Fenugreek is one of those plants that sits in an interesting space between food and medicine. You might have encountered it as a spice in Indian curry without realising it. The seeds have a distinctive bitter, slightly sweet flavour that works surprisingly well in spice blends. But fenugreek has also been used medicinally for centuries, particularly for supporting lactation in breastfeeding mothers and managing blood sugar in people with diabetes.

The question, as always with traditional remedies: does it actually work? I’ve gone through the clinical research to find out.

What is fenugreek?

Fenugreek (Trigonella foenum-graecum) is an annual plant belonging to the legume family. It’s native to the Mediterranean region, southern Europe, and western Asia, though it’s now cultivated widely, particularly in India, which produces most of the world’s supply.

The plant grows to about 60 centimetres tall and produces small white flowers that develop into long, narrow pods containing the golden-brown seeds. These seeds are the part used both as a spice and as a supplement.

In cooking, fenugreek appears in several forms. The dried seeds are used whole or ground in curry powders and spice blends. The leaves (called methi in Hindi) are used fresh or dried as a herb. You’ll also find fenugreek in some pickles and chutneys.

The seeds contain an unusual mix of compounds: soluble fibre (galactomannan), saponins (particularly diosgenin), flavonoids, and alkaloids including trigonelline. They’re also a source of vitamin A, thiamine, riboflavin, vitamin C, and niacin. The high fibre content is probably relevant to some of its effects on blood sugar and cholesterol.

What are the proven benefits of fenugreek?

1. Blood sugar regulation

This is probably the best-supported use of fenugreek. The research here is actually reasonably consistent.

A meta-analysis published in 2016 pooled data from 12 randomised controlled trials involving 1,173 patients with diabetes or prediabetes [1]. The results showed that fenugreek significantly reduced fasting blood glucose, two-hour postprandial blood glucose, and glycosylated haemoglobin (HbA1c) compared to controls. Total cholesterol also dropped.

The proposed mechanisms make biological sense. The high soluble fibre content (about 50% of the seed by weight) slows carbohydrate absorption in the gut. The compound 4-hydroxyisoleucine, found almost exclusively in fenugreek, appears to stimulate insulin secretion in a glucose-dependent manner, meaning it doesn’t cause hypoglycaemia when blood sugar is already normal [2].

My honest assessment: the effect sizes aren’t dramatic, but they’re real. Fenugreek isn’t going to replace diabetes medication, but it might be a useful addition to dietary management. The catch is that many studies used quite high doses (up to 100 grams of defatted seed powder daily), which is impractical for most people.

2. Testosterone levels

This one gets a lot of attention online, particularly in fitness communities. The claim is that fenugreek can boost testosterone levels in men.

A 2020 meta-analysis examined four randomised controlled trials with 206 male participants [3]. The pooled results did show that fenugreek extract was associated with higher total testosterone levels compared to placebo.

The mechanism is thought to involve diosgenin, a saponin that acts as a precursor to steroid hormones. There’s also speculation that fenugreek might inhibit aromatase (the enzyme that converts testosterone to oestrogen) or 5-alpha reductase (which converts testosterone to dihydrotestosterone).

Here’s where I’d urge caution: the sample sizes in these studies are small, and the testosterone increases, while statistically significant, were modest. We’re not talking about anything close to the effects of testosterone replacement therapy. If you’re expecting fenugreek to produce noticeable physical changes, you’ll probably be disappointed. It might help a little at the margins, particularly for men with borderline-low testosterone, but it’s not a substitute for medical treatment if there’s a genuine deficiency.

3. Lactation support

Fenugreek has been used as a galactagogue (milk-producing agent) for centuries. It’s probably the most common herbal remedy recommended to breastfeeding mothers struggling with milk supply.

A 2017 meta-analysis examined five randomised controlled trials comparing fenugreek (as capsules or tea) to placebo or control groups [4]. The overall analysis did show that fenugreek increased milk production compared to placebo.

However, and this is important, the effect was far inferior to some other galactagogues tested, including Coleus amboinicus leaf and date palm. The quality of the studies was also variable.

My take: fenugreek probably does help somewhat with milk production, but the effect appears modest. If you’re struggling with low milk supply, it might be worth trying, but manage your expectations. It’s not a magic solution. And given that fenugreek can transfer through breast milk and give the baby a maple syrup-like odour (more on that later), it’s worth discussing with a healthcare provider first.

4. Blood lipid regulation

High cholesterol affects a substantial proportion of adults in developed countries, and dyslipidaemia is a major risk factor for cardiovascular disease. Can fenugreek help?

A 2020 systematic review and meta-analysis examined 12 randomised controlled trials involving 560 participants [5]. The results showed that fenugreek seed products significantly reduced total cholesterol, triglycerides, and LDL cholesterol while raising HDL cholesterol.

The mechanism likely relates to the high soluble fibre content, which can bind bile acids in the gut and increase their excretion. This forces the liver to use more cholesterol to make new bile acids, reducing circulating cholesterol levels.

Honest assessment: the effects are real but not huge. If you have significantly elevated cholesterol and cardiovascular risk, you’re probably going to need medication. But as part of dietary management, fenugreek might contribute to modest improvements. It’s not going to replace statins.

5. Primary dysmenorrhoea

Primary dysmenorrhoea refers to painful menstruation without any underlying pelvic pathology. It’s extremely common, affecting somewhere between 45% and 95% of women of reproductive age, depending on which study you read.

A randomised, double-blind, placebo-controlled trial from 2014 tested fenugreek seed powder in 101 women with moderate to severe dysmenorrhoea [6]. The fenugreek group reported significantly less pain than the placebo group. They also reported fewer systemic symptoms like fatigue, headache, nausea, and vomiting.

