title: Dietary alpha-linolenic acid is associated with reduced risk of fatal coronary heart disease, but increased prostate cancer risk: a meta-analysis.
abstract: The objective of this meta-analysis was to estimate quantitatively the associations between intake of alpha-linolenic acid [ALA, the (n-3) fatty acid in vegetable oils], mortality from heart disease, and the occurrence of prostate cancer in observational studies. We identified 5 prospective cohort studies that reported intake of ALA and mortality from heart disease. We also reviewed data from 3 clinical trials on ALA intake and heart disease. In addition, we identified 9 cohort and case-control studies that reported on the association between ALA intake or blood levels and incidence or prevalence of prostate cancer. We combined risk estimates across studies using a random-effects model. High ALA intake was associated with reduced risk of fatal heart disease in prospective cohort studies (combined relative risk 0.79, 95% CI 0.60-1.04). Three open-label trials also indicated that ALA may protect against heart disease. However, epidemiologic studies also showed an increased risk of prostate cancer in men with a high intake or blood level of ALA (combined relative risk 1.70; 95% CI 1.12-2.58). This meta-analysis shows that consumption of ALA might reduce heart disease mortality. However, the association between high intake of ALA and prostate cancer is of concern and warrants further study.
authors.affiliation: Wageningen Centre for Food Sciences, Wageningen, the Netherlands. ingeborg.brouwer@wur.nl
authors.forename: Ingeborg A
authors.initials: IA
authors.lastname: Brouwer
authors.forename: Martijn B
authors.initials: MB
authors.lastname: Katan
authors.forename: Peter L
authors.initials: PL
authors.lastname: Zock
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002986:Clinical Trials as Topic; D015331:Cohort Studies; D003327:Coronary Disease / Q000401:mortality* / Q000517:prevention & control; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D016239:MEDLINE; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D017962:alpha-Linolenic Acid / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood
chemical_list: D004042:Dietary Fats, Unsaturated; D017962:alpha-Linolenic Acid