How we rate
“Strong” = several concordant meta-analyses or systematic reviews. “Moderate” = one synthesis, or several controlled trials. “Limited” = early trials only. The rating is about the quality of the studies, not about how useful the supplement is.
Fenugreek
A seed sold in bodybuilding for testosterone. This is precisely its least well-documented use: its best studies concern blood glucose and cholesterol.
Benefits
- Lowers fasting blood glucose, blood glucose two hours after a meal, and glycated haemoglobin in type 2 diabetes and prediabetes (10 trials, 706 participants), with no liver or kidney toxicity observed
- Improves the lipid profile — total cholesterol, LDL and triglycerides down, HDL up (15 randomised trials) — with the effect being clearest in diabetic individuals
- Acts on five components of metabolic syndrome simultaneously: fasting blood glucose, triglycerides, HDL, waist circumference and systolic blood pressure (29 randomised trials)
- Increases total testosterone in men (meta-analysis of four trials); in athletes, the meta-analysis mentions a small effect on testosterone, lean mass, fat mass, and leg press
- In 80 women reporting low libido, 600 mg per day increases free testosterone and oestradiol, and improves desire and arousal
- In 48 perimenopausal women, six weeks of supplementation reduces hot flushes, night sweats, depression and insomnia
Precautions
Medical advice is essential in cases of treated diabetes: fenugreek lowers blood glucose and its effect adds to that of the treatment. The most comprehensive meta-analysis on diabetes reveals neither hepatic nor renal toxicity. Also worth knowing: the evidence is not of the same quality depending on the use, and this is the entire point of this profile. On blood glucose and lipids, it relies on dozens of randomized trials — but the authors themselves point out uneven quality and strong heterogeneity from one study to another. On testosterone, the one sought after in the gym, the meta-analysis brings together only four trials, and the one focusing on athletes explicitly speaks of a small effect. Several of the most favorable trials involve patented extracts, and two of them are open-label, without placebo: this is the lowest level of evidence for a product sold on this precise promise. Weight and BMI, meanwhile, do not budge — a meta-analysis of twelve trials says so in black and white. Finally, on milk supply, the effect exists but remains clearly inferior to that of other herbs compared in the same analysis, and on painful periods the quality of the evidence is considered low.
Recommended dosage
Two worlds of dosages depending on the use. For blood glucose, whole seeds or powder are used at high doses: the effect on blood pressure only appears above 15 g per day. For testosterone and libido, standardised extracts are used at 400 to 600 mg per day — two different products under the same name.
How to take it
- Two products under the same name: for blood sugar and cholesterol, trials use whole seeds or seed powder; for testosterone and libido, standardized seed extracts.
- Extracts: 400 to 600 mg per day for 6 to 12 weeks in trials on testosterone and libido, in both men and women.
- Seeds: the effect on blood pressure appears starting at 15 g per day.
- For menopause: 250 mg of extract twice a day for 42 days reduced hot flashes and night sweats.
- In athletes: a small effect on testosterone, lean mass and leg press strength, only in men and with long-term supplementation.
Did you know?
Beyond its role on male testosterone, fenugreek is also effective for reducing hot flashes and improving hormonal balance in perimenopausal women.
What the studies say
This systematic review and meta-analysis explored the effect of fenugreek on the severity of dysmenorrhea in women, including four articles. The results indicated that the intensity of pain caused by primary dysmenorrhea decreased with fenugreek compared to placebo. The study highlights that the quality of evidence is low, suggesting that the true effect is uncertain and that trials with a more robust methodology are needed.
Hassanzadeh R, Shabani F, Montazeri M, Mirghafourvand M. — Current drug research reviews (2024) — View the source study
For information only: not a substitute for medical advice. Dietary supplements are not a replacement for a varied, balanced diet. Learn more