How does it feel?
As you press mint leaves from the garden the first impact is the minty aroma from its menthol. This is a key ingredient of the essential oil of the mint family (it is actually a crystalline solid oil at room temperature, though liquefies at body temperature, i.e. when we taste it). Menthol activates the same nerve receptors that cold does, so even when inhaled there is a sensation of cooling. Certainly the smell of mints is most often described in this way.
When you make a strong peppermint tea, again there is an immediate cooling effect of the menthol in the mouth. Then other sensations come through: there are more aromatic, almost pungent flavours as the other volatile oils work through to the palate. In the finish you will probably pick up the dryness of the astringent tannins, actually a large fraction of mint constituents.
What can I use it for?
Mints provide ideal herbal teas to try, for a wide range of digestive disorders including heartburn, dyspepsia, cramping, distension, colic and flatulence, nausea and vomiting. If mint is helpful there will be almost immediate relief and you can be encouraged to increase the strength: perhaps to two or more teabags per cup, steeped for at least 15 minutes (although note the different dosage effects in the next section). If it is not helpful there will be no harm done and you could try a different tea like chamomile, fennel, lemon balm or ginger for example, until you find the one that suits you best.
The benefits of peppermint oil in the treatment of irritable bowel syndrome are well-supported by clinical trials. It may also have stronger effects in relieving dyspepsia, nausea (so worth trying if mint teas are partially helpful), as well as gallbladder and bile ducts pain. In this case either use proprietary or prescription peppermint oil capsules, or add the oil to peppermint tea in stepped up levels from 3 to 8 drops. Peppermint oil must never be swallowed neat and should be used cautiously if you have inflammatory diseases of the digestive system or have gallstones.
Due to their menthol component, you will get some benefits for symptoms of coughs and colds from mint teas, particularly if you inhale the steam coming off the hot tea. A stronger effect however will be from inhaling peppermint oil, particularly with steam.
Mints are uplifting to the mood, yet likely to improve sleep if taken last thing before bed. There is evidence that mint teas can reduce palpitations or other cardiac consequences of anxiety.
Peppermint oil applied to the skin may relieve neuralgia, pruritus and headaches and can be considered to heal cracked nipples when breastfeeding.
Into the heart of mint
The mint family all have a high levels of essential oil containing menthol, which with another constituent menthone, gives the plant its distinctive scent and taste.
It is also the component responsible for mints’ medicinal activity. Menthol acts as an analgesic, working by cooling muscle, circulatory and other pains, also separately relieving the strain and tension that may contribute to pain and headaches.
In the digestive tract, menthol will reduce the contractile responses of the digestive muscles, certainly by stimulating cold receptors in the stomach and possibly by inhibition of calcium influx into the smooth muscle of the gut wall, so relieving heartburn, digestive cramping and colic and even by reflex calming excessive heart activity in anxiety, like palpitations. Menthol may even directly activate calming GABA receptors in the nervous system.
Confusingly the subjective effect of taking mint has sometimes been described ‘warming’ (‘pungent’ in some traditional descriptions). When taken, especially in high doses, during colds and fever it has diaphoretic properties, ie it encourages perspiration and feels warming to the person concerned. Nevertheless by increasing sweat production mints actually reduce fever and so the net effect remains cooling.
Menthol is a volatile aromatic and when inhaled can decongest and remove excessive levels of phlegm from the airways.
The dose and method of taking the remedy are important. A low dose is relaxing, a medium dose benefits inflammatory conditions and high dosages clear excess congestion.
Traditional uses
Mints have been traditionally used in the relief of digestive disorders, and to balance the effects of stronger remedies, especially stimulating laxatives. Their beneficial actions on the digestive system extend to the use of the tea for nausea, as well as morning and travel sickness. Members of the mint family are also widely used as diaphoretics (to stimulate perspiration in fevers and so help keep high temperatures in check – one reason why they are universally seen as ‘cooling’).
With a key constituent menthol, mints not surprisingly have also been widely used for respiratory symptoms, to clear nasal passages, to relieve coughing in bronchial conditions and pneumonia, and for the temporary relief of sore throats. They have also seen to promote digestive, kidney and liver detox functions. Women have used mint teas to relieve painful periods. Externally, peppermint oil has been used to relieve pain and itching, and as a mouthwash. Bruised fresh mint and peppermint oil have a use in relieving headaches. They have a reputation as mildly sedative, and were used in combination with other herbs to relieve nervous upsets. They also have a long history as flavouring agents for teas, medicines, food and drink.
Traditional actions
Herbal actions describe therapeutic changes that occur in the body in response to taking a herb. These actions are used to express how a herb physiologically influences cells, tissues, organs or systems. Clinical observations are traditionally what have defined these actions: an increase in urine output, diuretic; improved wound healing, vulnerary; or a reduction in fever, antipyretic. These descriptors too have become a means to group herbs by their effects on the body — herbs with a nervine action have become the nervines, herbs with a bitter action are the bitters. Recognising herbs as members of these groups provides a preliminary familiarity with their mechanisms from which to then develop an understanding of their affinities and nuance and discern their clinical significance.
