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Evidence matters

Isoflavone supps

enhance mood in



Q Does an isoflavone supplement enhance mood or cognition in healthy postmenopausal women?


The study was a double-blind crossover trial that included 78 healthy postmenopausal women within 20 per cent of normal

weight range and no recent use of hormone therapy. Women with major depression or recent use of psychoactive medications were excluded.

Women were randomised to six months of daily treatment with an easily absorbable phytoestrogen compound containing 60mg isoflavones (40-45 per cent genistein, 40-45 per cent daidzein, and 10-20 per cent glycitein) or placebo.

Multiple measures of cognitive performance and mood were administered at the end of each treatment period.

Mean scores on the instruments to measure mood were in the normal range at the end of each treatment period with small differences favouring the women taking iso-flavones (five of the differences were statistically significant, albeit without correcting for multiple comparisons).

Eight mood characteristics — sad, confused, fearful, irritable, tense, angry, tired and agitated — were also measured on 100-point visual analog scales.

Results at the end of treatment favored phytoestrogens on all but the agitated


Mean scores on eight tests of cognition were in the normal range without any statistically significant differences.

Among the women completing the study, 49 stated that they preferred phytoestrogen, nine preferred placebo, and 16 did not state a preference.

Level of evidence

1b Randomised controlled trial (double-blinded) (see html)

Bottom line

Isoflavone treatment enhanced mood in healthy postmenopausal women, but did not improve scores on cognitive measures. The overall risks and benefits of long-term treatment remain


This Patient Oriented Evidence that Matters (POEM) is taken from InfoPOEMS/Inforetriever, a point of care evidence-based medicine tool, published by John Wiley. For more information, e-mail: or visit

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