title: Consumption of whole grains and cereal fiber in relation to cancer risk: a systematic review of longitudinal studies.
abstract: Evidence from previous reviews is supportive of the hypothesis that whole grains may protect against various cancers. However, the reviews did not report risk estimates for both whole grains and cereal fiber and only case-control studies were evaluated. It is unclear whether longitudinal studies support this conclusion.
  
  
  
  To evaluate associations between whole grains and cereal fiber in relation to risk of lifestyle-related cancers data from longitudinal studies was evaluated.
  
  
  
  The following 3 databases were systematically searched: PubMed, EMBASE, and Cochrane CENTRAL.
  
  
  
  A total of 43 longitudinal studies conducted in Europe and North America that reported multivariable-adjusted risk estimates for whole grains (n = 14), cereal fiber (n = 23), or both (n = 6) in relation to lifestyle-related cancers were included.
  
  
  
  Information on study location, cohort name, follow-up duration, sample characteristics, dietary assessment method, risk estimates, and confounders was extracted.
  
  
  
  Of 20 studies examining whole grains and cancer, 6 studies reported a statistically significant 6%-47% reduction in risk, but 14 studies showed no association. Of 29 studies examining cereal fiber intake in relation to cancer, 8 showed a statistically significant 6%-49% reduction in risk, whereas 21 studies reported no association.
  
  
  
  This systematic review concludes that most studies were suggestive of a null association. Whole grains and cereal fiber may protect against gastrointestinal cancers, but these findings require confirmation in additional studies.
authors.affiliation: N. Makarem is with the Department of Nutrition, Food Studies and Public Health, New York University, New York, New York, USA. J.M. Nicholson is with the Department of Medical Library, New York University School of Medicine, New York, New York, USA. E.V. Bandera is with the Rutgers School of Public Health, Rutgers-The State University of New Jersey, and the Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA. N.M. McKeown is with the Jean Mayer USDA Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, USA. N. Parekh is with the College of Global Public Health, Department of Nutrition, Food Studies and Public Health, and Department of Population Health, New York University, New York, New York, USA.
authors.forename: Nour
authors.initials: N
authors.lastname: Makarem
authors.affiliation: N. Makarem is with the Department of Nutrition, Food Studies and Public Health, New York University, New York, New York, USA. J.M. Nicholson is with the Department of Medical Library, New York University School of Medicine, New York, New York, USA. E.V. Bandera is with the Rutgers School of Public Health, Rutgers-The State University of New Jersey, and the Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA. N.M. McKeown is with the Jean Mayer USDA Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, USA. N. Parekh is with the College of Global Public Health, Department of Nutrition, Food Studies and Public Health, and Department of Population Health, New York University, New York, New York, USA.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Nicholson
authors.affiliation: N. Makarem is with the Department of Nutrition, Food Studies and Public Health, New York University, New York, New York, USA. J.M. Nicholson is with the Department of Medical Library, New York University School of Medicine, New York, New York, USA. E.V. Bandera is with the Rutgers School of Public Health, Rutgers-The State University of New Jersey, and the Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA. N.M. McKeown is with the Jean Mayer USDA Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, USA. N. Parekh is with the College of Global Public Health, Department of Nutrition, Food Studies and Public Health, and Department of Population Health, New York University, New York, New York, USA.
authors.forename: Elisa V
authors.initials: EV
authors.lastname: Bandera
authors.affiliation: N. Makarem is with the Department of Nutrition, Food Studies and Public Health, New York University, New York, New York, USA. J.M. Nicholson is with the Department of Medical Library, New York University School of Medicine, New York, New York, USA. E.V. Bandera is with the Rutgers School of Public Health, Rutgers-The State University of New Jersey, and the Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA. N.M. McKeown is with the Jean Mayer USDA Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, USA. N. Parekh is with the College of Global Public Health, Department of Nutrition, Food Studies and Public Health, and Department of Population Health, New York University, New York, New York, USA.
authors.forename: Nicola M
authors.initials: NM
authors.lastname: McKeown
authors.affiliation: N. Makarem is with the Department of Nutrition, Food Studies and Public Health, New York University, New York, New York, USA. J.M. Nicholson is with the Department of Medical Library, New York University School of Medicine, New York, New York, USA. E.V. Bandera is with the Rutgers School of Public Health, Rutgers-The State University of New Jersey, and the Rutgers Cancer Institute of New Jersey, New Brunswick, New Jersey, USA. N.M. McKeown is with the Jean Mayer USDA Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy, Tufts University, Boston, Massachusetts, USA. N. Parekh is with the College of Global Public Health, Department of Nutrition, Food Studies and Public Health, and Department of Population Health, New York University, New York, New York, USA niyati.parekh@nyu.edu.
authors.forename: Niyati
authors.initials: N
authors.lastname: Parekh
mesh_terms: D004032:Diet; D004043:Dietary Fiber; D002523:Edible Grain; D005060:Europe / Q000453:epidemiology; D006801:Humans; D008137:Longitudinal Studies; D009369:Neoplasms / Q000453:epidemiology*; D009656:North America / Q000453:epidemiology; D012306:Risk
keywords: cancer risk; cereal fiber; longitudinal studies; systematic review; whole grains.