title: Dietary carbohydrates, fiber, and breast cancer risk.
abstract: Dietary fiber, fiber fractions, carbohydrate, glycemic index, and glycemic load were prospectively assessed five times over 18 years with a validated food frequency questionnaire in relation to breast cancer risk among 88,678 women (aged 34-59 years at baseline) in the Nurses' Health Study. Incident breast cancer occurred in 4,092 of these women between 1980 and 1998. The authors observed no material association between carbohydrate intake, glycemic index and glycemic load, total dietary fiber intake, and breast cancer risk. The relative risks for the highest versus the lowest quintile of intake were 0.97 (95% confidence interval (CI): 0.87, 1.08) for carbohydrates, 1.08 (95% CI: 0.97, 1.19) for glycemic index, 0.99 (95% CI: 0.89, 1.10) for glycemic load, and 0.98 (95% CI: 0.87, 1.11) for fiber. The relative risk comparing those in the highest 0.7% of fiber intake (>30 g/day) with those in the lowest 10% of fiber intake (< or =10 g/day) was 0.68 (95% CI: 0.43, 1.06). Analyses stratified by menopausal status and body mass index also showed no clear risk pattern. In this cohort of middle-aged women, no overall association was found for dietary carbohydrates, glycemic index and glycemic load, and breast cancer risk. This study also confirmed the lack of an overall association between intake of fiber and fiber types and breast cancer risk observed in other prospective studies.
authors.affiliation: Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. michelle.holmes@channing.harvard.edu
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Holmes
authors.forename: Simin
authors.initials: S
authors.lastname: Liu
authors.forename: Susan E
authors.initials: SE
authors.lastname: Hankinson
authors.forename: Graham A
authors.initials: GA
authors.lastname: Colditz
authors.forename: David J
authors.initials: DJ
authors.lastname: Hunter
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000453:epidemiology / Q000209:etiology*; D004040:Dietary Carbohydrates; D004043:Dietary Fiber; D005260:Female; D038321:Glycemic Index; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009726:Nurses; D009749:Nutrition Surveys; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
chemical_list: D004040:Dietary Carbohydrates; D004043:Dietary Fiber