This is just one study, and it was fairly small. The mechanism isn’t entirely clear, though it might relate to fenugreek’s anti-inflammatory properties or possible effects on prostaglandin synthesis.

I wouldn’t call this evidence definitive, but it’s promising enough that fenugreek might be worth trying for women who experience painful periods and want to avoid or supplement NSAIDs. It’s cheap and appears safe in the doses studied.

Side effects of fenugreek

Fenugreek is generally well tolerated in healthy adults at typical supplement doses. However, several side effects have been reported:

Gastrointestinal effects are the most common complaint. These include diarrhoea, stomach upset, bloating, and increased flatulence. The high fibre content is likely responsible. Starting with a lower dose and increasing gradually may help.

Maple syrup odour is a distinctive and unusual effect. Fenugreek contains sotolone, a compound also found in maple syrup. When you consume enough fenugreek, this compound appears in your sweat and urine, creating a maple syrup smell. It’s harmless but can be alarming if you’re not expecting it. In breastfeeding mothers, it can also transfer to the baby.

Other reported effects include dizziness and headache, though these are less common.

Safety precautions (9 contraindications)

Who should avoid fenugreek

1. Pregnant women. This is the most important contraindication. Fenugreek has been shown to cause uterine contractions in animal studies and may increase the risk of premature labour or birth defects at high doses. It has traditional use as an inducer of labour, which tells you something about its uterine effects. Do not use during pregnancy.

2. Children. There’s insufficient safety data for fenugreek use in children. Until proper studies are done, it should be avoided.

3. People with legume allergies. Fenugreek is a legume. If you have allergies to peanuts, soybeans, chickpeas, or green beans, you may also react to fenugreek. Symptoms can include nasal congestion, coughing, wheezing, facial swelling, and in severe cases, anaphylaxis.

4. People with thyroid conditions. Animal studies have found that fenugreek seed extract may be associated with hypothyroidism [7]. If you have a thyroid condition or take thyroid medication, discuss fenugreek with your doctor before using it.

5. People with hormone-sensitive conditions. Fenugreek seeds contain compounds that may have oestrogen-like effects [8]. This means people with conditions that can be worsened by oestrogen should avoid it. This includes breast cancer, uterine fibroids, endometriosis, ovarian cancer, and uterine cancer. Men with a history of prostate cancer should also be cautious.

Drug interactions

6. Diabetes medications. Since fenugreek can lower blood sugar, combining it with diabetes medications may cause hypoglycaemia. Medications in this category include glimepiride, glyburide (glibenclamide), glipizide, tolbutamide, insulin, pioglitazone, rosiglitazone, and chlorpropamide. If you have diabetes and want to try fenugreek, work with your doctor to monitor blood sugar carefully.

7. Blood thinners and anticoagulants. Fenugreek may have mild anticoagulant effects. Combining it with blood thinners could theoretically increase bleeding risk. Relevant medications include warfarin, heparin, enoxaparin, dalteparin, aspirin, clopidogrel, ibuprofen, naproxen, and diclofenac.

8. About to give birth. Even in late pregnancy, fenugreek should be avoided just before delivery because it may cause the newborn to have a maple syrup-like body odour. This can be confused with maple syrup urine disease, a serious metabolic disorder, potentially leading to unnecessary medical investigation of the infant.

Other considerations

9. History of pulmonary embolism. There has been one case report of a man who developed pulmonary embolism while taking a testosterone booster containing fenugreek [9]. The causal relationship is unclear, but if you have a history of blood clots, mention this to your doctor before using fenugreek.

References

Gong J, Fang K, Dong H, et al. Effect of fenugreek on hyperglycaemia and hyperlipidemia in diabetes and prediabetes: A meta-analysis. J Ethnopharmacol. 2016;194:260-268. PubMed
Sauvaire Y, Petit P, Broca C, et al. 4-Hydroxyisoleucine: a novel amino acid potentiator of insulin secretion. Diabetes. 1998;47(2):206-210. PubMed
Mansoori A, Hosseini S, Zilaee M, Hormoznejad R, Fathi M. Effect of fenugreek extract supplement on testosterone levels in male: A meta-analysis of clinical trials. Phytother Res. 2020;34(7):1550-1555. PubMed
Khan TM, Wu DB, Dolzhenko AV. Effectiveness of fenugreek as a galactagogue: A network meta-analysis. Phytother Res. 2018;32(3):402-412. PubMed
Askarpour M, Hadi A, Miraghajani M, Symonds ME, Sheikhi A, Ghaedi E. Beneficial effects of fenugreek glycoside supplementation in overweight/obese patients with type 2 diabetes mellitus: A systematic review and meta-analysis. Diabetes Metab Syndr Obes. 2020;13:667-679. PubMed
Younesy S, Amiraliakbari S, Esmaeili S, Alavimajd H, Nouraei S. Effects of fenugreek seed on the severity and systemic symptoms of dysmenorrhea. J Reprod Infertil. 2014;15(1):41-48. PubMed
Tahiliani P, Kar A. Role of Moringa oleifera leaf extract in the regulation of thyroid hormone status in adult male and female rats. Pharmacol Res. 2000;41(3):319-323. PubMed
Sreeja S, Anju VS, Sreeja S. In vitro estrogenic activities of fenugreek Trigonella foenum graecum seeds. Indian J Med Res. 2010;131:814-819. PubMed
Qureshi A, Naughton DP, Petroczi A. A systematic review on the herbal extract Tribulus terrestris and the roots of its putative aphrodisiac and performance enhancing effect. J Diet Suppl. 2014;11(1):64-79. PMC