Postmenopausal breast cancer is associated with high intakes of Omega-6 fatty acids (Sweden) Elisabet Wirfält Malmö Diet and Cancer Study, Department of Medicine, Surgery and Orthopedics, Lund University, Sweden; Malmö Diet and Cancer Study, UMAS, entrance 59 SMI, SE-205 02 Malmö, Sweden. Ph.: +46 40 33 35 18; Fax: +46 40 33 62 15; Email: elisabet.wirfalt@smi.mas.lu.se Irene Mattisson Malmö Diet and Cancer Study, Department of Medicine, Surgery and Orthopedics, Lund University, Sweden Bo Gullberg Malmö Diet and Cancer Study, Department of Community Medicine, Lund University, Sweden Ulla Johansson Malmö Diet and Cancer Study, Department of Medicine, Surgery and Orthopedics, Lund University, Sweden Håkan Olsson Malmö Diet and Cancer Study, Department of Oncology, Lund University, Sweden Göran Berglund Malmö Diet and Cancer Study, Department of Medicine, Surgery and Orthopedics, Lund University, Sweden Abstract Objective: To estimate the postmenopausal breast cancer risk associated with total fat intake, different types and relative proportions of dietary fat using a nested, matched case–control study within the Malmö Diet and Cancer (MDC) cohort, Sweden. Methods: Among women 50 years or older at baseline (n = 12,803), incident breast cancer cases (n = 237) were matched to controls (n = 673) on age and screening date. Data were obtained by a “novel” diet history method, a structured questionnaire, and anthropometric measurements. Conditional logistic regression examined breast cancer risks associated with quintiles of fat intake residuals adjusted for energy and potential confounders. Results: Saturated fat and the Omega-3–Omega-6 fatty acid ratio were not related to increased risks, but positive trends were seen for total (p = 0.031), monounsaturated (p = 0.002), and polyunsaturated fat (p = 0.0009), especially Omega-6 fatty acids and the polyunsaturated–saturated fat ratio (p = 0.004). With mutual adjustment for different types of fat, an elevated risk remained significant in the highest Omega-6 fatty acid quintile (RR = 2.08, 95% CI 1.08–4.01). Conclusions: Postmenopausal breast cancer was positively associated with total, monounsaturated, and polyunsaturated fat. However, with mutual adjustment for other types of fat, specifically high intakes of Omega-6 fatty acids were associated with an increased risk. Cancer Causes and Control 13 (10): 883-893, December 2002 Ann's NOTE: Be careful, farm-raised fish is high in Omega-6 NOT Omega-3. Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.