective factors, including intakeofveg-etables,nuts, and“Mediterranean”andhigh-qualitydietar