by Dimitra Makarona

Abstract

A popular culinary ingredient, Melissa officinalis, commonly known as lemon balm, is greatly appreciated in many parts of the world for its invigorating minty scent and the lemony kick that gives to salads and fish dishes. Lemon balm has a good safety profile and it has been used therapeutically for centuries. Modern studies support its positive effect on agitation, cognitive function and viral infections rendering it a plant with a great potential in the field of pharmaceutical discovery. Lemon balm is in abundance in the beautiful Mecklenburgh Square Gardens and nature lovers could spot it in the south and south-west flower beds surrounding the square. In fact, it is a rather ‘weedy’ plant and spreads easily.

Introduction

Melissa officinalis L.(lemon balm), is a valuable member of the mint family (Lamiaceae). The plant leaves have been used in cooking for longer than 2000 years thanks to their refreshing, lemony and minty fragrance. However, lemon balm is not only used for culinary purposes, but it is also followed by a long history of therapeutic use. Quite often it is combined with sage and rosemary for the preparation of a strong, hot beverage. These are thought to soothe the symptoms of the common cold. In the first century AD, the Greek physician and botanist Pedanius Dioscorides compiled all the information known about ‘every healing substance’ used and compiled De materia medica (Shakeri, A. et al.,2016). Dioscorides was the first known person who referred to the medicinal uses of lemon balm and since then, relevant information was included in books of folk medicine and the greatest pharmacopoeias of the world.

How does the lemon balm look like and where can you find it?

Lemon balm is a perennial plant and its height ranges from 30 cm to 125 cm. Short fine hairs are extended to all parts of the plant apart from the stem, which is erect and branched. (Shakeri, A. et al.,2016). The leaves are bright green and oval-shaped, whilst the texture of their surrounding is serrated. They usually are 3 cm wide and 6 cm long.

It blooms during summer and the white, nectar-filled flowers form clusters of half to a full dozen of blossoms. The aerial parts of the herb die in winter, but in the beginning of spring they rejuvenate owing to its strong hairy root system.

Botanists are not certain about the origin of lemon balm, but the eastern Mediterranean countries, West Africa, Northern Iran and Caucasus region are considered possible places of origin. It was officially introduced to Spain around the 7th century AD and its cultivation subsequently expanded throughout Europe. It reached North America during colonisation. Nowadays, it can be found globally, and it is a popular ornamental plant.

Is it called by other names? And where does the name Melissa derive from?

Lemon balm can also be found in the bibliography under the names of sweet balm, sweet Mary, dropsy plant, cure-all, melissa and honey plant. The genus name Melissa derives from the Greek word “melissa” (μέλισσα), meaning bee. This is due to the fact that bees are allured by the flower and fest on their nectar. This action leads to the production of excellent quality lemon balm honey. It is also worth mentioning that the epithet “officinalis”, established by the famous Swedish botanist and taxonomist Linnaeus, means that the lemon balm was a medicine recognised by medieval apothecaries

Traditional uses

Lemon balm was used for centuries in the European and Iranian traditional medicines’ systems and it was supposed to treat a wide variety of illnesses and discomforts. The ancient Greeks applied a mixture of wine and lemon balm on dressings in order to sterilise wounds (Blumenthal, M.,2000). The Romans were using a strong lemon balm extract locally, so as to tackle spider and scorpion bites. Dioscorides, the father of pharmacology believed that lemon balm was an antidote for mushroom toxicity. It could soothe breathing difficulties, bowel ulcers, flatulence and musculoskeletal pain. It was also considered a powerful remedy for the initiation of menstruation (i.e. emmenagogue).

During the medieval period, lemon balm was recommended for morning sickness, toothache, earache and baldness. Moreover, it was supported that it improved memory, cognitive function and it prolonged life expectancy.

