Comparison of 70 mg and 35 mg isoflavone soya supplement for menopause symptoms

Previous studies have reported a 20–30% reduction of climacteric symptoms with placebo, and additional reductions of 10–20% using soy preparations providing 30–104 mg/day of isoflavones [1]-[3]. However, most studies were based on data from postmenopausal women. Their hormone status was quite different when compared to women undergoing menopause transition (MT). A single center, prospective, and randomized study was conducted to investigate the effect of insoflavone supplements with different doses in climacteric symptoms in women undergoing MT. After initial screening, 48 women were recruited and assigned to two groups, 35 mg and 70 mg groups with treatment duration of 6 weeks. Isoflavone supplements were prepared from soy extract in 325 mg capsules containing 17.5 mg of isoflavones per capsule (Phyto Soya, Arkopharma Laboratories Pharmaceutique, France). Modified Greene's climacteric scale, with three additional symptoms (frequency, incontinence, and vaginal dryness), was used to assess climacteric symptoms. The clinical characteristics were similar in both groups. The results were summarized in the Table 1. Significant reduction of the scales was observed in all subgroups at the end of the study, except for vasomotor symptom in the 35 mg group, and depression in the 70 mg group. High-dose group had an earlier onset in the effect for somatic symptoms. There was no significant difference in the serum lipids profile in both groups. Most adverse effects were mild and not related to the supplement (Table 2). This study compared the effect of different doses of isoflavones on climacteric symptoms in women undergoing MT. It showed that isoflavones with a dose up to 70 mg per day was needed to significantly reduce vasomotor symptoms and to provide an earlier onset in the improvement of somatic symptoms. A low-dose group was used as the control in the present study because a placebo control group might have a higher drop out rate due to ineffectiveness. It is reasonable to assume that if the effect of high-dose regimen was superior to low-dose regimen on climacteric symptoms, the effect of high dose regimen is superior to placebo. In conclusion, the present study showed that supplement containing 70 mg of soy isoflavones may produce a modest but statistically significant reduction on the vasomotor symptoms and probably on the somatic symptoms after 12 weeks of treatment in women undergoing MT. It could therefore be used as an alternative treatment for women with contraindications for traditional hormone treatment.