A Study of Equol Producer Phenotype and Its Relation to Dietary Intakes among 172 Healthy Chinese Adults in Shanghai

To investigate the prevalence of equol producers and the physiological range of urinary equol excretion,and also to evaluate relations between equol phenotype and lifestyle and hormone levels among Chinese adults in Shanghai,90 male and 82 female adults participated in a cross-sectional study and provided twice 24-hr urine samples on regular diet and after 3-d soy isoflavone challenge respectively.A health and demographics questionnaire and daily food frequency,and blood collections were completed before the urine collections.Soy isoflavones and their metabolites in urine were measured to determine equol phenotype by HPLC.The physiological range of 24hr urinary equol excretion was 0~33.74μmol/24hr,and the percentage of the equol producer phenotype was 30.2% on regular diet and 53.5% after 3-d soy isoflavone challenge respectively.There was no statistical difference between the equol producers and the equol non-producers about various indexes except the estradiol(P0.05).There was no statistical difference between the Eq producers and the none-producers about the frequency of food intake in this experiment(P0.05).About 1/3 of Chinese adults in Shanghai were detected equol excretion in urine under the usual lifestyle.However,equol-producing potential was higher.