Long used in the Indian Ayurvedic medical tradition, fenugreek has been employed in the treatment of a very wide variety of conditions affecting almost every system of the body on top of its widespread use in the flavouring of food. The many uses of fenugreek are being realised in the western world.
Fenugreek is a plant with a huge number of traditional uses. These include general detoxification and kidney health, skin and hair, digestive problems like heartburn and stomach irritation, production of breastmilk, reduction of cholesterol levels, blood sugar control and diabetes, respiratory health, treatment of menopause symptoms, libido enhancement in men and women, and testosterone boosting.
It is fenugreek's ability to boost testosterone levels that has generated the majority of interest from manufacturers of supplements. It is also thought by many to have effects on muscle growth.
Fenugreek Side Effects Testosterone Booster
Fenugreek has a long reputation of use as a testosterone booster. The plant is known to contain hormonal precursors, which are similar to the human steroid hormone precursor DHEA, which can effect levels of both male and female sex hormones.
There is only a very small amount of scientific study into the testosterone boosting effects of fenugreek, which has concluded that the herb has very little effect on levels of sex hormones (1). nonetheless, people are physiologically different, and many men have reported side effects from fenugreek use that reflect enhanced testosterone levels. These include increased libido and sexual performance, increased muscle growth and fat loss.
Fenugreek Side Effects Men
The most common male side effects of fenugreek relate to increased testosterone levels. This plant has traditionally been used for its aphrodisiac properties, and increase in libido is amongst the most common side effects for men using fenugreek.
Some men unfortunately experience the flip side of this, and experience an increase in oestrogen levels with fenugreek supplementation. This can cause a decreased libido, impotence, and gyno (or man boobs). Thankfully, these symptoms are reversible and have been shown to disappear when supplementation is stopped.
Fenugreek Side Effects Women
Women are also prone to experiencing hormonal effects from fenugreek, and it is known to boost the female libido as well as the male. Fenugreek is known to have oestrogenic activity, and it is being investigated for a potential role as a natural hormone replacement therapy for menopause. Fenugreek is widely known as a substance that encourages the production of breast milk, and is used for this reason by many mothers. Fenugreek use during pregnancy is strongly discouraged, as it is thought to be able to induce premature labour (2).
Fenugreek Side Effects Thyroid
Fenugreek has been noted to have another hormonal effect, and when taken in high doses it has the potential to exert various changes in levels of thyroid hormones, inhibiting the conversion of thyroxine (T4) to triiodothyronine (T3), which is the active form of this hormone that stimulates the throid gland.
Reduced thyroid activity has a number of effects, including sluggish metabolism, drop in body temperature, and reduced utilisation of protein for growth. These side effects are thought to occur with sustained use at very high dosage (over 100mg fenugreek seed/kg bodyweight/day for more than two weeks) and are unlikely to occur at average therapeutic doses used (3). In spite of this, people with a predisposition to thyroid problems should consult their doctor before using fenugreek.
Fenugreek Side Effects Weight Gain
High oestrogen levels can promote the storage of excess energy as body fat, while a depressed thyroid function means a lower basal metabolic rate and less muscle growth. This is a combination of factors which has the potential to cause fat gain. This is something that will more likely be seen at higher, long term doses (3). There is a very wide variation in the way people respond to fenugreek, and as we have seen before, other people see a decrease in fat and greater muscle growth when supplementing with this product. The side effects of fenugreek typically resolve very quickly after supplementation is discontinued.
Fenugreek Side Effects Smell
Use of fenugreek has been known to cause a sweet body odour, similar to maple syrup. While this is not unpleasant, and can be easily masked with deodorants and colognes, it is quite a distinctive smell, and some people are understandably very averse to having a permanent odour. Reducing the amount of fenugreek taken may reduce or alleviate this symptom.
Fenugreek Side Effects Diabetes
The effect of Fenugreek on blood sugar is well established. The plant is currently the subject of a good deal of research looking into its hypoglycaemic properties and potential as a natural treatment for both type 1 and 2 diabetes in humans (4). Fenugreek has the strong potential to interfere with the treatment of diabetes, and should be avoided by people suffering from this condition, except under the strict supervision of a medical professional.
(1) Steels E, Rao A, Vitetta L. Physiological Aspects of Male Libido Enhanced by Standardized Trigonella foenum-graecum Extract and Mineral Formulation. Phytother Res. 2011 Feb 10.
(2) Sreeja S, Anju VS, Sreeja S. In vitro estrogenic activities of fenugreek Trigonella foenum graecum seeds. Indian J Med Res. 2010 Jun;131:814-9.
(3) Panda S, Tahiliani P, Kar A. Inhibition of triiodothyronine production by fenugreek seed extract in mice and rats. Pharmacol Res. 1999 Nov;40(5):405-9.
(4) Roberts KT. The potential of fenugreek (Trigonella foenum-graecum) as a functional food and nutraceutical and its effects on glycemia and lipidemia. J Med Food. 2011 Dec;14(12):1485-9.