Quick Summary
Blessed Thistle (Cnicus benedictus) is an herb traditionally used as a galactagogue to potentially support lactation. Current clinical evidence regarding its effectiveness and safety is limited and of low certainty, with no specific high-quality trials identified exclusively for Blessed Thistle. Overall, the state of evidence on herbal galactagogues, including Blessed Thistle, is inconclusive.
What is it?
Blessed Thistle, scientifically known as Cnicus benedictus, is a flowering plant native to the Mediterranean region. It has been used in traditional herbal medicine for various purposes, most notably to support breast milk production in nursing mothers.
Traditional Uses
Traditionally, Blessed Thistle has been used primarily as a galactagogue, an agent believed to help increase milk supply in breastfeeding mothers. It has also been employed historically for digestive issues and to promote appetite, although these uses are less well documented.
Active Compounds
The active compounds attributed to Blessed Thistle include bitter sesquiterpene lactones such as cnicin, along with flavonoids and polyphenolic compounds. These components are thought to contribute to its pharmacological effects, although detailed mechanisms remain unclear.
Potential Benefits with Evidence Levels
- Increasing breast milk production: Insufficient clinical evidence specific to Blessed Thistle; general low-certainty evidence for some herbal galactagogues in improving lactation. Systematic reviews of clinical trials on herbal galactagogues indicate low to very low certainty evidence for increased milk volume with some herbs, but Blessed Thistle was not specifically studied or identified as effective in clinical trials. Higher-quality trials are needed to confirm any potential benefit.
Side Effects
There are no well-documented adverse effects specific to Blessed Thistle in clinical trials. Reported adverse effects in studies of herbal galactagogues in general include minor complaints such as tiredness, nausea, headache, dry mouth, and rare allergic reactions; however, these have not been confirmed specifically for Blessed Thistle.
Drug Interactions
No specific evidence exists concerning drug interactions with Blessed Thistle. Broad reviews of herb-drug interactions note that most herbal medicinal products are not associated with severe interactions, but data quality is generally poor, and no firm conclusions can be drawn for Blessed Thistle.
Who Should Avoid It
No specific contraindications for Blessed Thistle have been reported in the available clinical literature. However, due to insufficient evidence regarding safety, caution is advised for pregnant or breastfeeding women considering its use. Individuals with allergies to related plants or herbs should also exercise caution.
Evidence Limitations
Evidence is limited by a lack of high-quality, well-designed randomized controlled trials specifically investigating Blessed Thistle. Existing studies on herbal galactagogues face challenges including high risk of bias, heterogeneity in study design, small sample sizes, and imprecise outcome measurement. Safety data are generally insufficient, and adverse effects are likely underreported.
References
- Cragg A, Levene I, Darabi S, Willcox M. Herbal galactagogues to improve breastmilk production and lactation in mothers of preterm babies: a systematic review of clinical trials. 2026.
- Foong SC, Tan ML, Foong WC, Marasco LA, Ho JJ, Ong JH. Oral galactagogues (natural therapies or drugs) for increasing breast milk production in mothers of non-hospitalised term infants. Cochrane Database Syst Rev. 2020.
- Bazzano AN, Hofer R, Thibeau S, Gillispie V, Jacobs M, Theall KP. A Review of Herbal and Pharmaceutical Galactagogues for Breast-Feeding. 2016.
- Posadzki P, Watson L, Ernst E. Herb-drug interactions: an overview of systematic reviews. Br J Clin Pharmacol. 2013.
- Budzynska K, Gardner ZE, Dugoua JJ, Low Dog T, Gardiner P. Systematic review of breastfeeding and herbs. 2012.
- Bazzano AN, Littrell L, Brandt A, Thibeau S, Thriemer K, Theall KP. Health provider experiences with galactagogues to support breastfeeding: a cross-sectional survey. 2016.
Last Reviewed
June 2024
Disclaimer
This information is provided for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare provider before using any herbal supplement, especially during pregnancy or breastfeeding. Individual responses to herbal products can vary, and safety can depend on many factors including dosage and health status.