Traditional energetic actions
Herbal energetics are the descriptions Herbalists have given to plants, mushrooms, lichens, foods, and some minerals based on the direct experience of how they taste, feel, and work in the body. All traditional health systems use these principles to explain how the environment we live in and absorb, impacts our health. Find out more about traditional energetic actions in our article “An introduction to herbal energetics“.
Chinese energetics
Western energetics
What practitioners say
The most useful role of peppermint is as a tea in the treatment of various digestive upsets. Individuals with dyspeptic, flatulent or colicky symptoms divide approximately evenly between those who are relieved by peppermint and those who are not. It is a simple first step for anyone to find out in which category they fall: if there is any relief at all from taking a cup of simple tea then it is worth making it stronger, by steeping the teabag for 15 minutes and possibly using two per cup. If there is no relief it probably is worth trying a ‘warming’ remedy like fennel or ginger instead. If peppermint is helpful then chamomile may also work and more substantial benefits made be had with the stronger ‘cooling’ digestive remedies, the bitters (eg dandelion, artichoke, gentian root or wormwood). Practitioners may use the oil, particularly in enteric-coated capsules, for bowel irritability and as an ingredient of liniments or other topical applications. However there are gentler and as effective oils for inhalation purposes (such as oils of pine and aniseed).
Digestion
Indicated in heartburn, nervous digestion, flatulence, bloating, IBS, ulcers, nausea and anorexia. The tea (though probably not the oil) can relieve gastritis and enteritis. The aromatic essential oils can help to alleviate morning sickness, vomiting and spasms in the gastrointestinal tract. The oil may relieve gallbladder pain, though should be used with caution with gallstones themselves.
Infections
Commonly used as a hot tea to influence diaphoresis (sweating) in colds and flu. Especially when also inhaled it can help unblock airways congestion and is indicated where the lungs are congested with catarrh and constricted by spasms, wheezing or asthma.
Mental health
Mint teas may relieve mental and emotional tension and especially cardiac effects of anxiety.
Women’s health
Indicated in menstrual congestion, pain and amenorrhoea due to its ability to reduce congestion in the body. There is some evidence to point to the use of the tea in PCOS and other hormonal problems.
Topical
Peppermint oil when applied to the skin can cool and soothe skin inflammation, hot flushes and allergic itching. It is a prime remedy to relive headaches and ‘hot’ neuralgic pain. It should be considered for cracked nipples in breastfeeding mothers.
Research
The vast majority of modern research literature for mints relates to peppermint oil. As a strong extract of the menthol-containing mint family, this supports all their traditional reputations to some extent (1). Peppermint oil exerts a significant antispasmodic, carminative effect on the gastrointestinal tract, with a range of evidence pointing to the relief of dyspepsia (2), stomach spasm (3) and nausea (4). There seems also to be an improvement in stomach performance generally (5). There is evidence that peppermint oil can reduce bloating, flatulent and colicky symptoms of irritable bowel syndrome (IBS) (6,7), with plausible mechanisms of action as an antispasmodic (8,9). This benefit extends to children (10), and more widely in helping children suffering from undifferentiated functional abdominal pain (11). Inhaling peppermint oil is sufficient to reduce nausea and vomiting (12).
Mints are demonstrably cooling (13,14). Their constituent menthol has this effect by acting on transient receptor potential (TRP) channels in sensory nerves, effectively stimulating ‘cold receptors’ in the stomach (15). The consequent cooling is systemic as well as local: for example, peppermint oil not only reduces heartburn faster (16), but also reduces heart rate and other cardiac consequences of anxiety (17). The cooling effect may in part explain the symptomatic relief of nasal congestion (18).
Topically, peppermint oil is analgesic (pain relieving) (19), and has been shown to be useful in the treatment of neuralgia and pruritis e.g. in shingles, as well as in the relief of headaches (20). As a healing agent, peppermint gel was shown to be a superior treatment for cracked nipples in breastfeeding mothers (21).
Inhaling peppermint oil was found to enhance memory and to increase alertness in healthy volunteers (22,23), and may also improve sleep quality (24).
In a notable exception to the peppermint oil dominance of the research literature spearmint leaf tea was found to decrease free testosterone and increase luteinizing hormone (LH), follicle-stimulating hormone (FSH) and oestradiol levels in mildly hirsute women, some with polycystic ovary syndrome (PCOS) (25).
Did you know?
After-dinner mints started out as simple home remedies to relieve indigestion: they can still be used for this purpose!
