Whole Soy Supplement Reduces Muscle, Joint Pain, Menopausal Symptoms

CHICAGOA new women's health, whole-soy germ-based nutritional supplement containing Natural S-equola compound resultingwhen certain bacteria are present in the digestive tractfrom the natural metabolism, or conversion, of daidzein, an isoflavone found in whole soybeans reduced the frequency of moderate to severe hot flashes, and reduced muscle and joint pain in a study among postmenopausal U.S. women, according to peer-reviewed data presented as a poster presentation at the North American Menopause Society (NAMS) Annual Meeting. Also, the first study to report Natural S-equol contributions to bone health and a study of Natural S-equol safety were presented at NAMS.

In the double blind study of 102 U.S. postmenopausal women, eight weeks of daily SE5-OH supplement doses containing 10, 20 or 40 mg/d of Natural S-equol reduced the frequency of moderate to severe hot flashes, as did 50 mg/d of a soy isoflavone supplement. Because isoflavones are known to have mild effects on the reduction of hot flashes in menopausal women, the investigators used an isoflavone supplement as a comparator in the study.

More women in the 10, 20 and 40-mg/d Natural S-equol groups achieved a 50-percent or more reduction in their hot flash frequency than in the isoflavone group: respectively, 42.9 (P=0.056), 27.3, 25 and 16 percent.  To enroll in the study, all of the women had to experience more than 35 hot flashes per week. The 20-mg/d Natural S-equol dose neared statistical superiority (P=0.076), the 10-mg/d dose was similar (P=0.503) and the 40-mg dose was significantly more effective than the soy isoflavones in reducing hot flash frequency (P=0.021), according to a Mixed-Effect Model Repeated Measure analysis incorporating the eight weekly reports of women's hot flash frequency.

Muscle and joint pain was reduced significantly in the 10- and 20-mg/d Natural S-equol groups compared to those in the isoflavone group (P<0.05). The trial also noted treatment-emergent adverse effects in participants of all the treatment groups. Such effects occurring in more than 5 percent of each group included abdominal distention, constipation and endometrial hypertrophy, the thickening of the lining of the uterus. No trends or clinically meaningful changes were identified in laboratory blood or urine tests, electrocardiographs, physical examinations or vital signs among the participants.

The trial enrolled women aged 45 to 65 years, who had levels of follicle stimulating hormone (FSH) of 40 or more milli IU/microliter. Investigators randomized the women into four groups to receive either the isoflavone (26 women) or one of the three doses of the Natural S-equol supplement (24 in the 10 mg/d, 27 in the 20 mg/d and 25 in the 40 mg.d groups), in the form of tablets taken with breakfast and dinner meals for 12 weeks. The women had diets controlled for soy foods, isoflavone and lignans compounds.  The study included a period before the treatment weeks to allow for elimination of any women who responded to a placebo. Women also were tested to determine their ability to produce S-equol after eating soy.  The study included 70 percent equol nonproducers and 30 percent equol producers. 

Natural S-equol Inhibits Bone Break Down, Prevents Bone Mineral Density Loss

This study is the first to document evidence of SE5-OH supplements containing 10 mg/d of Natural S-equol given for 12 months significantly inhibited bone break down, or resorption, in postmenopausal women. Moreover, treatment with the 10 mg/d Natural S-equol dose significantly prevented a decrease in whole body bone mineral density (BMD), compared to placebo.

In this one-year, double blind, placebo-controlled study, investigators randomized 93 Japanese women to receive a placebo or one of three doses of SE5-OH containing Natural S-equol:  2, 6 or 10 mg/d.  Women studied were equol nonproducers, and averaged 53.8 plus or minus 3.7 years old and 2.7 plus or minus 1.2 years since menopause. After 12 months, women receiving the 10-mg/d dose of Natural S-equol had a significantly decreased, by 23.9 percent, the amount of urinary deoxypyridinoline (DPD) for 24 hours, a validated marker for bone resorption, compared to a reduction of just 2.9 percent in the placebo group (P=0.020).

In addition, the whole body BMD in the 10-mg/d group declined by 1.1 percent, significantly less than the 1.9 percent decrease of the placebo group (P=0.027) at 12 months. Serum sex and thyroid hormone concentrations did not differ among four groups at the study end.

Investigators identified no safety problems, particularly in the female reproductive system, among 101 healthy Japanese postmenopausal women who took daily SE5-OH supplement doses containing 30 mg/d Natural S-equol for 12 weeks as part of a randomized, placebo-controlled study. 

Otsuka Pharmaceutical Co. Ltd. supported all four studies. Complete reports of data from each study will be submitted for peer-review publication.