Benefits
Female sexual desire and arousal
In a double-blind, placebo-controlled trial, 80 healthy menstruating women aged 20 to 49 who reported low sexual drive took 600 mg a day or placebo for two menstrual cycles, about 8 weeks. Sexual desire and arousal improved more than with placebo. This is one trial of 80 women; its lead author also led the supplier-funded Libifem exercise trial, and no independent group has repeated it.
Hot flushes and night sweats around menopause
In a 12-week double-blind trial of 115 healthy women aged 40 to 65, 600 mg a day reduced daytime hot flushes and night sweats and improved menopause-related quality of life scores, including the sexual symptoms section, more than placebo. Estradiol levels ended up similar in both groups. The abstract names a proprietary de-husked fenugreek extract rather than Libifem by name.
Leg strength and lean mass with resistance training
In an 8-week placebo-controlled trial, women aged 25 to 45 all followed the same whole-body exercise program three times a week. The 600 mg a day group gained more leg-press strength and lean mass and lost more fat than placebo, while 300 mg a day did not change fat mass. Testosterone did not change in any group, and the supplier funded the trial.
Free testosterone and estradiol levels
In the 80-woman libido trial, 600 mg a day raised free testosterone and estradiol compared with placebo. In the later exercise trial, testosterone did not change in any group. The libido trial also measured SHBG, the protein that binds sex hormones, but its abstract reports changes only for free testosterone and estradiol, so how the extract works is not established.
Tolerability in trials
Mild digestive discomfort is the most commonly reported side effect of fenugreek in general. In the Libifem exercise trial, 7 of 129 enrolled women withdrew because of adverse events: 5 on Libifem (bloating, knee pain, acne and reflux) and 2 on placebo, including the one serious event, a bowel obstruction. Trials lasted 8 to 12 weeks, so longer-term safety is unknown.
Mechanism of action
Proposed hormone effects
The authors of the exercise trial suggest fenugreek may free more testosterone and estradiol from the proteins that carry them in the blood. The 80-woman trial did find higher free testosterone and estradiol after 600 mg a day, but this pathway has not been shown directly in people.
Possible Effects on Strength and Body Composition
The strength and body composition results in women come from one Libifem trial at 600 mg a day alongside a supervised exercise program, not from studies of other fenugreek brands in men. How the extract produces those changes has not been established.
Standardized saponin content
Libifem is standardized to 50% furostanol saponins, which helps keep batches consistent. Other fenugreek extracts use different standardizations, so results from one brand should not be assumed for another.
Clinical trials
Single-site, double-blind, randomized, placebo-controlled trial of 600 mg a day for two menstrual cycles, about 8 weeks. Hormones, sexual function questionnaires, stress, fatigue and relationship quality were measured (Rao et al. 2015, Phytotherapy Research).
80 healthy menstruating women aged 20 to 49 who reported low sexual drive.
Sexual desire and arousal improved more than with placebo, and free testosterone and estradiol rose. The abstract does not report results for stress, fatigue or relationship quality. This single trial has not been repeated by an independent group.
Randomized, placebo-controlled trial of 300 mg or 600 mg a day for 8 weeks. Everyone, including the placebo group, followed the same whole-body exercise program three times a week. Funded by Gencor Pacific (Rao et al. 2023, Frontiers in Sports and Active Living).
Women aged 25 to 45; 129 enrolled and 74 completed all requirements.
Only the 600 mg group improved leg-press strength more than placebo; it also lost about 0.96 kg of fat versus a 0.09 kg gain on placebo and gained more lean mass than the 300 mg and placebo groups. Testosterone did not change in any group. Seven women withdrew because of adverse events.
Double-blind, randomized, placebo-controlled trial of a proprietary de-husked fenugreek seed extract, 600 mg a day for 12 weeks (Steels et al. 2017, Phytotherapy Research).
115 healthy women aged 40 to 65; 104 completed.
Total menopause-specific quality of life scores improved more than placebo, including the vasomotor, psychosocial, physical and sexual sections, and daytime hot flushes and night sweats fell. Average estradiol levels were similar in both groups after treatment.