Additional information
Botanical description
Mints are perennial herbs distinguished easily by the fresh minty scent and taste of their leaves. All mints have creeping rhizomes, from which new shoots grow up to 50-60cm in height. (If you are growing mints you should use a container or bucket to prevent them encroaching on other plants.) Mint leaves are finely serrated, and like other labiates the stems of the plant are square. The flowers of mint plants are often a pale purple and will form tight whorls around the stem. Several members of the mint family were introduced to Britain by the Romans and have become naturalised throughout Europe, often found growing in the wild close to water or waste ground.
Many familiar mints are actually botanical hybrids. Peppermint (Mentha x piperita) is a hybrid of M. spicata (spearmint) – itself a hybrid of M. longifolia and M. suaveolens – and M. aquatica (water mint). The two most common cultivated varieties of peppermint are M. piperita var. vulgaris Sole (‘black mint’) and M. piperita var. officinalis Sole (‘white mint’). Black mint has darker purplish stems and purple-tinged leaves.
Alternate botanical names:
- Mentha piperata var vulgaris Sole (black peppermint)
- M. piperata var officinalis Sole (white peppermint)
- Mentha spicata (spearmint)
- Mentha aquatica (water mint)
Common names
- Peppermint
- Horsemint (Eng)
- Pfefferminze (Ger)
- Pfefferminzblätter (Ger)
- Katzenkraut (Ger)
- Edelminze (Ger)
- Englische Minze (Ger)
- Menthe anglaise (Fr)
- Menthe poivrée (Fr)
- Feuilles de menthe (Fr)
- Menta prima (Ital)
- Menta piemonte (Ital)
- Menta peperina (Ital)
- Hierbabuena (Sp)
- Pudina (Hindi)
- Puthia (Hindi)
- Paparaminta (Sanskrit)
- Bo he (Chin)
- Pak hom ho (Chin)
- Bok hoh (Chin)
- Heung-fa-chio (Chin)
- Xiang hua cai (Chin)
- Po ho (Chin)
Safety
Mints are very well tolerated, and adverse effects are mostly associated with peppermint oil, and may include contact dermatitis in some (26). However even here, a major review of the toxicity of peppermint oil as a cosmetic concluded that apart from sensitivity reactions the product was essentially safe, as long as pulegone content is kept below 1% (27).
Sensitivity reactions rarely occur in the mouth and airways: young children are more susceptible than adults. The oil should generally not be used as a topical application or neat inhalation in infants. Perianal burning occasionally occurs following ingestion of peppermint oil capsules – this may be due to rapid bowel transit time, and may be avoided with adjustment of dosage.
The tannin-content may be associated with gastrointestinal irritation in some individuals. One clinical trial suggests that, due to its tannin content, peppermint inhibited iron absorption by 84%. People with anaemia should be advised not to take peppermint simultaneously with meals or iron supplementation. Studies from Nigeria where glucose-6-phosphate deficiency is relatively common have associated menthol-containing skin applications with jaundice in infants with this deficiency.
There is no evidence of harmful effects from use in pregnant women although such evidence is limited. Mint is probably compatible with breastfeeding.
Dosage
6-9 g of dried leaf for therapeutic effect.
Constituents
- Essential oil (0.5–4%) consisting predominantly of menthol (35–45%) and (–)-menthone (10–30%)
- Tannins (6–12%)
- Flavonoids primarily eriocitrin, luteolin and hesperidin
- Triterpenes
- Bitter substances.
The most obvious constituent of mints is menthol, responsible for the majority of their therapeutic actions, although the flavonoid and tannin components are also significant. For example the tannins may add to the calming effect of mints in diarrhoea or other irritation of the bowel.
Recipe
Majestic Mint tea
When you make this lovely mint tea, the first thing you can feel is the immediate cooling effect of the menthol in the mouth. Then other sensations come through: there are more aromatic, almost pungent flavours as the other volatile oils work through to the palate. As the last sensation you will probably pick up the dryness of the astringent tannins.
Ingredients:
As many types of fresh mint as you can find (try peppermint, spearmint, horsemint and fieldmint) 10–20g, about 2 handfuls
This will serve 2–3 cups of minty tea.
Method:
Put all of the ingredients in a pot.
Add 500ml/18fl oz of freshly boiled filtered water.
Leave to steep for 5–10 minutes, then strain.
Some people like a little sweetener with the mint – honey works a treat.Let me glow tea
This delicious recipe is a healing blend of chlorophyll-rich herbs that purify the blood, soothe the liver and cleanse the skin, helping you glow from the inside out. Good for anyone with pimples, acne or other skin blemishes.
Ingredients:
- Nettle leaf 3g
- Fennel seed 2g
- Peppermint leaf 2g
- Dandelion root 2g
- Burdock root 2g
- Red clover 2g
- Turmeric root powder 1g
- Licorice root 1g
- Lemon juice a twist per cup
This will serve 2 cups of beautifying tea.
