Daidzein-metabolizing phenotypes in relation to bone density and body composition among premenopausal women in the United States.

BACKGROUND

Bone density has been suggested as a marker of cumulative hormone exposure. Small studies also suggest that patterns of daidzein metabolism may be related to hormone concentrations. To our knowledge, no studies in premenopausal women have compared bone density by daidzein-metabolizing phenotypes in the absence of a soy intervention.

OBJECTIVE

The objective was to evaluate the relationship between daidzein-metabolizing phenotypes [equol and O-desmethylangolensin (ODMA) production] and bone density and body composition in premenopausal women in the United States.

MATERIALS/METHODS: Two hundred and three women attended a clinic visit during which their bone density and body composition were measured by DXA, and 200 (99 %) provided a urine sample following a 3-day soy challenge. Samples were analyzed for isoflavones to determine daidzein-metabolizing phenotypes.

RESULTS

In adjusted analyses, there were no differences in hip, spine, femoral neck, or head bone mineral density (BMD) or body composition between producers and non-producers of either equol or ODMA (P > .05).

CONCLUSIONS

In this population of low-soy consuming premenopausal women, there were no associations between daidzein-metabolizing phenotypes and hip, spine, femoral neck, or head BMD or body composition, suggesting that these phenotypes per se do not influence premenopausal bone density or body composition.