Increased Long-term Dietary Fiber Intake Is Associated With a Decreased Risk of Fecal Incontinence in Older Women

Gastroenterology. 2018 Sep;155(3):661-667.e1. doi: 10.1053/j.gastro.2018.05.021. Epub 2018 Jun 11.


Background & aims: Fiber supplements are frequently used as treatment for fecal incontinence (FI), but little is known about the role of dietary fiber in the prevention of FI.

Methods: We performed a prospective study to examine the association between long-term dietary fiber intake and risk of FI in 58,330 older women (mean age, 73 years) in the Nurses' Health Study who were free of FI in 2008. Energy-adjusted long-term dietary fiber intake was determined using food frequency questionnaires starting in 1984 and updated through 2006. We defined incident FI as at least 1 liquid or solid FI episode per month during the past year during 4 years of follow-up using self-administered biennial questionnaires. We used Cox proportional hazards models to calculate multivariable-adjusted hazard ratios and 95% CIs for FI according to fiber intake, adjusting for potential confounding factors.

Results: During 193,655 person-years of follow-up, we documented 7,056 incident cases of FI. Compared with women in the lowest quintile of fiber intake (13.5 g/day), women in the highest quintile (25 g/day) had an 18% decrease in risk of FI (multivariable hazard ratio, 0.82; 95% CI, 0.76-0.89). This decrease appeared to be greatest for risk of liquid stool FI, which was 31% lower in women with the highest intake of fiber compared with women with the lowest intake (multivariable hazard ratio, 0.69; 95% CI, 0.62-0.75). Risk of FI was not significantly associated with fiber source.

Conclusions: In an analysis of data from almost 60,000 older women in the Nurses' Health Study, we found higher long-term intake of dietary fiber was associated with decreased risk of FI. Further studies are needed to determine the mechanisms that mediate this association.

Keywords: Diarrhea; Nurses’ Health Study; Population-Based Study; Prevention.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Diet / adverse effects*
  • Diet / methods
  • Dietary Fiber / administration & dosage*
  • Dietary Fiber / analysis
  • Eating
  • Fecal Incontinence / epidemiology
  • Fecal Incontinence / etiology
  • Fecal Incontinence / prevention & control*
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Middle Aged
  • Proportional Hazards Models
  • Prospective Studies
  • Risk Factors
  • Time Factors


  • Dietary Fiber