title: Dietary intake of fiber, fruit and vegetables decreases the risk of incident kidney stones in women: a Women's Health Initiative report.
abstract: OBJECTIVE
  We evaluated the relationship between dietary fiber, fruit and vegetable intake, and the risk of kidney stone formation.
  
  
  METHODS
  Overall 83,922 postmenopausal women from the Women's Health Initiative observational study were included in the analysis and followed prospectively. Cox proportional hazards regression analyses were used to evaluate the associations between total dietary fiber, fruit and vegetable intake, and the risk of incident kidney stone formation, adjusting for nephrolithiasis risk factors (age, race/ethnicity, geographic region, diabetes mellitus, calcium supplementation, hormone therapy use, body mass index and calibrated caloric intake; and dietary water, sodium, animal protein and calcium intake). Women with a history of kidney stones (3,471) were analyzed separately.
  
  
  RESULTS
  Mean age of the women was 64±7 years, 85% were white and 2,937 (3.5%) experienced a kidney stone in a median followup of 8 years. In women with no history of kidney stones higher total dietary fiber (6% to 26% decreased risk, p <0.001), greater fruit intake (12% to 25% decreased risk, p <0.001) and greater vegetable intake (9% to 22% decreased risk, p=0.002) were associated with a decreased risk of incident kidney stone formation in separate adjusted models. In women with a history of stones there were no significant protective effects of fiber, fruit or vegetable intake on the risk of kidney stone recurrence.
  
  
  CONCLUSIONS
  Greater dietary intake of fiber, fruits and vegetables was associated with a reduced risk of incident kidney stones in postmenopausal women. The protective effects were independent of other known risk factors for kidney stones. In contrast, there was no reduction in risk in women with a history of stones.
authors.affiliation: Division of Urology, Department of Veterans Affairs Medical Center, and Department of Urology, Urological Research Outcomes Collaboration, University of Washington School of Medicine, Seattle, Washington. Electronic address: mathews@uw.edu.
authors.forename: Mathew D
authors.initials: MD
authors.lastname: Sorensen
authors.affiliation: Department of Urology, University of Washington School of Medicine, Seattle, Washington.
authors.forename: Ryan S
authors.initials: RS
authors.lastname: Hsi
authors.affiliation: Department of Urology, University of California, San Francisco, San Francisco, California.
authors.forename: Thomas
authors.initials: T
authors.lastname: Chi
authors.affiliation: Department of Biostatistics and Epidemiology, Georgetown University, MedStar Health Research Institute, Hyattsville, Maryland.
authors.forename: Nawar
authors.initials: N
authors.lastname: Shara
authors.affiliation: Department of Social and Preventive Medicine, University of Buffalo, Buffalo, New York.
authors.forename: Jean
authors.initials: J
authors.lastname: Wactawski-Wende
authors.affiliation: San Francisco Coordinating Center, California Pacific Medical Center Research Institute, San Francisco, California.
authors.forename: Arnold J
authors.initials: AJ
authors.lastname: Kahn
authors.affiliation: Department of Biostatistics and Epidemiology, Georgetown University, MedStar Health Research Institute, Hyattsville, Maryland.
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Preventive Medicine, Northwestern University, Chicago, Illinois.
authors.forename: Lifang
authors.initials: L
authors.lastname: Hou
authors.affiliation: Department of Urology, University of California, San Francisco, San Francisco, California.
authors.forename: Marshall L
authors.initials: ML
authors.lastname: Stoller
mesh_terms: D004032:Diet; D004043:Dietary Fiber; D005260:Female; D005638:Fruit; D006801:Humans; D007669:Kidney Calculi / Q000453:epidemiology* / Q000517:prevention & control*; D008137:Longitudinal Studies; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D018570:Risk Assessment; D014675:Vegetables; D016387:Women's Health
keywords: dietary fiber; fruit; nephrolithiasis; urinary calculi; vegetables