The effects of bioavailable red clover isoflavones for menopausal symptoms and associated diseases

Background: Due to their estrogenic capabilities isoflavones have been shown to have beneficial effects on the symptoms of menopause and associated diseases.

Aim: We tested the effects of a highly bioavailable and aglycone rich isoflavones derived from Red Clover (RC) on existing menopausal symptoms and associated diseases.

Methods: A total of 60 post-menopausal women with existing symptoms of menopause (> 5 hot flushes/day), mean age of 52.5 and mean follicle stimulating hormone of 72.4 were randomly assigned either a twice daily dose of RC extract (33.7 mg/d of isoflavone aglycones) or placebo formula for 12 weeks. The primary endpoint was change in hot flush frequency (HFF) and hot flush intensity (HFI) from baseline, as measured by 24 hour skin conductance (SC) on the arm at the ante brachia at weeks 0, 6 and 12. Bone mineral density (BMD) was assessed by DEXA at weeks 0 and 12.

Results: No significant (NS) change was found within the placebo group in either HFF or HFI. A significant reduction in HFI (p = 0.0302) from baseline was found within the RC group, equating to a mean of – 32.1%. There was also significant decrease in HFF within the RC treated group (p = 0.0168) equating to a mean of – 15.4%. An expected significant fall in BMD occurred within the placebo group at the hip (µ0.85 SE 0.02 – µ0.84 SE 0.019) and the spine (p = 0.0013; µ1.046 SE 0.025 – µ1.031 SEM 0.026) regions, the RC group also had a significant decrease in hip BMD (p = 0.038; µ0.913 SE 0.024 – µ0.905 SE 0.02). There was NS change from baseline (µ1.057, SE 0.00429) to week 12 (µ 1.057, SE 0.00426) in BMD at spinal region within the RC group.

Conclusion: Highly bioavailable RC derived isoflavones can reduce physiological symptoms of the menopause and can attenuate estrogen dependent bone mineral resorption associated with menopause. Isoflavones present a compelling low risk alternative to hormone replacement therapy. SCs are a useful tool for capturing objective physiological data for menopause symptoms.

Keywords: Phytoestrogen, isoflavone, osteopenia, menopause, skin conductance

References:

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