Soya food intake and risk of endometrial cancer among Chinese women in Shanghai: population based case-control studyBMJ 2004; 328 doi: https://doi.org/10.1136/bmj.38093.646215.AE (Published 27 May 2004) Cite this as: BMJ 2004;328:1285
- Wang Hong Xu, assistant professor1,
- Wei Zheng, professor2,
- Yong Bing Xiang, professor1,
- Zhi Xian Ruan, research staff1,
- Jia Rong Cheng, research staff1,
- Qi Dai, assistant professor2,
- Yu Tang Gao, professor1,
- Xiao Ou Shu, professor ()2
- 1Department of Epidemiology, Shanghai Cancer Institute, 2200 Xie Tu Road #25, Shanghai 200032, China
- 2Department of Medicine, Vanderbilt-Ingram Cancer Center, Vanderbilt Center for Health Services Research, Vanderbilt University, 6009 Medical Center East, 1215 21st Avenue South, Nashville, TN 37232-8300, USA
- Correspondence to: X O Shu
- Accepted 18 March 2004
Objective To evaluate the association of intake of soya food, a rich source of phytoestrogens, with the risk of endometrial cancer.
Design Population based case-control study, with detailed information on usual soya food intake over the past five years collected by face to face interview using a food frequency questionnaire.
Setting Urban Shanghai, China.
Participants 832 incident cases of endometrial cancer in women aged of 30 to 69 years diagnosed during 1997-2001 and identified from the Shanghai Cancer Registry; 846 control women frequency matched to cases on age and randomly selected from the Shanghai Residential Registry.
Main outcome measures Odds ratios for risk of endometrial cancer in women with different intakes of soya foods.
Results Regular consumption of soya foods, measured as amount of either soya protein or soya isoflavones, was inversely associated with the risk of endometrial cancer. Compared with women with the lowest quarter of intake, the adjusted odds ratio of endometrial cancer was reduced from 0.93 to 0.85 and 0.67 with increasing quarter of soya protein intake (P for trend 0.01). A similar inverse association was observed for soya isoflavones and soya fibre intake. The inverse association seemed to be more pronounced among women with high body mass index and waist:hip ratio.
Conclusion Regular intake of soya foods is associated with a reduced risk of endometrial cancer.
Contributors All authors contributed to analysis and preparation of the manuscript. ZXR directed field operations, and JRC directed the laboratory work. XOS was the principal investigator, responsible for designing and directing implementation of the overall study, and is the guarantor of this paper.
Funding This work was funded by United States Public Health Service (USPHS) grant number R01CA92585 from the National Cancer Institute.
Competing interests None declared.
Ethical approval This study was approved by the institutional review boards of Vanderbilt University and the Shanghai Cancer Institute.
- Accepted 18 March 2004