In an invited commentary, Katherine Newton of Group Health in Seattle and Dr. Deborah Grady of the University of California San Francisco wrote that questions still remain as to whether soy may have benefits in specific groups.
For instance, they wrote, a metabolic product of daidzein known as equol is thought to be more biologically active than daidzein, but only 25 percent to 50 percent of women metabolize daidzein into equol.
Though the study found no enhanced effects for equol producers, Newton and Grady said this metabolite should have been measured immediately after daidzein ingestion in order to accurately assess equol producer status. Thus, these findings may require further investigation, they wrote.
In general, they said, efforts may need to move "away from the hope of a one-size-fits-all therapy for menopausal symptoms towards using existing treatments to target the symptoms that disturb patients most," adding that non-hormonal therapies, such as selective serotonin reuptake inhibitors and gabapentin, may be effective treatments.