In Austria, lemon balm was used in the form of a tea or externally as an essential oil for the treatment of intestinal discomfort of liver diseases. It would be very interesting to note that in Danish folk medicine, this herb was used to treat lethargy caused by a broken heart, deep sorrow or melancholy (Adsersen, A. et al, 2006). Spanish culture was using it as a painkiller and emmenagogue, whilst Croatians appreciated it greatly as a remedy for cough and sore throat. Lebanese physicians claimed that it promotes cardiac function and it relieves migraines and stomach cramps. Lemon balm was as essential herb for the Iranian Traditional Medicine and it was frequently used to treat depression, anxiety and symptoms of psychosis. Its use also ranged from the treatment of diabetes and mouth ulcers to cancer and rabies. Finally, the value of lemon balm was also recognised in the Indian traditional medical system of Ayurveda, which promoted it as a memory enhancer.

What about modern times? Are the contemporary indications proven scientifically?

Chemical analysis of extracts containing lemon balm revealed that it consists of many chemical compounds that could indeed have a therapeutic effect. Some of these compounds include the flavonoid luteolin, the phenolic compound rosmarinic acid and the terpenes: citronellal, eugenol, neral and geranial.

Pharmacological studies conducted in mice show that lemon balm oil alleviates agitation by binding to serotonin, muscarinic and histamine receptors. These are the brain receptors where anxiolytic drugs normally bind to and exert their effect. It was also proven that the calming effect of lemon balm was superior to that of lavender. (Abuhamdah, S. et al.,2008; Huang,L.,2008 )

In addition, lemon balm improves the quality of life of patients suffering from Alzheimer’s disease. A lotion containing 10% lemon balm was tested against a non-active placebo and a third treatment containing donepezil (Burns, A. et al.,2011). Donepezil is a drug commonly administered in Alzheimer’s disease in the form of patch. The results showed no improvements on the agitation of patients applying lemon balm lotion, but their quality of life was ameliorated. However, previous studies have shown that aromatherapy treatment with lemon balm essential oils led to lower agitation levels in Alzheimer’s patients (Heinrich,M. & Jäger, A., 2015). Thus, we could say that anxiolytic use of lemon balm is supported by a series of clinical studies and its long-history use for this purpose.

A different study revealed that the regular intake of a mixture containing sage, rosemary and lemon balm showed promising results, since it improved the memory of demented patients. There was no evidence though about the separate effect of the ingredients. Therefore, we cannot be sure if all three of them are beneficial or the positive effect could be owing to one or two of them (Perry, N.S.L. et al.,2018).

In modern times, concentrated lemon balm oil is highly esteemed for its antiviral properties. It is brilliant for the relief of cold sores, which are caused by the herpes simplex virus. Lemon balm was compared to conventional treatment, such as acyclovir cream and it resulted in reducing the lesion healing time in half. Lemon balm cream can also be used prophylactically, for the prevention of herpes infection outbreaks (Bone, K. and Mills, S., 2013).

Finally, lemon balm essential oil has a carminative impact and alleviates colic and flatulence. Scientists support that it could comfort patients suffering from irritable bowel syndrome (IBS) and have symptoms, like dyspepsia, constipation, diarrhoea or trapped wind. It could also benefit their general mental health and deal with symptoms of anxiety which are often associated with bowel conditions. The effect of the essential oil is enhanced if it is added in hot water and drunk as a brew. A few studies were completed where infants suffering from colic pains participated. The babies were given herbal instant tea preparations including a mixture of ingredients, such as lemon balm, chamomile, licorice, fennel and in some cases additional vitamins B1 and B6. Since the babies were about three weeks old and could not provide any feedback the frequency and amount of crying was observed and recorded. Crying was reduced by over 60% and in some cases the colic was eliminated (Savino, F. et al.,2005; Weizman, Z.V.I. et al.,1993).

What is the vision for the future?

A recent study performed at a hospital in Tehran, Iran claims that lemon balm could reduce LDL (bad cholesterol) levels in patients with mild hypercholesterolemia. 64 males participated in the study for two months and 32 of them received a 500mg dose of capsules containing lemon balm powder three times daily. The other group was administered the same dose of capsules containing starch powder as a placebo medication. In the end of the treatment course, the blood samples of the individuals receiving lemon balm showed significantly lower cholesterol levels, LDL in particular, in comparison to the placebo group (Jandaghi, P et al.,2016). These results are very encouraging as they could potentially lead to a new naturally derived treatment for high cholesterol.

