Abstract
Background
Epidemiologic studies have reported conflicting findings between soy- and legume-derived
dietary isoflavones and risk of endometrial cancer.
Objective
The aim of the present meta-analysis was to quantitatively investigate the association
between daily intake of soy- and legume-derived isoflavones and risk of endometrial
cancer.
Design
A broad search was conducted in the following electronic databases: PubMed, EMBASE,
Google Scholar, the Cochrane Library, the China Knowledge Resource Integrated Database,
and the Chinese Biomedical Database based on combinations of the key words endometrial cancer, isoflavone, soy, and legume for epidemiologic studies that focused on relationships between dietary isoflavones
and endometrial cancer risk. A fixed-effect or random-effect model was used to pool
study-specific risk estimates.
Results
A total of 13 epidemiologic studies were included in the present meta-analysis, consisting
of three prospective cohort studies and 10 population-based case-control studies.
The final results indicated that higher dietary isoflavone levels from soy products
and legumes were associated with a reduced risk of endometrial cancer (odds ratio
[OR] 0.81, 95% CI 0.74 to 0.89). Low heterogeneous bias was observed (I2=11.7%; P=0.327). Subgroup analyses were conducted based on study design, source of dietary
isoflavones, and study region. When restricted to study design, dietary isoflavones
from soy and legumes played a role in prevention of endometrial cancer in case-control
studies (OR 0.81, 95% CI 0.73 to 0.90). However, there did not appear to be an association
between dietary isoflavones and endometrial cancer in cohort studies (OR 0.81, 95%
CI 0.66 to 1.00). Significant associations were found between dietary isoflavones
from soy products (OR 0.82, 95% CI 0.72 to 0.92) and legumes (OR 0.84, 95% CI 0.74
to 0.96) and endometrial cancer. Dietary isoflavones were associated with reduced
incidence of endometrial cancer, both in Asian countries (OR 0.78, 95% CI 0.66 to
0.93) and non-Asian countries (OR 0.82, 95% CI 0.73 to 0.92).
Conclusions
The findings suggest a weak inverse association between higher consumption of dietary
isoflavones from soy products and legumes and endometrial cancer risk. However, there
is still a need for large, prospective epidemiologic studies that provide a higher
level of evidence to verify these findings.
Keywords
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Biography
X. Zhong is a public health physician, Department of Epidemiology, School of Public Health and Tropical Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, Southern Medical University, Guangzhou, China.
Biography
J. Ge is a master's degree candidate, Department of Epidemiology, School of Public Health and Tropical Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, Southern Medical University, Guangzhou, China.
Biography
S. Chen is a public health physician, Department of Epidemiology, School of Public Health and Tropical Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, Southern Medical University, Guangzhou, China.
Biography
Y. Xiong is a doctoral degree candidate, Department of Epidemiology, School of Public Health and Tropical Medicine, Guangdong Provincial Key Laboratory of Tropical Disease Research, Southern Medical University, Guangzhou, China.
Biography
S.-J. Ma is a doctoral degree candidate, School of Public Health, Central South University, Changsha, Hunan, China.
Biography
Q. Chen is a professor of epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, China.
Article info
Publication history
Published online: December 01, 2016
Accepted:
September 28,
2016
Received:
January 28,
2016
Footnotes
STATEMENT OF POTENTIAL CONFLICT OF INTEREST No potential conflict of interest was reported by the authors.
FUNDING/SUPPORT None to report.
Identification
Copyright
© 2018 by the Academy of Nutrition and Dietetics.
