BACKGROUND: Epidemiological findings are controversial relating to the relationship between dietary folate intake and the risk of breast cancer. We therefore conducted a meta-analysis of prospective cohort studies to clarify this association. MATERIALS AND METHODS: PUPMED, EMBASE, and MEDLINE databases were searched for all relevant literature published in English from January 1, 1966 to August 2013. Summary relative risk (RR) and 95% confidence intervals (CIs) were calculated using a fixed or random effects model. RESULTS: Dietary folate intake was not significantly associated with the risk of breast cancer. The combined PR with 95% CI for the highest vs. lowest category dietary intake of folate [fifteen studies; 1,836,566 participants and 24,083 patients with breast cancer] was 0.98 (0.90-1.05). Among subgroup analysis by menstrual status, hormonal status and the consumption of alcohol, methionine and vitamin B12, no significant association was observed for the dietary intake of folate and the risk of breast cancer. Dose-response analysis showed that a 220 μg/day increment in dietary folate intake was not associated with the risk of breast cancer. CONCLUSIONS: Our findings indicate that dietary folate intake has no significant effect on the risk of breast cancer.
BACKGROUND: Epidemiological findings are controversial relating to the relationship between dietary folate intake and the risk of breast cancer. We therefore conducted a meta-analysis of prospective cohort studies to clarify this association. MATERIALS AND METHODS: PUPMED, EMBASE, and MEDLINE databases were searched for all relevant literature published in English from January 1, 1966 to August 2013. Summary relative risk (RR) and 95% confidence intervals (CIs) were calculated using a fixed or random effects model. RESULTS: Dietary folate intake was not significantly associated with the risk of breast cancer. The combined PR with 95% CI for the highest vs. lowest category dietary intake of folate [fifteen studies; 1,836,566 participants and 24,083 patients with breast cancer] was 0.98 (0.90-1.05). Among subgroup analysis by menstrual status, hormonal status and the consumption of alcohol, methionine and vitamin B12, no significant association was observed for the dietary intake of folate and the risk of breast cancer. Dose-response analysis showed that a 220 μg/day increment in dietary folate intake was not associated with the risk of breast cancer. CONCLUSIONS: Our findings indicate that dietary folate intake has no significant effect on the risk of breast cancer.
Authors: Heleen Van Puyvelde; Nikos Papadimitriou; Joanna Clasen; David Muller; Carine Biessy; Pietro Ferrari; Jytte Halkjær; Kim Overvad; Anne Tjønneland; Renée T Fortner; Verena Katzke; Matthias B Schulze; Paolo Chiodini; Giovanna Masala; Valeria Pala; Carlotta Sacerdote; Rosario Tumino; Marije F Bakker; Antonio Agudo; Eva Ardanaz; María Dolores Chirlaque López; Maria-Jose Sánchez; Ulrika Ericson; Björn Gylling; Therese Karlsson; Jonas Manjer; Julie A Schmidt; Geneviève Nicolas; Corinne Casagrande; Elisabete Weiderpass; Alicia K Heath; Lode Godderis; Koen Van Herck; Dirk De Bacquer; Marc J Gunter; Inge Huybrechts Journal: Nutrients Date: 2021-05-28 Impact factor: 5.717