Mothers With Thyroid Issues Should be Cautious in Using Fenugreek

Natural supplements and herbs are often said to be safe and preferable during pregnancy and lactation simply for being natural. For example, fenugreek is one of the most popular supplements used to increase milk supply, and while some studies show promising results, women taking thyroid medication should avoid it or carefully monitor their thyroid levels if they choose to use it. 

As we’ve written about before (Do Supplements Really Work To Increase Milk Supply?), there are many supplements promoted to breastfeeding mothers to boost their milk supply with varied results. Fenugreek has been used for many years to promote wellness, increase milk supply and help with inflammation (particularly arthritis and urethritis). It’s a member of the pea family, sometimes used in artificial maple flavoring and a common ingredient in Indian and Chinese cooking.

A meta-analysis (which is a study that looks at all of the studies together to draw a conclusion) showed that it was better than placebos and can help increase a woman’s milk supply within as little as 24-72 hours. There are many different ways to take it: teas, capsules, liquid, seeds and powders. The recommended dose of fenugreek is 2-3 capsules (580-610 mg per capsule) 3-4 times per day, and you can stop using it once your milk supply has gone up.

It’s not clear exactly how fenugreek works, but some have proposed that it increases sweating and the breast is essentially a large sweat gland. Others have suggested that it increases certain naturally occuring hormones that stimulate milk production.

Fenugreek is listed as generally recognized as safe (GRAS) by the Food and Drug Administration. 

While there is little published research on the side effects of fenugreek, some general side effects that have been reported include nausea, headaches, vomiting, increased gas and gastrointestinal motility with loose stools. Some women have reported increased breast congestion and a maple-like taste to breast milk. As with all dietary supplements, it’s important for mothers to know the side effects and to monitor themselves and their infants. They should discuss what they’re taking with their primary care providers and lactation consultants.

That’s especially important for women who take thyroid medication. Some women who have trouble conceiving are given thyroid medication if their doctors detect hypothyroidism (an underactive thyroid gland) and it’s continued during pregnancy. Many women with normal thyroid levels and no difficulties with conception develop thyroid abnormalities during pregnancy and are placed on levothyroxine (or equivalent) medication. 

While there isn’t much published research on the efficacy and safety of taking fenugreek for women with thyroid conditions, animal studies have shown that fenugreek lowers blood T3 levels when given to mice and rats and also creates hypoglycemic effects (low blood sugar). 

Based on data from animal studies, it’s recommended to be careful when taking fenugreek or even avoiding it altogether if you’re struggling with thyroid levels after pregnancy and during lactation. I would also recommend that if someone is taking fenugreek regularly, even if they have never been found to have had a thyroid problem, that they have their thyroid functions tested just to be safe.

Fenugreek is listed as generally recognized as safe (GRAS) by the FDA and as long as mothers are aware of the possible side effects, this is a good option to try to increase supply. However, mothers with thyroid conditions should be careful and consult with their physician before taking it. 

If you are concerned about your milk supply, you can find more information here or download the Emily’s Care app and connect with our virtual lactation consultant. 


  1. Panda S, Tahiliani P., Kar A, Inhibition of Triiodothyronine Production by Fenugreek Seed Extract in Mice and Rats. Pharmacological Research, Vol 40., no 5, 1999

  2. Tahiliani P., Kar A., The Combined Effects of Trigonella and Allium Extracts in the Regulation of Hyperthyroidism in Rats. Phytomedicine 10:665-68, 2003

  3. Tahiliani P., Kar A., Mitigation of Thyroxine-Induced Hyperglycemia by Two Plant Extracts. Phytotherapy Research 17, 294-96, 2003

  4. El-Wakf A., Hassan H., Mahmoud A., Habza M. Fenugreek Potent Activity Against Nitrate-Induced Diabetes in Young Rats and Adult Male Rtas. Cytotechnology 67:437-47, 2015.


1 comment

  • The title on this page is in white font and the background is white with a photo making the title at the heading illegible to my almost 50 yr old eyes. A fatter font and a light pastel background could be an improvement.


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