[Prevalence of equol producer phenotype and its relations to lifestyle factors and dietary intakes among lifestyle factors and dietary intakes among healthy Chinese adults in Beijing].

OBJECTIVE

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 among Chinese adults in Beijing.

METHODS

100 male and 100 female adults participated in a cross-sectional study and provided twice 1d urine samples on regular diet and after 3d soy isoflavone challenge respectively. A health and demographics questionnaire, and 2d food record were completed before the urine collections. Isoflavones and their metabolites in urine were measured to determine equol phenotype by HPLC.

RESULTS

The physiological range of 24h urinary equol excretion was 0-76.56 micromol/24h, and the percentage of the equol producer phenotype was 26.8% on regular diet and 60.4% after soy isofavone challenge, respectively. There was no indication that habitual consumption of soy foods is associated with the equol producer phenotype. The correlations of isoflavone intake from 2d food record with those from urinary isoflavone levels were 0.58 for total isoflavones, 0.49 for daidzein, 0.56 for genistein, and 0.50 for glycitein (P < 0.01).

CONCLUSION

About one fourth of Chinese adults in Beijing were detected equol excretion in urine under the usually lifestyle. However, equol_producing potential was higher.