Red clover
Reviews disagree on hot flashes. Several found about 1 to 2 fewer a day than placebo, while a Cochrane review and two US trials found no difference, with placebo alone cutting them by up to 63%. Two reviews found lower total cholesterol. Bone results were mixed. Side effects matched placebo in trials of up to 3 years.
Add to Bio HackChecked 2026-11-13
- Status
- Dietary supplement in the US. Not approved by FDA for any use, and like other supplements not reviewed by FDA before sale [1].
- Also called
- Trifolium pratense, red clover isoflavones, red clover extract, Promensil, Rimostil, biochanin A, formononetin, cow clover, meadow clover, wild clover
- Taken for
- hot flashes, night sweats, menopause symptoms, natural estrogen, bone density, osteoporosis, cholesterol, heart health, vaginal dryness, overactive bladder, mood and sleep during menopause, breast health
Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on
Shown to help2
- ModerateShown to lower total cholesterol by about 11 to 12 mg/dL in menopausal women in pooled trials. Reviews disagreed on LDL, HDL and triglycerides.
- LimitedLimited evidence: one review found less vaginal dryness and better vaginal cell maturation with 80 mg a day of red clover than in control groups.
Reported risks0
No risks sourced yet.
What people take it for, and what was found
Shown to help2
Cholesterol and blood fats
Shown to lower total cholesterol by about 11 to 12 mg/dL in menopausal women in pooled trials. Reviews disagreed on LDL, HDL and triglycerides.
Compared with placebo [11][12]
The numbers and sources
- Effect
- A 2020 review of 10 trials found total cholesterol fell 11.21 mg/dL more than placebo (0.29 mmol/L, 95% CI 0.06 to 0.53), while LDL (-5.02 mg/dL, 95% CI -13.53 to 3.48), triglycerides (-13.28 mg/dL, 95% CI -28.34 to 0.88) and HDL (+5.41 mg/dL, 95% CI -3.09 to 13.92) did not change significantly [11]. A 2018 review of 12 trials found total cholesterol fell 12.34 mg/dL (95% CI 6.48 to 18.21), LDL 10.61 mg/dL (95% CI 5.72 to 15.51) and triglycerides 10.18 mg/dL (95% CI 4.13 to 16.23), and HDL rose 1.60 mg/dL (95% CI 0.17 to 3.03) [12].
- Population
- 910 perimenopausal and postmenopausal women in 10 trials [11]. 1,284 perimenopausal and postmenopausal women in 12 trials lasting 4 weeks to 18 months [12].
- Sources
- [11], [12]
- Caveats
- Heterogeneity was very high (I² 88% to 98%) [11]. The two reviews overlap in the trials they include.
Vaginal dryness
Limited evidence: one review found less vaginal dryness and better vaginal cell maturation with 80 mg a day of red clover than in control groups.
Compared with control groups the abstract does not describe [10]
The numbers and sources
Mixed results2
Hot flashes
Mixed results: several reviews found about 1 to 2 fewer hot flashes a day than placebo, while a Cochrane review and two US trials found no difference.
Compared with placebo [2][3][4][5][6][7][8][9]; control groups the abstract does not describe [10]; conjugated estrogens with medroxyprogesterone [9]
The numbers and sources
- Effect
- A Cochrane review pooled 5 trials of the extract Promensil and found no difference from placebo in daily hot flashes (MD -0.93, 95% CI -1.95 to 0.10). Across 43 phytoestrogen trials, placebo alone cut hot flashes by 1% to 59% [2]. A 2021 review of 8 trials found 1.73 fewer a day than placebo (95% CI 0.18 to 3.28), with larger effects in women with 5 or more a day and at 80 mg or more [3]. A 2026 review of 9 trials found a small to moderate reduction (SMD -0.446, 95% CI -0.807 to -0.084) [4]. A 2014 review found 1.34 fewer a day at 3 to 4 months (95% CI 0.77 to 1.90) but no difference at 12 months (MD 0.89, 95% CI -0.07 to 1.85) [5]. Earlier reviews found a borderline reduction of 1.5 a day (95% CI -2.94 to 0.03) [6] and a nonsignificant 1.99 (95% CI -4.12 to 0.14) [10]. A review limited to Promensil 80 mg found 3.63 fewer a day (95% CI 2.70 to 4.56) in 3 trials [7]. In a 12-week US trial, from 8.1 hot flashes a day, counts fell 5.1 on Promensil, 5.4 on Rimostil and 5.0 on placebo [8]. In a 12-month US trial, vasomotor symptoms fell 57% on red clover, 63% on placebo and 94% on hormone therapy, and only hormone therapy differed from placebo [9].
