title: Nutritional modifications in male infertility: a systematic review covering 2 decades.
abstract: BACKGROUND
  Studies suggest that appropriate nutritional modifications can improve the natural conception rate of infertile couples.
  
  
  OBJECTIVE
  The purpose of this study was to review the human trials that investigated the relation between nutrition and male infertility.
  
  
  METHODS
  A comprehensive systematic review of published human studies was carried out by searching scientific databases. Article selection was carried out in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The American Dietetic Association Research Design and Implementation Checklist was also used for quality assessment.
  
  
  METHODS
  A total of 502 articles were identified, of which 23 studies met the inclusion criteria.
  
  
  RESULTS
  Results indicated that a healthy diet improves at least one measure of semen quality, while diets high in lipophilic foods, soy isoflavones, and sweets lower semen quality.
  
  
  CONCLUSIONS
  The role of daily nutrient exposure and dietary quality needs to be highlighted in male infertility. Mechanistic studies addressing the responsible underlying mechanisms of action of dietary modifications are highly warranted.
  
  
  BACKGROUND
  PROSPERO 2013: CRD42013005953. Available at: http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42013005953.
authors.affiliation: L. Giahi is with the Reproductive Biotechnology Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran. S. Mohammadmoradi and A. Javidan are with the Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA. M.R. Sadeghi is with the Monoclonal Antibody Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran. l.giahi@avicenna.ac.ir.
authors.forename: Ladan
authors.initials: L
authors.lastname: Giahi
authors.affiliation: L. Giahi is with the Reproductive Biotechnology Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran. S. Mohammadmoradi and A. Javidan are with the Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA. M.R. Sadeghi is with the Monoclonal Antibody Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran.
authors.forename: Shayan
authors.initials: S
authors.lastname: Mohammadmoradi
authors.affiliation: L. Giahi is with the Reproductive Biotechnology Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran. S. Mohammadmoradi and A. Javidan are with the Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA. M.R. Sadeghi is with the Monoclonal Antibody Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran.
authors.forename: Aida
authors.initials: A
authors.lastname: Javidan
authors.affiliation: L. Giahi is with the Reproductive Biotechnology Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran. S. Mohammadmoradi and A. Javidan are with the Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA. M.R. Sadeghi is with the Monoclonal Antibody Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Sadeghi
mesh_terms: D004032:Diet; D019422:Dietary Sucrose / Q000009:adverse effects; D006801:Humans; D007248:Infertility, Male / Q000209:etiology / Q000517:prevention & control; D007529:Isoflavones / Q000009:adverse effects; D008297:Male; D009752:Nutritional Status; D055101:Semen Analysis
chemical_list: D019422:Dietary Sucrose; D007529:Isoflavones
keywords: diet; food compounds; male infertility; nutrition; sperm quality