Method:
- Put all of the ingredients in a pot (except the lemon). Add 500ml (18fl oz) freshly boiled filtered water.
- Leave to steep for 10–15 minutes, then strain and add the lemon.
These recipes are from the book Cleanse, Nurture, Restore by Sebastian Pole
References
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- Thompson Coon J, Ernst E. (2002) Systematic review: herbal medicinal products for non-ulcer dyspepsia. Aliment Pharmacol Ther. 16(10): 1689–1699.
- Hiki N, Kurosaka H, Tatsutomi Y, et al. (2003) Peppermint oil reduces gastric spasm during upper endoscopy: a randomized, double-blind, double-dummy controlled trial. Gastrointest Endosc. 57(4):475–482
- Tate S. (1997) Peppermint oil: a treatment for postoperative nausea. J Adv Nurs. 26(3): 543–549.
- Inamori M, Akiyama T, Akimoto K, et al. (2007) Early effects of peppermint oil on gastric emptying: a crossover study using a continuous real-time 13C breath test (BreathID system). J Gastroenterol. 42(7): 539–542
- Khanna R, MacDonald JK, Levesque BG. (2014) Peppermint oil for the treatment of irritable bowel syndrome: a systematic review and meta-analysis. J Clin Gastroenterol. 48(6): 505–512.
- Grigoleit HG, Grigoleit P. (2005) Peppermint oil in irritable bowel syndrome. Phytomedicine. 12(8): 601–606
- Kligler B, Chaudhary S. (2007) Peppermint oil. Am Fam Physician. 2007;75(7):1027–1030
- Grigoleit HG, Grigoleit P. (2005) Pharmacology and preclinical pharmacokinetics of peppermint oil. Phytomedicine. 12(8): 612–616.
- Kline RM, Kline JJ, Di Palma J, Barbero GJ. (2001) Enteric-coated, pH-dependent peppermint oil capsules for the treatment of irritable bowel syndrome in children. J Pediatr. 138(1):125–128
- Anheyer D, Frawley J, Koch AK, et al. (2017) Herbal Medicines for Gastrointestinal Disorders in Children and Adolescents: A Systematic Review. Pediatrics 139(6): e20170062
- Sites DS, Johnson NT, Miller JA, et al. (2014) Controlled breathing with or without peppermint aromatherapy for postoperative nausea and/or vomiting symptom relief: a randomized controlled trial. J Perianesth Nurs. 29(1): 12–19
- Knowlton WM, McKemy DD. (2011) TRPM8: from cold to cancer, peppermint to pain. Curr Pharm Biotechnol. 12(1): 68–77
- Jordt SE, McKemy DD, Julius D. (2003) Lessons from peppers and peppermint: the molecular logic of thermosensation. Curr Opin Neurobiol. 13(4): 487–492
- Farco JA, Grundmann O. (2013) Menthol–pharmacology of an important naturally medicinal “cool”. Mini Rev Med Chem. 13(1): 124–131
- Strugala V, Dettmar PW, Sarratt K, et al. (2010) A Randomized, controlled, crossover trial to investigate times to onset of the perception of soothing and cooling by over-the-counter heartburn treatments. J Int Med Res. 38(2): 449–457
- Kazadi LC, Fletcher J, Barrow PA. (2018) Gastric cooling and menthol cause an increase in cardiac parasympathetic efferent activity in healthy adult human volunteers. Exp Physiol. 103(10): 1302–1308
- Eccles R, Griffiths DH, Newton CG, Tolley NS. (1988) The effects of menthol isomers on nasal sensation of airflow. Clin Otolaryngol Allied Sci. 13(1): 25–29
- Göbel H, Heinze A, Heinze-Kuhn K, et al. (2016) Oleum menthae piperitae (Pfefferminzöl) in der Akuttherapie des Kopfschmerzes vom Spannungstyp [Peppermint oil in the acute treatment of tension-type headache]. Schmerz. 30(3): 295–310
- Borhani Haghighi A, Motazedian S, Rezaii R, et al. (2010) Cutaneous application of menthol 10% solution as an abortive treatment of migraine without aura: a randomised, double-blind, placebo-controlled, crossed-over study. Int J Clin Pract. 64(4): 451–456
- Melli MS, Rashidi MR, Nokhoodchi A, et al. (2007) A randomized trial of peppermint gel, lanolin ointment, and placebo gel to prevent nipple crack in primiparous breastfeeding women. Med Sci Monit. 13(9): CR406–CR411
- Kennedy D, Okello E, Chazot P, et al. (2018) Volatile Terpenes and Brain Function: Investigation of the Cognitive and Mood Effects of Mentha × Piperita L. Essential Oil with In Vitro Properties Relevant to Central Nervous System Function. Nutrients. 10(8): 1029
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