Review
Effects of isoflavones and amino acid therapies for hot flashes and co-occurring symptoms during the menopausal transition and early postmenopause: A systematic review
- Annette J. Thomasa, , ,
- Rita Ismailb,
- Lisa Taylor-Swansona,
- Lori Crayc,
- Janet G. Schnalld,
- Ellen Sullivan Mitchelle,
- Nancy Fugate Woodsf
Abstract
Aims
Review
controlled clinical trials of isoflavones and amino acid preparation
effects on hot flashes and at least one other symptom including mood,
sleep, pain, and cognitive function that women report during the
menopausal transition and early postmenopause.
Methods
An
experienced reference librarian searched PubMed/Medline, CINAHL Plus,
PsycInfo, Cochrane Database of Systematic Reviews, Cochrane Central
Register of Controlled Trials, Web of Science, EMBASE, AMED, and
Alt-Health Watch for English-language randomized controlled trials
between 2004 and July 2011. Seventeen trials of isoflavones and amino
acid effects on hot flashes and one additional symptom were identified.
Results
In
five trials of soy isoflavone preparations, two (6 g soy germ extract
and 25 g soy protein in soy nuts) significantly decreased hot flashes,
but no other symptoms. In the seven trials of other isoflavones, six
significantly reduced hot flashes; in addition, red clover (80 mg)
significantly reduced mood symptoms; Rexflavone (350 mg) for women with
Kupperman Index > 20 significantly reduced sleep symptoms; two trials
had significant reductions for pain: isoflavone powder (90 mg) and red
clover (80 mg). The only trial in this systematic review that
significantly reduced cognitive symptoms was red clover (80 mg). In one
trial, red clover isoflavone (80 mg/day) significantly relieved hot
flashes, mood, pain, and cognitive symptoms. Amino acids yielded no
significant results. Equol supplements of 30 mg/day for non-Equol
producing women significantly reduced mood symptoms in one trial. The
magnolia bark extract combination significantly reduced hot flashes,
mood, and sleep symptoms.
Conclusions
Isoflavone
trials yielded significant reductions on hot flashes and co-occurring
symptoms during the menopausal transition and postmenopause, but studies
require replication with larger sample sizes and attention to
measurement of outcomes.
Keywords
- Menopausal transition;
- Soy;
- Isoflavones;
- Amino acids;
- Hot flashes;
- Symptom clusters
Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.