Robin Harford While Crataegus monogyna (hawthorn) fruits and flowers are generally safe for food use, some cautions and potential adverse effects should be considered, especially with prolonged or high intake.
Safety Profile and General Cautions
Most research indicates that the toxicity of C. monogyna is negligible, and it has a long history of safe use as food and in traditional medicine (Nabavi et al., 2015; Cui et al., 2023; Zhang et al., 2022). However, mild adverse effects have been reported in clinical studies of hawthorn preparations, including dizziness, gastrointestinal complaints (such as nausea), headache, and palpitations. Severe adverse events are rare but have been documented, particularly with concentrated extracts or in combination with other medications (Daniele et al., 2006; Nabavi et al., 2015).
Specific Concerns and Interactions
- Blood-Thinning Effects: Both the flowers and fruits contain compounds that can prolong blood coagulation and have anticoagulant properties. This may increase bleeding risk, especially for individuals taking anticoagulant or antiplatelet medications, or those undergoing surgery (Pawlaczyk-Graja, 2018; Rababa’h et al., 2020).
- Potential Genotoxicity: Some studies suggest that fruit extracts may have weak genotoxic (DNA-damaging) effects in animal and cell models, indicating that excessive or prolonged use should be approached with caution (Martinelli et al., 2021).
- Drug Interactions: Hawthorn may interact with cardiovascular drugs, especially those affecting blood pressure or heart rhythm, due to its cardioprotective and vasodilatory effects (Nabavi et al., 2015; Daniele et al., 2006).
- Allergic Reactions: As with any plant product, allergic reactions are possible, though rare (Daniele et al., 2006).
Key Adverse Effects Reported in Clinical Studies
| Adverse Effect | Frequency/Severity | Citations |
|---|---|---|
| Dizziness/Vertigo | Mild to moderate | (Daniele et al., 2006) |
| Gastrointestinal upset | Mild to moderate | (Daniele et al., 2006) |
| Headache/Migraine | Mild to moderate | (Daniele et al., 2006) |
| Palpitations | Mild to moderate | (Daniele et al., 2006) |
| Severe events | Rare, with extracts | (Daniele et al., 2006) |
Figure 1: Table summarizing adverse effects of Crataegus monogyna in clinical studies.
Conclusion
Crataegus monogyna fruits and flowers are widely regarded as safe for most people when consumed as food. However, individuals with bleeding disorders, those on blood-thinning or cardiovascular medications, or those planning surgery should exercise caution. Prolonged or excessive use, especially of concentrated extracts, may carry additional risks. Always consult a healthcare provider if you have underlying health conditions or are taking medications.
Dig deeper. Hawthorn: A Foraging Guide to Its Food, Medicine and Other Uses
References
Nabavi, S., Habtemariam, S., Ahmed, T., Sureda, A., Daglia, M., Sobarzo-Sánchez, E., & Nabavi, S. (2015). Polyphenolic Composition of Crataegus monogyna Jacq.: From Chemistry to Medical Applications. Nutrients, 7, 7708 – 7728. https://doi.org/10.3390/nu7095361
Pawlaczyk-Graja, I. (2018). Polyphenolic-polysaccharide conjugates from flowers and fruits of single-seeded hawthorn (Crataegus monogyna Jacq.): Chemical profiles and mechanisms of anticoagulant activity.. International journal of biological macromolecules, 116, 869-879. https://doi.org/10.1016/j.ijbiomac.2018.05.101
Martinelli, F., Perrone, A., Yousefi, S., Papini, A., Castiglione, S., Guarino, F., Cicatelli, A., Aelaei, M., Arad, N., Gholami, M., & Salami, S. (2021). Botanical, Phytochemical, Anti-Microbial and Pharmaceutical Characteristics of Hawthorn (Crataegus monogyna Jacq.), Rosaceae. Molecules, 26. https://doi.org/10.3390/molecules26237266
Zhang, J., Chai, X., Zhao, F., Hou, G., & Meng, Q. (2022). Food Applications and Potential Health Benefits of Hawthorn. Foods, 11. https://doi.org/10.3390/foods11182861
Cui, M., Cheng, L., Zhou, Z., Zhu, Z., Liu, Y., Li, C., Liao, B., Fan, M., & Duan, B. (2023). Traditional uses, phytochemistry, pharmacology, and safety concerns of hawthorn (Crataegus genus): A comprehensive review.. Journal of ethnopharmacology, 117229. https://doi.org/10.1016/j.jep.2023.117229
Rababa’h, A., Yacoub, O., El-Elimat, T., Rabab’ah, M., Altarabsheh, S., Deo, S., Al-Azayzih, A., Zayed, A., Alazzam, S., & Alzoubi, K. (2020). The effect of hawthorn flower and leaf extract (Crataegus Spp.) on cardiac hemostasis and oxidative parameters in Sprague Dawley rats. Heliyon, 6. https://doi.org/10.1016/j.heliyon.2020.e04617
Daniele, C., Mazzanti, G., Pittler, M., & Ernst, E. (2006). Adverse-Event Profile of Crataegus Spp.. Drug Safety, 29, 523-535. https://doi.org/10.2165/00002018-200629060-00005