Beneficial effects of soybean isoflavone supplementation on bone metabolism and serum lipids in postmenopausal japanese women: a four-week study.
OBJECTIVE
The aim of this study was to determine the effects of soy isoflavones with weak estrogen-like activities both on bone metabolism and on serum lipids in perimenopausal women.


METHODS
Twenty-three healthy perimenopausal women were assigned randomly to either isoflavone or placebo groups. The isoflavone group (n = 12) received daily capsules of soy isoflavone extract (61.8 mg of isoflavones) and the placebo group (n = 11) received daily placebo capsules for four weeks. Urinary excretion of isoflavone was measured at weeks 0, 2 and 4. Urinary excretion of pyridinoline and deoxypyridinoline, bone stiffness and levels of serum cholesterol, triglyceride and cholesterol fractions were measured at weeks 0 and 4.


RESULTS
As compared to the placebo group, urinary isoflavone, primarily daidzein, excretion was increased at weeks 2 and 4 in the isoflavone group. Excretion of bone resorption markers was reduced significantly in the isoflavone group. Both total serum cholesterol and LDL cholesterol were decreased significantly in the isoflavone group. Other serum biochemical parameters were not changed in either group.


CONCLUSIONS
Soy isoflavone supplementation for four weeks showed potentially beneficial effects on bone metabolism and on serum lipids in perimenopausal women. These effects could have the potential to reduce the risks of postmenopausal osteoporosis and of cardiovascular diseases in such women.
Uesugi
Takehiko
T
Fujicco Co., Ltd., Kobe, Japan.
Fukui
Yutaka
Y
Yamori
Yukio
Y
D000596:Amino Acids / Q000652:urine; D015992:Body Mass Index; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007529:Isoflavones / Q000008:administration & dosage* / Q000652:urine; D007564:Japan; D008055:Lipids / Q000097:blood*; D010919:Placebos; D017698:Postmenopause; D013025:Glycine max / Q000737:chemistry*; D014280:Triglycerides / Q000097:blood; D014463:Ultrasonography
D000596:Amino Acids; D007529:Isoflavones; D008055:Lipids; D010919:Placebos; D014280:Triglycerides; C004742:daidzein; C015484:pyridinoline; C036020:deoxypyridinoline; D002784:Cholesterol