Soy Consumption and Phytoestrogens: Effect on Serum Prostate Specific Antigen When Blood Lipids and Oxidized Low-Density Lipoprotein are Reduced in Hyperlipidemic Men

No AccessJournal of UrologyCLINICAL UROLOGY: Original Articles1 Feb 2003Soy Consumption and Phytoestrogens: Effect on Serum Prostate Specific Antigen When Blood Lipids and Oxidized Low-Density Lipoprotein are Reduced in Hyperlipidemic Men DAVID J.A. JENKINS, CYRIL W.C. KENDALL, MARIO A. D'COSTA, CHUNG-JA JACKSON, EDWARD VIDGEN, WILLIAM SINGER, JASON A. SILVERMAN, GEORGE KOUMBRIDIS, JOHN HONEY, A. VENKET RAO, NEIL FLESHNER, and LAURENCE KLOTZ DAVID J.A. JENKINSDAVID J.A. JENKINS , CYRIL W.C. KENDALLCYRIL W.C. KENDALL , MARIO A. D'COSTAMARIO A. D'COSTA , CHUNG-JA JACKSONCHUNG-JA JACKSON , EDWARD VIDGENEDWARD VIDGEN , WILLIAM SINGERWILLIAM SINGER , JASON A. SILVERMANJASON A. SILVERMAN , GEORGE KOUMBRIDISGEORGE KOUMBRIDIS , JOHN HONEYJOHN HONEY , A. VENKET RAOA. VENKET RAO , NEIL FLESHNERNEIL FLESHNER , and LAURENCE KLOTZLAURENCE KLOTZ View All Author Informationhttps://doi.org/10.1016/S0022-5347(05)63944-4AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: Herbal remedies high in phytoestrogens have been shown to reduce serum prostate specific antigen (PSA) and have been proposed as a treatment for prostate cancer. Soy proteins used to lower serum cholesterol are rich sources of phytoestrogens. Therefore, we assessed the effect of soy consumption on serum PSA in men who had participated in cholesterol lowering studies. Materials and Methods: For 3 to 4 weeks 46 healthy middle-aged men with a range of starting PSA values took soy (mean 44 gm. soy protein daily, 116 mg. isoflavones daily) or control foods, and a subgroup of men took a lower level of soy supplements for 3 months. PSA was measured at the start and end of each treatment. Results: Soy had no significant effect on serum total or free PSA, independent of PSA starting value or isoflavone intake. The lack of effect on PSA was seen, although soy intake was sufficient to reduce low-density lipoprotein cholesterol (5.8 ± 2.2%, p = 0.012), the estimated coronary heart disease risk (6.1 ± 2.8% for 10 years, p = 0.032) and the serum concentration of oxidized low-density lipoprotein measured as conjugated dienes (9.5 ± 3.4%, p = 0.008) in the 3 to 4-week study. In addition, the lack of effect of soy on PSA persisted for the 3 months of the extended study. Conclusions: At levels of soy intake which reduce low-density lipoprotein cholesterol any potential benefits of soy consumption on prostate cancer are likely to occur for reasons other than alterations in hormone activity. References 1 : Endocrine disrupters and human health. BMJ2001; 323: 1317. Google Scholar 2 : Soy intake and cancer risk: a review of the in vitro and in vivo data. Nutr Cancer1994; 21: 113. 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Google Scholar From the Clinical Nutrition and Risk Factor Modification Center and Department of Medicine, Divisions of Endocrinology and Metabolism, and Urology, St. Michael's Hospital, Division of Urology, University Health Network Sunnybrook & Women's College Health Sciences Centre, St. Joseph's Health Centre, Departments of Nutritional Sciences, Medicine and Surgery, Faculty of Medicine, University of Toronto, Toronto, and Laboratory Services Division, University of Guelph, Guelph, Ontario, Canada© 2003 by American Urological Association, Inc.FiguresReferencesRelatedDetails Volume 169 Issue 2 February 2003 Page: 507-511 Advertisement Copyright & Permissions© 2003 by American Urological Association, Inc.Keywordsprostateneoplasms, hormone-dependentandrogens, phytotherapyisoflavonesMetrics Author Information DAVID J.A. JENKINS Requests for reprints: Clinical Nutrition and Risk Factor Modification Center, St. Michael's Hospital, 61 Queen St. East, Toronto, Ontario, Canada M5C 2T2. More articles by this author CYRIL W.C. KENDALL More articles by this author MARIO A. D'COSTA More articles by this author CHUNG-JA JACKSON More articles by this author EDWARD VIDGEN More articles by this author WILLIAM SINGER More articles by this author JASON A. SILVERMAN More articles by this author GEORGE KOUMBRIDIS More articles by this author JOHN HONEY More articles by this author A. VENKET RAO More articles by this author NEIL FLESHNER Financial interest and/or other relationship with Astra-Zeneca, Aventis, Bio.-Advantex Pharma and Protein Technologies. More articles by this author LAURENCE KLOTZ More articles by this author Expand All Advertisement PDF downloadLoading ...