Highlights
- •Red clover has gained popularity as a treatment for menopausal symptoms because it is structurally and functionally similar to 17-estradiol.
- •The results of this systematic review and meta-analysis suggest a favourable effect of red clover on lipid metabolism.
- •Taking Trifolium pratense during menopause can modify abnormal cholesterol levels.
Abstract
Aim
The aim of this systematic review and meta-analysis was to clarify the effect of a
specific standardised extract of red clover (Trifolium pratense) on the lipid profile of perimenopausal and postmenopausal women.
Methods
Medline (PubMed), EMBASE, and Cochrane Library electronic databases were searched
for papers in English reporting randomized controlled trials published up to 2017.
Reference lists from those papers were checked for further relevant publications.
Studies were identified and reviewed for their eligibility for inclusion in this review.
The changes from baseline in the levels of individual components of the lipid profiles
were used to assess differences between the active treatment and placebo groups. Weighted
mean differences and 95 % confidence intervals were calculated for continuous data
using a random-effects model.
Results
Ten eligible studies (twelve comparisons) with 910 peri- and postmenopausal women
were selected for systematic review. The meta-analysis showed changes in serum levels:
total cholesterol, −0.29 (95 % CI: −0.53 to −0.06) mmol/L [–11.21 (95 % CI: –20.49
to –13.92) mg/dL], p = 0.0136; LDL-cholesterol, −0.13 (95 % CI: −0.35 to 0.09) mmol/L
[–5.02 (95 % CI: –13.53 to 3.48) mg/dL], p = 0.2418; triglycerides, −0.15 (95 % CI:
−0.32 to 0.01) mmol/L [–13.28 (95 % CI: –28.34 to 0.88) mg/dL], p = 0.0592; and HDL-cholesterol,
0.14 (95 % CI: −0.08 to 0.36) mmol/L [5.41 (95 % CI: –3.09–13.92) mg/dL], p = 0.2103.
TheI2 statistic ranged from 87.95%–98.30 %, indicating significant heterogeneity.
Conclusions
The results suggest that a red clover extract is efficacious in reducing the concentrations
of total cholesterol; however, changes in HDL-C, LDL-C and triglycerides are not as
pronounced. Potentially, this means that women takingTrifolium pratense for menopausal symptoms can derive additional benefits from the plant’s specific
effect that corrects abnormal cholesterol levels. Additional studies are needed to
assess its effects on post-menopausal women.
Keywords
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Article info
Publication history
Published online: November 10, 2019
Accepted:
November 1,
2019
Received in revised form:
October 8,
2019
Received:
March 29,
2019
Identification
Copyright
© 2019 Elsevier B.V. All rights reserved.