- Population
- 43 trials with 4,364 women, 5 of them pooled for Promensil [2]. 8 trials [3]. 9 trials of women aged 40 to 65 with 2.1 to 11.7 hot flashes a day at baseline [4]. Perimenopausal and postmenopausal women in 5 trials [6], 3 trials [7] and others [5][10]. 252 women aged 45 to 60 with at least 35 hot flashes a week [8]. A four-arm 12-month trial, with 89 women in the hormone therapy arm [9].
- Sources
- [2], [3], [4], [5], [6], [10], [7], [8], [9]
- Caveats
- Placebo responses were large: 5.0 fewer hot flashes a day in one trial [8] and a 63% drop in another [9]. Heterogeneity was high (I² 87% [3], 95% [10]). The Promensil-only review used a fixed-effect model and found results differed between crossover and parallel designs [7]. Many trials were small and at high risk of bias [2].
Bone density
Mixed results: three small trials found less spine bone loss than placebo over 12 weeks to a year, while a 3-year trial found no difference in bone density.
Compared with placebo [13][14][15]; placebo, with calcium, magnesium and calcitriol in both groups [16]
The numbers and sources
- Effect
- Over a year, loss of lumbar spine bone density was smaller on a red clover isoflavone tablet than placebo (P 0.03), with no difference at the hip [13]. Over 12 weeks, lumbar spine density fell only in the placebo group [14]. Over a year in women with low bone density, a red clover extract with probiotics limited loss at the lumbar spine (-0.99% against -2.2%), femoral neck (-1.04% against -3.05%) and trochanter (-0.67% against -2.79%) [16]. Over 3 years, bone density did not differ between red clover and placebo [15].
- Population
- 205 women aged 49 to 65 [13]. 60 menopausal women [14]. 78 postmenopausal women with osteopenia [16]. 401 women aged 35 to 70 with a family history of breast cancer [15].
- Sources
- [13], [14], [16], [15]
- Caveats
- Small trials of different extracts, one combined with probiotics [16]. Bone density is not fracture, and no trial measured fractures.
Not shown to help2
Mood, sleep and sex during menopause
Limited evidence: trials and one review found no clear improvement in mood, sleep, sexual problems or quality of life over placebo in menopausal women.
Compared with placebo [8][9]; control groups the abstract does not describe [10]
The numbers and sources
- Effect
- A 2016 review found red clover had less effect on psychological symptoms, sexual problems and sleep [10]. Quality of life improved similarly on two red clover extracts and placebo over 12 weeks [8]. Over 12 months, there were in general no improvements in other menopause symptoms [9].
- Population
- Women in pooled trials [10]. 252 women [8]. A four-arm 12-month trial [9].
- Sources
- [10], [8], [9]
- Caveats
- Secondary outcomes in hot flash trials.
Overactive bladder
One small trial found fermented red clover did not relieve overactive bladder symptoms more than placebo in postmenopausal women over 3 months.
Compared with placebo [17]
The numbers and sources
Doses studied
Hot flash trials gave 37.1 to 160 mg of red clover isoflavones a day for 12 weeks to 12 months [4]. The 12-week US trial used Promensil at 82 mg and Rimostil at 57 mg of total isoflavones a day [8]. Reviews found larger hot flash effects at 80 mg a day or more [3][7]. Bone trials used a tablet with 26 mg biochanin A, 16 mg formononetin, 1 mg genistein and 0.5 mg daidzein for a year [13], 37.1 mg a day in a drink for 12 weeks [14], and 60 mg of isoflavone aglycones with probiotics for a year [16]. The 3-year trial used 40 mg a day [15].
Risks
Checked, no increase found3
Side effects in trials
Not shown to raise side effects over placebo in trials of red clover isoflavones lasting up to 3 years in women.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- Adverse events were comparable on two red clover extracts and placebo over 12 weeks [8]. A standardized extract showed no safety concerns over 12 months [9]. Over 3 years, the adverse event profile was similar to placebo [15]. A Cochrane review found no adverse effects of phytoestrogens for up to 2 years [2].
