Associations between an overall, healthful, and unhealthful low-fat dietary patterns and breast cancer risk in a Mediterranean cohort: the SUN project
Menée à partir des données 1999-2019 de l'étude "the SUN project" portant sur 10 930 femmes (âge moyen : 35,2 ans ; durée médiane de suivi : 12,1 ans), cette étude analyse l'association entre la qualité de différents régimes alimentaires pauvres en graisse et le risque de cancer du sein (150 cas), en fonction du statut ménopausique
Objective: Dietary patterns may have a greater influence on human health than individual foods or nutrients and they are also of substantial interest in the field of breast cancer prevention. Beyond the adequate balance of macronutrients, evidence shows that the quality of macronutrient sources may play an important role in health outcomes. We sought to examine the relationship between a healthful and an unhealthful low-fat dietary pattern in relation to breast cancer. Methods: We used an observational data from a Mediterranean cohort study (the SUN project). We prospectively followed 10,930 middle-aged women initially free of breast cancer during a median follow-up of 12.1 years. We calculated an overall, an unhealthful, and a healthful low-fat-diet score proposed by Shan et al., based on a previously validated 136-item FFQ and grouped participants into tertiles. Incident breast cancer –overall and stratified by menopausal status– was the primary outcome. It was self-reported by participants and confirmed based on medical reports or consultation of the National death index. We used multivariable Cox regression models adjusted for potential confounders. Results: During 123,297 person-years of follow-up, 150 cases of incident breast cancer were confirmed. No significant associations were observed for overall or premenopausal breast cancer. For postmenopausal women, we observed a significant association for moderate adherence to the unhealthful LFD score and postmenopausal breast cancer (comparing tertile 2 vs. tertile 1, HR= 2.18; 95% confidence interval, 1.15–4.13) Conclusion: In conclusion, no clear associations were observed although more research is needed to address the association between an unhealthful dietary pattern and postmenopausal breast cancer risk.