Dietary Fiber Intake in Young Adults and Breast Cancer Risk

Pediatrics. 2016 Mar;137(3):e20151226. doi: 10.1542/peds.2015-1226. Epub 2016 Feb 1.

Abstract

Objective: We evaluated fiber intake during adolescence and early adulthood in relation to breast cancer (BC) risk in the Nurses' Health Study II.

Methods: Among 90,534 premenopausal women who completed a dietary questionnaire in 1991, we documented 2833 invasive BC cases during 20 years of follow-up. In 1998, 44,263 of these women also completed a questionnaire about their diet during high school; among these women, we documented 1118 cases of BC by end of follow-up. Multivariable-adjusted Cox proportional hazards regression was used to model relative risks (RRs) and 95% confidence intervals (CIs) for BC across categories of dietary fiber.

Results: Among all women, early adulthood total dietary fiber intake was associated with significantly lower BC risk (RR for highest versus lowest quintile 0.81; 95% CI 0.72-0.91; Ptrend = .002). Higher intakes of soluble fiber (RR for highest versus lowest quintile 0.86; 95% CI 0.77-0.97; Ptrend = .02) and insoluble fiber (RR for highest versus lowest quintile 0.80; 95% CI 0.71-0.90; Ptrend < .001) were each associated with lower BC risk. Total dietary fiber intake in adolescence was also associated with lower BC risk (RR for highest versus lowest quintile 0.84; 95% CI 0.70-1.01; Ptrend = .04). For the average of fiber intake during adolescence and early adult life, the RR comparing highest with lowest quintiles was 0.75 (95% CI 0.62-0.91, Ptrend = .004).

Conclusions: Our findings support the hypothesis that higher fiber intakes reduce BC risk and suggest that intake during adolescence and early adulthood may be particularly important.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Breast Neoplasms / epidemiology*
  • Dietary Fiber / administration & dosage*
  • Female
  • Humans
  • Incidence
  • Longitudinal Studies
  • Middle Aged
  • Nurses
  • Postmenopause
  • Premenopause
  • Prospective Studies
  • Risk Factors
  • Surveys and Questionnaires
  • United States / epidemiology
  • Young Adult