title: Fish, n - 3 polyunsaturated fatty acids and n - 6 polyunsaturated fatty acids intake and breast cancer risk: The Japan Public Health Center-based prospective study.
abstract: Limited and inconsistent studies exist on the association between the intake of fish, n - 3 polyunsaturated fatty acids (PUFA) and n - 6 PUFA and breast cancer. Fish and n - 3 PUFA support various body functions and are thought to reduce the carcinogenesis risk while n - 6 PUFA may have a positive association with cancer risk. We examined the association between intake of fish, n - 3 PUFA [including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA) and alpha-linolenic acid (ALA)] and n - 6 PUFA and breast cancer with subanalyses on estrogen (ER) and progesterone receptor (PR) status. We investigated 38,234 Japanese women aged 45-74 years from the Japan Public Health Center-based prospective study (JPHC study), and during 14.1 years of follow-up time, 556 breast cancer cases were newly diagnosed. Breast cancer risk was not associated with the intake of total fish, n - 3 PUFA and n - 6 PUFA when analyzed in totality through multivariable Cox proportional hazards regression models with age as the time scale. Intake of total n - 6 was positively associated with the development of ER+PR+ tumors [multivariable-adjusted HR Q4 vs. Q1  = 2.94 (95% CI: 1.26-6.89; ptrend  = 0.02)]. Intake of EPA was associated with a decreased breast cancer risk for ER+PR+ tumors [multivariable-adjusted HR Q2 vs. Q1  = 0.47 (95% CI: 0.25-0.89; ptrend =0.47)]. While the overall association between the intake of total fish, n - 3 PUFA and n - 6 PUFA and breast cancer risk is null, for ER+PR+ tumors, a positive association was seen between n - 6 intake and breast cancer, and a marginally significant inverse association was observed for EPA intake.
authors.affiliation: Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Grace Y
authors.initials: GY
authors.lastname: Kiyabu
authors.affiliation: AXA Department of Health and Human Security, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.|Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Manami
authors.initials: M
authors.lastname: Inoue
authors.affiliation: AXA Department of Health and Human Security, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.|Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Eiko
authors.initials: E
authors.lastname: Saito
authors.affiliation: AXA Department of Health and Human Security, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Sarah K
authors.initials: SK
authors.lastname: Abe
authors.affiliation: Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Norie
authors.initials: N
authors.lastname: Sawada
authors.affiliation: Department of Nutrition Management, Sagami Women's University, Kanagawa Prefecture, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Ishihara
authors.affiliation: Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Motoki
authors.initials: M
authors.lastname: Iwasaki
authors.affiliation: Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Taiki
authors.initials: T
authors.lastname: Yamaji
authors.affiliation: Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Taichi
authors.initials: T
authors.lastname: Shimazu
authors.affiliation: Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Shizuka
authors.initials: S
authors.lastname: Sasazuki
authors.affiliation: Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Shibuya
authors.affiliation: Epidemiology and Prevention Group, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Tsugane
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000517:prevention & control*; D004032:Diet; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage*; D005260:Female; D005399:Fishes; D006801:Humans; D015994:Incidence; D007564:Japan; D008460:Meat; D011446:Prospective Studies; D065840:Protective Factors; D012307:Risk Factors
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6
keywords: breast cancer; diet; fatty acids; fish; receptor