- Population
- 252 women [8]. A 12-month trial [9]. 401 women [15]. 43 trials [2].
- Sources
- [8], [9], [15], [2]
- Caveats
- Trials were not powered to find rare harms.
Uterine lining and hormone levels
Not shown to thicken the uterine lining in trials up to 3 years. FSH and LH did not change, and results on estradiol were borderline.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- A Cochrane review found no estrogen-like stimulation of the endometrium or vagina for up to 2 years [2]. Endometrial thickness did not differ from placebo over 3 years [15] or in a review (SMD 0.022, 95% CI -0.380 to 0.424) [18]. In a small trial, an endometrial growth marker did not change [19]. Estradiol, FSH and LH did not change against placebo over a year [20], and FSH did not differ over 3 years [15]. A review found nonsignificant changes in FSH, LH, SHBG and testosterone, and a rise in estradiol (SMD 0.240, 95% CI -0.001 to 0.482, P 0.051) that its authors called significant [18].
- Population
- 43 trials [2]. 401 women [15]. 11 trials [18]. 30 perimenopausal women aged 45 to 50 [19]. 205 women aged 49 to 65 [20].
- Sources
- [2], [15], [18], [19], [20]
- Caveats
- The review's estradiol interval crossed zero [18].
Breast density and breast cancer
Not shown to raise breast density over 1 to 3 years in two trials, including women with a family history of breast cancer. Evidence on breast cancer itself is limited.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- Over a year, mammographic breast density fell in both groups, with no significant difference between red clover and placebo [20]. Over 3 years in women with a family history of breast cancer, breast density did not differ from placebo [15]. A systematic review found the evidence on red clover limited, with existing studies suggesting no breast cancer-promoting effect [21].
- Population
- 205 women aged 49 to 65 [20]. 401 women aged 35 to 70 with a first-degree relative with breast cancer [15]. 131 studies of soy and red clover [21].
- Sources
- [20], [15], [21]
- Caveats
- Breast density is a marker, not cancer. No trial measured breast cancer as an outcome.
Possible, not studied in people1
Pregnancy and breastfeeding
Not studied in people. Red clover isoflavones are structurally similar to estrogen, and NCCIH flags pregnancy and breastfeeding as a safety concern for the supplements.
No study in people. This rests on how it acts in the body.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- NCCIH describes red clover's isoflavones as structurally similar to estrogen and flags use during pregnancy or breastfeeding as a possible safety concern [1].
- Population
- No studies in pregnant or breastfeeding women were found [1].
- Sources
- [1]
- Caveats
- A government summary, not a study.
Claims tested and not found
- That red clover reduces hot flashes over a year. A 12-month trial found no difference from placebo [9], and a review found none at 12 months [5].
- That red clover lowers breast density. Density fell in both groups over a year, with no significant difference [20].
- That red clover relieves overactive bladder. Most symptom measures did not improve against placebo [17].
- That red clover improves other menopause symptoms. A 12-month trial found in general no improvements [9].
