title: Prostate cancer and the influence of dietary factors and supplements: a systematic review.
abstract: BACKGROUND
  Prostate cancer is the second most common cause of cancer worldwide after lung cancer. There is increasing evidence that diet and lifestyle plays a crucial role in prostate cancer biology and tumourigenesis. Prostate cancer itself represents a good model of cancer in which to look for chemopreventive agents due to the high disease prevalence, slowly progressive nature, and long latency period. Dietary agents have gained considerable attention, often receiving much publicity in the media.
  
  
  OBJECTIVE
  To review the key evidence available for potential chemopreventive nutrients.
  
  
  METHODS
  The methodology for this review involved a PubMed search from 1990 to 2013 using the key-words "diet and prostate cancer", "nutrition and prostate cancer", "dietary factors and prostate cancer", "prostate cancer epidemiology", "prostate cancer prevention", "prostate cancer progression".
  
  
  RESULTS
  Red meat, dietary fat and milk intake should be minimised as they appear to increase the risk of prostate cancer. Fruit and vegetables and polyphenols may be preventive in prostate cancer, but further studies are needed to draw more solid conclusions and to clarify their role in patients with an established diagnosis of prostate cancer. Selenium and vitamin supplements cannot be advocated for the prevention of prostate cancer and indeed higher doses may be associated with a worse prognosis. There is no specific evidence regarding benefits of probiotics or prebiotics in prostate cancer.
  
  
  CONCLUSIONS
  From the wealth of evidence available, many recommendations can be made although more randomised control trials are required. These need to be carefully designed due to the many confounding factors and heterogeneity of the population.
authors: Centre for Gastroenterology, Royal Free Hospital, Pond Street, London NW3 2QG, UK ; Cancer Institute, University College London, Huntley Street, London, UK.
authors: Dalvinder
authors: D
authors: Mandair
authors: Centre for Gastroenterology, Royal Free Hospital, Pond Street, London NW3 2QG, UK ; Department of Pathophysiology and Organ Transplant, Universita' degli Studi di Milano and Gastroenterology Unit II, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
authors: Roberta Elisa
authors: RE
authors: Rossi
authors: Centre for Gastroenterology, Royal Free Hospital, Pond Street, London NW3 2QG, UK.
authors: Marinos
authors: M
authors: Pericleous
authors: Department of Nutrition and Dietetics, Royal Free Hospital, London, UK.
authors: Tara
authors: T
authors: Whyand
authors: Centre for Gastroenterology, Royal Free Hospital, Pond Street, London NW3 2QG, UK.
authors: Martyn Evan
authors: ME
authors: Caplin
keywords: Diet; Epidemiology; Nutrition; Prostate cancer; Tumour prevention