Dietary Intake of N-3 and N-6 Polyunsaturated Fatty Acids and Risk of Cancer: Meta-Analysis of Data from 32 Studies

A partir d'une revue systématique de la littérature publiée jusqu'en mars 2019 (32 études, 1 445 732 participants), cette méta-analyse évalue l'association entre un apport alimentaire en acides gras polyinsaturés à longue chaîne n-3 ou n-6 et le risque de cancer colorectal, de cancer du sein et de la prostate

Résumé en anglais

Background: Large epidemiological studies have yielded conflicting results regarding the relationship between polyunsaturated fatty acids (PUFAs) and cancers. Here, we performed a meta-analysis to examine the link between dietary intake of n-3 and n-6 PUFAs and cancer risk.

Materials and methods: We performed a search on PubMed, EMBASE, and the Cochrane Library. Studies that reported adjusted relative risk (RR) estimates with 95% confidence intervals (CI) for the associations of interest were included.

Results: Thirty-two studies involving 1,445,732 participants were included. Colorectal, breast and prostate cancer had been analyzed in our study. Specifically, for colorectal cancer, total n-3 PUFAs, marine n-3 PUFAs, α-linolenic acids (ALA) and n-6 PUFAs were not associated with the risk of it (RR 1.04, 95%CI 0.85?1.28; RR 0.99, 95%CI 0.89?1.09; RR 1.05, 95%CI 0.93?1.19; RR 1.02, 95%CI 0.94?1.11, respectively). For breast cancer, only marine n-3 PUFAs, but not total n-3 PUFAs, ALA, and n-6 PUFAs, was associated with a lower risk of it (RR 0.70, 95%CI 0.55?0.91). For prostate cancer, ALA and n-6 PUFAs also have no association with the risk of it.

Conclusions: Most subtypes of PUFAs are probably not related to cancers. However, additional high-quality trials are warranted to corroborate the findings of this meta-analysis.