Soy Food Consumption and Risk of Prostate Cancer: A Meta-Analysis of Observational Studies
- 3 September 2009
- journal article
- research article
- Published by Taylor & Francis Ltd in Nutrition and Cancer
- Vol. 61 (5), 598-606
- https://doi.org/10.1080/01635580902825639
Abstract
Soybean products have been suggested to have a chemo preventive effect against prostate cancer. The aim of this study was to provide a comprehensive meta-analysis on the extent of the possible association between soy-based food consumption and the risk of prostate cancer. Five cohort studies and 8 case-control studies were identified using MEDLINE, EMBASE, CINAHL, Korea Medical Database, KoreaMed, Korean studies Information Service System, Japana Centra Revuo Medicina, China National Knowledge Infrastructure, and a manual search. Summary odds ratios (ORs) comparing high versus low categories of soybean consumptions were calculated on the basis of the random effect model. We analyzed the associations based on the different types of soybean consumptions. The summary ORs (95% CI) for total soy foods were 0.69 (CI = 0.57–0.84) and 0.75 (CI = 0.62–0.89) for nonfermented soy foods. Among individual soy foods, only tofu yielded a significant value of 0.73 (CI = 0.57–0.92). Consumption of soybean milk, miso, or natto did not significantly reduce the risk of prostate cancer. Genistein and daidzein were associated with a lower risk of prostate cancer. This systematic review suggests that soy food consumption could lower the risk of prostate cancer. This conclusion, however, should be interpreted with caution because various biases can affect the results of a meta-analysis.Keywords
This publication has 30 references indexed in Scilit:
- A prospective study of diet and prostate cancer in Japanese menCancer Causes & Control, 2004
- Measuring inconsistency in meta-analysesBMJ, 2003
- Quantifying heterogeneity in a meta-analysisStatistics in Medicine, 2002
- Risk factors for prostate carcinoma in TaiwanCancer, 1999
- Phytoestrogen intake and prostate cancer: A case‐control study using a new databaseNutrition and Cancer, 1999
- Development of a database for assessing dietary phytoestrogen intakeNutrition and Cancer, 1999
- A comparison of prospective and retrospective assessments of diet in a study of colorectal cancerNutrition and Cancer, 1998
- Meta-analysis in clinical trialsControlled Clinical Trials, 1986
- The file drawer problem and tolerance for null results.Psychological Bulletin, 1979