Is lemon balm safe to use?

Preparations containing lemon balm are generally considered safe and they can be used or consumed daily unless someone is allergic to it. However, there are a few exceptions to that rule. Melissa officinalis extracts could increase thyroid hormone levels in the body and as a result, patients suffering from thyroid disorders should avoid them (Bone, K. & Mills, S., 2013). It could enhance the sedative effect of many anxiolytic drugs and tranquilisers and for that reason it should not be consumed by patients receiving this type of medication.

Conclusions

All in all, lemon balm is a medicinal plant with a very long history of use and modern research has provided considerable evidence for such “old-fashioned” indications. It has been proven to be very useful as a topical treatment for cold sores and its action on the nervous system has been studied extensively. The lives of patients suffering from dementia have been enhanced in the context of clinical studies and its essential oil seems to trigger positive feelings by reducing stress levels. People suffering from gastrointestinal symptoms could observe a great, positive change by incorporating this herb in their daily diet thanks to its proven soothing effect.

No one can doubt that lemon balm is not only useful in the kitchen as a culinary ingredient, but it also has a wide therapeutic action. All the traditional knowledge and the clinical studies completed, hint that nature hides numerous gems in the presence of plants that could lead to major drug discoveries.

Disclaimer: In this essay we do not advise or recommend herbs for medicinal or health use. This information is intended for educational purposes only and should not be considered as a recommendation or endorsement of any particular medical or health treatment. The use of any such product should be based on the appropriate advice of a healthcare professional or based on the information available in the patient information leaflets (i.e. for THR products).

 © Dimitra Makarona 2019. All rights reserved.

Dimitra Makarona is a pharmacist registered with General Pharmaceutical Council of Great Britain and an MSc student in Natural Medicinal Products and Phytochemistry at the UCL School of Pharmacy.

References

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Adsersen, A., Gauguin, B., Gudiksen, L. and Jäger, A.K., 2006. Screening of plants used in Danish folk medicine to treat memory dysfunction for acetylcholinesterase inhibitory activity. Journal of ethnopharmacology, 104(3), pp.418-422.

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Burns, A., Perry, E., Holmes, C., Francis, P., Morris, J., Howes, M.J.R., Chazot, P., Lees, G. and Ballard, C., 2011. A double-blind placebo-controlled randomized trial of Melissa officinalis oil and donepezil for the treatment of agitation in Alzheimer’s disease. Dementia and Geriatric Cognitive Disorders, 31(2), pp.158-164.

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Jandaghi, P., Noroozi, M., Ardalani, H. and Alipour, M., 2016. Lemon balm: A promising herbal therapy for patients with borderline hyperlipidemia—A randomized double-blind placebo-controlled clinical trial. Complementary Therapies in Medicine, 26, pp.136-140.

Perry, N.S.L., Menzies, R., Hodgson, F., Wedgewood, P., Howes, M.J., Brooker, H.J., Wesnes, K.A. and Perry, E.K., 2018. A randomised double-blind placebo-controlled pilot trial of a combined extract of sage, rosemary and melissa, traditional herbal medicines, on the enhancement of memory in normal healthy subjects, including influence of age. Phytomedicine, 39, pp.42-48.

Savino, F., Cresi, F., Castagno, E., Silvestro, L. and Oggero, R., 2005. A randomized double‐blind placebo‐controlled trial of a standardized extract of Matricariae recutita, Foeniculum vulgare and Melissa officinalis (ColiMil®) in the treatment of breastfed colicky infants. Phytotherapy Research 19(4), pp.335-340.

Shakeri, A., Sahebkar, A. and Javadi, B., 2016. Melissa officinalis L.–A review of its traditional uses, phytochemistry and pharmacology. Journal of Ethnopharmacology, 188, pp.204-228.

Weizman, Z.V.I., Alkrinawi, S., Goldfarb, D.A.N. and Bitran, C., 1993. Efficacy of herbal tea preparation in infantile colic. The Journal of Pediatrics, 122(4), pp.650-652.