Zam W, Quispe C, Sharifi-Rad J, et al. An updated review on the properties of Melissa officinalis L.: not exclusively anti-anxiety. Front Biosci (Schol Ed). June 7, 2022;14(2):16. doi: 10.31083/j.fbs1402016.
Lemon balm (Melissa officinalis, Lamiaceae) is used in traditional systems of herbal medicine for its beneficial effects on the central nervous system, such as sedation and memory improvement. Its volatile oils, triterpenes, and phenolic compounds are responsible for most of its benefits, including its antioxidant, antibacterial, and anti-inflammatory properties. The results of some studies suggest that lemon balm may help manage diseases such as diabetes mellitus and Alzheimer's disease. In their review, these authors aimed to gather information on botany and phytochemistry, traditional medicinal, and ethnopharmacological uses of lemon balm and its clinical aspects and biomedical properties.
Lemon balm is used widely in food, medicine, and cosmetics because of its valuable phytochemicals, including volatile compounds (such as neral, geranial, citronellal), phenolic acids (such as rosmarinic acid), and flavonoids (such as luteolin), and others.
Among the reported health benefits of lemon balm are its anxiolytic, antioxidant, antidepressant, anticancer, antinociceptive, anti-epileptic, anti-angiogenesis, antimicrobial, anti-inflammatory, antiviral, hypolipidemic, and hypoglycemic properties.
The authors identified several preclinical studies reporting that lemon balm possessed antiviral activity against a number of viruses, including COVID-19, influenza, herpes simplex virus types 1 and 2, HIV, and enterovirus 71. Other beneficial activities of lemon balm have been reported to be antimicrobial properties against Staphylococcus aureus, Escherichia coli, Shigella sonei, S. epidermidis, and Salmonella typhimorium, among others. The plant's essential oils demonstrated antifungal activities against Candida albicans, C. krusei, and C. glabrata. Because of its anti-inflammatory properties, lemon balm was effective in relieving symptoms of atopic dermatitis. A nephroprotective activity against acetaminophen-induced lesions and an anti-inflammatory effect on carrageenan-induced pleurisy were associated with the use of lemon balm in animals. Its neuroprotective properties were demonstrated in studies showing that crude ethanol extracts of lemon balm and its fractions blocked acetylcholinesterase in vitro and in vivo providing some mechanistic support regarding the putative calming effects of lemon balm. In cytotoxicity assays, lemon balm was effective in protecting against hypoxia in cultured neurons. Lemon balm oil lowered malondialdehyde levels and attenuated a decrease of antioxidant capacity in the hippocampus in vivo.
Clinical trials have focused on the effects of lemon balm extracts against various diseases, mostly related to neurological disorders, but also metabolic problems and infantile colic (especially, when combined with chamomile, fennel, and other botanicals). For centuries, lemon balm was used to improve memory, cognition, anxiety, depression, and heart palpitations. The effectiveness of lemon balm against heart palpitations and in improving memory, anxiety, brain function, and sleep quality has been verified in human studies. In studies of children, lemon balm reduced sleep bruxism.
Other reported benefits of lemon balm include improvement in hypoactive sexual desire disorder in women; decrease in serum triglyceride levels in dyslipidemic diabetic patients; modulation of fasting blood sugar, glycated hemoglobin, and systolic blood pressure in type 2 diabetes patients; decrease in blood pressure in hypertensive patients; and reductions in low-density lipoprotein and aspartate transaminase levels in hyperlipidemia patients. In two cited studies, crying time significantly decreased in children with infantile colic treated with lemon balm.
While the authors caution that lemon balm can exert toxicity if not used correctly, none of the data presented in the review suggests that lemon balm is toxic. They present some data on cytotoxicity against cancer cells; the cytotoxicity against hepatocells and neurotoxicity was with the essential oil; most essential oils are cytotoxic in some way. but is not related to the herb itself, which should have been stated more clearly by the authors. Other studies showed neuroprotective effects. Several randomized, controlled trials using various treatment regimens of lemon balm extracts reported no adverse effects in humans. Although the toxicity data on lemon balm are scarce, "available data point out its putative safety in human beings," write the authors.
According to the authors, "this review sheds new light on the potential of M. officinalis and encourages researchers to increase the therapeutic possibilities of this medicinal plant." However, there have been a number of reviews on lemon balm previously that cover much of the same literature, most notably the review Shakeri A, Sahebkar A, Javadi B.1
The authors declare no conflicts of interest.
—Shari Henson
Reference
1Shakeri A, Sahebkar A, Javadi B. Melissa officinalis L. - A review of its traditional uses, phytochemistry and pharmacology. J Ethnopharmacol. July 2016;188:204-28. doi: 10.1016/j.jep.2016.05.010.