Related
Sources
- National Center for Complementary and Integrative Health. Red Clover. https://www.nccih.nih.gov/health/red-clover
- Lethaby A, Marjoribanks J, Kronenberg F, et al. Phytoestrogens for menopausal vasomotor symptoms. Cochrane Database of Systematic Reviews. 2013. https://doi.org/10.1002/14651858.CD001395.pub4
- Kanadys W, Barańska A, Błaszczuk A, et al. Evaluation of Clinical Meaningfulness of Red Clover (Trifolium pratense L.) Extract to Relieve Hot Flushes and Menopausal Symptoms in Peri- and Post-Menopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. 2021. https://doi.org/10.3390/nu13041258
- Jiang W, Wu K. The effectiveness of red clover on hot-flash in menopausal women: a GRADE-assessed systematic review and meta-analysis. European Journal of Obstetrics & Gynecology and Reproductive Biology. 2026. https://doi.org/10.1016/j.ejogrb.2026.115226
- Gartoulla P, Han MM. Red clover extract for alleviating hot flushes in postmenopausal women: a meta-analysis. Maturitas. 2014. https://doi.org/10.1016/j.maturitas.2014.06.018
- Thompson Coon J, Pittler MH, Ernst E. Trifolium pratense isoflavones in the treatment of menopausal hot flushes: a systematic review and meta-analysis. Phytomedicine. 2007. https://doi.org/10.1016/j.phymed.2006.12.009
- Myers SP, Vigar V. Effects of a standardised extract of Trifolium pratense (Promensil) at a dosage of 80mg in the treatment of menopausal hot flushes: A systematic review and meta-analysis. Phytomedicine. 2017. https://doi.org/10.1016/j.phymed.2016.12.003
- Tice JA, Ettinger B, Ensrud K, et al. Phytoestrogen supplements for the treatment of hot flashes: the Isoflavone Clover Extract (ICE) Study: a randomized controlled trial. JAMA. 2003. https://doi.org/10.1001/jama.290.2.207
- Geller SE, Shulman LP, van Breemen RB, et al. Safety and efficacy of black cohosh and red clover for the management of vasomotor symptoms: a randomized controlled trial. Menopause. 2009. https://doi.org/10.1097/gme.0b013e3181ace49b
- Ghazanfarpour M, Sadeghi R, Roudsari RL, et al. Red clover for treatment of hot flashes and menopausal symptoms: A systematic review and meta-analysis. Journal of Obstetrics and Gynaecology. 2016. https://doi.org/10.3109/01443615.2015.1049249
- Kanadys W, Baranska A, Jedrych M, et al. Effects of red clover (Trifolium pratense) isoflavones on the lipid profile of perimenopausal and postmenopausal women: A systematic review and meta-analysis. Maturitas. 2020. https://doi.org/10.1016/j.maturitas.2019.11.001
- Luís Â, Domingues F, Pereira L. Effects of red clover on perimenopausal and postmenopausal women's blood lipid profile: A meta-analysis. Climacteric. 2018. https://doi.org/10.1080/13697137.2018.1501673
- Atkinson C, Compston JE, Day NE, et al. The effects of phytoestrogen isoflavones on bone density in women: a double-blind, randomized, placebo-controlled trial. American Journal of Clinical Nutrition. 2004. https://doi.org/10.1093/ajcn/79.2.326
- Thorup AC, Lambert MN, Kahr HS, et al. Intake of Novel Red Clover Supplementation for 12 Weeks Improves Bone Status in Healthy Menopausal Women. Evidence-Based Complementary and Alternative Medicine. 2015. https://doi.org/10.1155/2015/689138
- Powles TJ, Howell A, Evans DG, et al. Red clover isoflavones are safe and well tolerated in women with a family history of breast cancer. Menopause International. 2008. https://doi.org/10.1258/mi.2007.007033
- Lambert MNT, Thybo CB, Lykkeboe S, et al. Combined bioavailable isoflavones and probiotics improve bone status and estrogen metabolism in postmenopausal osteopenic women: a randomized controlled trial. American Journal of Clinical Nutrition. 2017. https://doi.org/10.3945/ajcn.117.153353
- Villadsen AB, Holm-Jacobsen JN, Prabhala BK, et al. Use of Fermented Red Clover Isoflavones in the Treatment of Overactive Bladder in Postmenopausal Women: A Randomized, Double-Blinded, Placebo-Controlled Trial. Nutrients. 2023. https://doi.org/10.3390/nu15194165
- Ghazanfarpour M, Sadeghi R, Latifnejad Roudsari R, et al. Effects of red clover on hot flash and circulating hormone concentrations in menopausal women: a systematic review and meta-analysis. Avicenna Journal of Phytomedicine. 2015. https://pmc.ncbi.nlm.nih.gov/articles/PMC4678495/
- Hale GE, Hughes CL, Robboy SJ, et al. A double-blind randomized study on the effects of red clover isoflavones on the endometrium. Menopause. 2001. https://doi.org/10.1097/00042192-200109000-00008
- Atkinson C, Warren RM, Sala E, et al. Red-clover-derived isoflavones and mammographic breast density: a double-blind, randomized, placebo-controlled trial. Breast Cancer Research. 2004. https://doi.org/10.1186/bcr773
- Fritz H, Seely D, Flower G, et al. Soy, red clover, and isoflavones and breast cancer: a systematic review. PLoS One. 2013. https://doi.org/10.1371/journal.pone.0081968