Abstract
Objectives:
To investigate the effect on hot flushes of a soy isoflavone extract alone (Study
A) and with the addition of a supplement of polyunsaturated fatty acids, PUFAs (Study
B).
Methods:
Subjects were postmenopausal women (29 in Study A, 28 in Study B) with more than five
troublesome hot flushes per day. Both studies were double-blind randomized placebo-controlled
trials with cross-over design, of 24-week duration. After a 2-week observation period,
they were randomized to receive two capsules per day providing 60 mg of isoflavones or placebo for 12 weeks; thereafter, women who had taken isoflavones
were given placebo for a second 12-week period, and vice-versa. Women in the Study
B were given also two capsules per day containing a PUFA supplement for the entire
24-week test period.
Results:
Both studies showed the isoflavone extract to have no greater efficacy on hot flushes
than the placebo. During the 24 weeks of the Study B there was a progressive and highly
significant reduction in the number of hot flushes, independent of whether the women
had begun with isoflavones or with placebo.
Conclusion:
In these two trials the isoflavone extract did not show greater efficacy on the hot
flushes than the placebo. The reduction of hot flushes observed in the Study B might
be due to the PUFA supplement. PUFAs, particularly Omega (Ω) 3-fatty acids, could
reduce hot flushes through their influence on neuronal membranes and/or the modulation
of the neurotransmitter function and the serotoninergic system. Studies specifically
designed to document the action of PUFAs on hot flushes would be welcome.
Keywords
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to MaturitasAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Dietary flour supplementation decreases post-menopausal hot flushes: effect of soy and wheat.Maturitas. 1995; 21: 189-195
- The effect of dietary soy supplementation on hot flushes.Obstet Gynecol. 1998; 91: 6-11
- Effect of soy protein supplementation on serum lipoproteins, blood pressure and menopausal symptoms in perimenopausal women.Menopause. 1999; 6: 7-13
- Randomised placebo-controlled trial of isoflavone supplement and menopausal symptoms in women.Climacteric. 1999; 2: 85-92
- Evaluation of soy phytoestrogens for the treatment of hot flashes in breast cancer survivors: a North Central Cancer Treatment Group Trial.J Clin Oncol. 2000; 18: 1068-1074
- The effects of soy protein containing phytoestrogens on menopausal symptoms in postmenopausal women.Climacteric. 2000; 3: 161-167
- Modulation of learning, pain thresholds and thermoregulation in the rat by preparations of free purified linolenic and linoleic acids: determination of the optimal Ω3 to Ω6 ratio.Proc Natl Acad Sci U S A. 1993; 90: 10345-10349
- The role of polyunsaturated fatty acids in restoring the aging neuronal membrane.Neurobiol Aging. 2002; 23: 843-853
- A cholesterol and sucrose rich diet promotes lipoprotein peroxidation and impairs insulin sensitivity in rats.Food Biochem. 2003; 27: 19-33
- Clinical effects of a standardised soy extract in postmenopausal women: a pilot study.Menopause. 2000; 7: 105-111
- Vasomotor symptom relief by soy isoflavone extract tablets in postmenopausal women: a multicenter, double-blind, randomised, placebo-controlled study.Menopause. 2000; 7: 236-242
- Isoflavones from red clover (Promensil) significantly reduce menopausal hot flush symptoms compared with placebo.Maturitas. 2002; 42: 187-193
- Isoflavone-rich or isoflavone-poor soy protein does not reduce menopausal symptoms during 24 weeks of treatment.Menopause. 2001; 8: 17-26
- Effect of soy-derived isoflavones on hot flushes, endometrial thickness and pulsatility index of the uterine and cerebral arteries.Fertil Steril. 2003; 79: 1112-1117
- Phytoestrogen supplements for the treatment of hot flashes: the isoflavone clover extract (ICE) study.JAMA. 2003; 290: 207-214
- The nature and utility of the phytoestrogens: a review of the evidence.Maturitas. 2002; 42: 173-185
- Omega-6/Omega-3 ratio and brain-related functions.World Rev Nutr Diet. 2003; 92: 37-56
- Polyunsaturated fatty acids and cerebral function: focus on monoaminergic neurotransmission.Lipids. 2001; 36: 937-944
- The role of serotonin in hot flushes.Maturitas. 2000; 36: 155-164
- Relationship between climacteric symptoms and serum serotonin levels in postmenopausal women.Climacteric. 2003; 6: 53-57
- Neurobehavior aspects of omega-3 fatty acids: possible mechanisms and therapeutic value in major depression.Alter Med Rev. 2003; 8: 410-425
- Polyunsaturated fatty acids in depression.Acta Neuropsychiatr. 2003; 15: 15-21
- The role of omega-3 fatty acids in the secondary prevention of cardiovascolar disease.Q J Med. 2003; 96: 465-480
- Polyunsaturated fatty acids. Is there a role in postmenopausal osteoporosis prevention?.Maturitas. 2002; 42: 13-22
Article info
Publication history
Accepted:
November 11,
2004
Received in revised form:
November 3,
2004
Received:
July 5,
2004
Identification
Copyright
© 2004 Published by Elsevier Inc.
