Fenugreek

What it is

Fenugreek is a plant in the pea family. Its seeds and leaves are used in cooking, especially in Indian dishes, and in traditional medicine for digestion, blood sugar and breastfeeding.

As a supplement, seed extracts are used for libido and testosterone, blood sugar support and to increase breast milk supply. Branded extracts such as Testofen are used in some male libido studies.

It is sold as a food supplement in the UK. Culinary amounts are different from concentrated doses.

How it works

Fenugreek contains saponins (such as furostanol saponins) and fibre. Saponins may influence hormone pathways, while the soluble fibre slows sugar absorption. How much of this matters at supplement doses is uncertain.

What the evidence says

• Limited Libido in men
  A few small trials with a branded extract show modest improvements in self-reported sexual function.
• Moderate Blood sugar control
  Meta-analyses of small trials suggest slight reductions in fasting glucose and HbA1c, but quality is variable.
• Limited Breast milk supply
  Small studies suggest an increase in milk volume for some mothers; results are inconsistent.
• Weak Testosterone levels
  Mixed findings, with several studies showing no meaningful rise.

Evidence ratings are our plain-English summary of how much good human research exists, not a promise of results. How we rate evidence.

Dosage and timing

• Extract doses of about 500 to 600 mg daily are common in libido studies.
• Blood sugar studies often use several grams of seed powder with meals.
• Take with food to ease digestive effects.
• If you are breastfeeding, speak to a midwife or health visitor before using. Check current guidance on dosing.

Forms and what to look for

• Standardised seed extracts (for example for saponin content) are used in libido research.
• Whole seed powder is high in fibre and cheaper.
• Teas are mild and hard to dose.
• Check the label states seed extract and the amount per capsule.

What to expect, and when

• Digestive effects may appear within days.
• Libido studies typically run for 6 to 12 weeks.
• Blood sugar effects, if any, take weeks and should be monitored if you take diabetes medicine.

Side effects

• Diarrhoea, bloating, wind and stomach upset.
• A maple syrup smell in sweat and urine, which is harmless but noticeable.
• Low blood sugar in people on glucose-lowering medicine.
• Allergic reactions, especially in people allergic to peanuts, chickpeas or other legumes.

Interactions

• Diabetes medicines: risk of low blood sugar.
• Warfarin and other anticoagulants: possible enhanced effect.
• Thyroid medication: fenugreek may interfere with absorption.
• Other oral medicines: the fibre may slow absorption, so separate doses by a couple of hours.

Who should avoid it

• Pregnant women, as fenugreek may stimulate the uterus.
• People with legume allergies.
• Anyone on anticoagulants or glucose-lowering drugs without monitoring.
• People with hormone-sensitive conditions, as a precaution.
• Anyone having surgery soon.

Risks and safety

• Concentrated doses can cause low blood sugar in people on diabetes drugs.
• Breastfed infants of mothers taking fenugreek have occasionally had reactions or a maple smell, so seek advice.
• Not WADA-prohibited, though some bodybuilding products mix ingredients, so check batches.

Buying well: quality and testing

• Choose products stating Trigonella foenum-graecum and extract type.
• Look for standardised saponin content where claimed.
• Prefer third-party tested products.
• Avoid proprietary blends with unspecified fenugreek amounts.

Bottom line

Fenugreek is a common spice with some modest evidence for blood sugar and a small signal for libido. It is not a reliable testosterone booster. People on diabetes medication, anticoagulants or who are pregnant should take advice before using supplement doses.