Isoflavones decrease insomnia in postmenopause

Author: Hachul H, Brandao LC, D’Almeida V, Bittencourt LR, Baracat EC, Tufik S
Publication: Menopause. 2010 Aug 19

Women during menopause often experience insomna, which is the inability to fall asleep or stay asleep at night. This insomnia is caused by symptoms of menopause, such as hot flashes, hormonal changes and mood swings.

The intake of isoflavones by menopausal women could reduce sleep problems, according to Dr. Helena Hachul of the Sao Paolo Federal University. She and her colleagues investigate whether the intake of isoflavones might be beneficial. They randomly divided 38 postmenopausal women with insomnia in two group, the first took daily 80 mg isoflavones and the second a placebo for four months. All women had to complete a questionnaire and underwent polysomnography, which involved spending the night in a sleep lab to monitor the sleep quality.

The polysomnography showed that women who took isoflavones increased their sleep efficiency by about 8%, whereas those for the placebo group increased it only by 5%. Before the study 90% of women in the isoflavone group showed sleeping problems, but after four months this figure dropped to 37%. The women also reported less sleep problems, as was confirmed by an objective sleep study. In the placebo group, the percentage of women with sleep problems fell from 95 to 63%.

The researchers could not confirm the exact mechanism by which isoflavones alleviate insomnia. Because of the small scale of this study they recommended more studies to confirm their results.