Mint – a traditional remedy for digestive problems

Mint (Mentha longifolia) is probably the most popular herb that is consumed as both an herb and an infusion. It has a mild, refreshing flavour, but also numerous healing properties that have been extensively researched. Its medicinal qualities come from its leaves and stems, with most of the active ingredients concentrated in the essential oil extracted from this valuable plant. In addition to as an infusion and oil, mint extract is also often used, especially in pharmaceutical preparations. The leaves and stems can be used to make an infusion or as a flavouring for various meat dishes. Mint is also widely used in skin and hair care cosmetics, and in the production of insecticides and anti-microbial agents.

Although it has been used in traditional medicine for millennia, its various properties are still being researched, and these are consistently confirmed by numerous scientific studies. We always start from biologically active ingredients that have real healing properties. These are mostly flavonoids and phenolic compounds, followed by flavanols such as catechin, epicatechin and coumarins. The essential oil contains alcohols, ketones, esters, ethers and oxides. Most people probably know that one of the basic constituents of mint is menthol. Menthol has a variety of medicinal properties, but its highest concentration is in essential oils, where it can reach up to 90%. When used for therapeutic purposes, the menthol content in the oil should be between 30% and 55%. It is precisely because of its varied composition that mint has so many medicinal properties, and thus in addition to as an infusion and oil there are many other mint-based medicinal preparations, such as capsules, tablets, salves, creams, lotions, shampoos, and so on. All these preparations have different ingredients and concentrations of mint in their formulas.

Thanks to its rich composition, mint has analgesic, antimicrobial, anti-inflammatory, and antioxidant properties, which can be harnessed for the prevention of diabetes, cardiovascular diseases, chronic degenerative diseases, and the control of inflammation. However, it is most commonly used in the form of oil, which acts as a neurostimulant, with studies confirming that it improves cognitive abilities and can even act as a painkiller. When applied to the skin, it creates a cooling sensation and a mild analgesic effect. Mint dilates the blood vessels and can help regulate high blood pressure, which is why it is often recommended as an infusion for hypertension. As it relaxes the bronchial tubes and helps to expel mucus, a mint infusion is a great ally during the winter months. There is also ongoing research into the anti-tumour effects of mint oil. As far as antibacterial action is concerned, mint oil and extract inhibit both Gram-positive and Gram-negative bacteria. This means that mint has an effect on a broad range of microorganisms that can be harmful to humans.

However, the best known effects and uses of mint are undoubtedly related to the digestive tract. Mint has long been known as a plant that relieves stomach discomfort and various digestive problems. Today’s sedentary way of life, along with diets that are low in fibre and high in saturated fats and simple sugars, contribute to frequent digestive problems manifested as poor digestion, bloating, gas, a feeling of heaviness, and pain. Mint helps with the sensation of food lingering in the stomach and reduces the post-meal feeling of heaviness. It is thought to stimulate the secretion of digestive enzymes, which aids the digestive process as a whole. It acts as a carminative, supporting the function of the intestines. Mint oil or infusion can thus help to alleviate the feelings of bloating and gas that often occur when the bowel slows down. It is also effective for stomach aches and morning sickness. Pregnant women can relieve nausea just by smelling or chewing a few mint leaves.

Irritable bowel syndrome (IBS) is now a very common disease. Typical symptoms include diarrhoea or chronic constipation, pain, and often a lack of nutrients from food. IBS can thus significantly reduce the quality of life. However, mint oil contains menthol, which relaxes the smooth muscles of the digestive tract, relieving the symptoms of IBS. Remarkably, participants in studies examining the efficacy of mint oil reported an improvement in IBS symptoms within just two weeks, which is a very short time for the treatment of digestive diseases. It should be noted that meta-analyses found very few side effects, and those that existed were mild and temporary. Mint-based preparations thus have great potential in the treatment and management of IBS.

In addition to the relaxing effect of mint oil in treating IBS, there is another potentially beneficial property of mint, namely its antimicrobial effect on the gut microflora. The progression of IBS is very complex, and several causes have been identified so far, one of which is the proliferation of pathogenic bacteria in the gut, the products of which then cross into the bloodstream. Given that mint oil is known for its antibacterial action, its use in IBS could be very beneficial.

Mint essential oil and leaf infusion can also help with gas and bloating, as well as mild intestinal cramps. Mint oil also stimulates digestive enzymes, promotes bile secretion, and improves digestion. Better digestion of food allows better absorption of nutrients. When the body is able to absorb nutrients, metabolism also speeds up. According to some studies, a faster metabolism can help with weight loss.

Animal studies show that mint can have a protective effect on the liver and reduce the symptoms of arsenic poisoning. These studies also show that when used in a water solution, mint can reduce the release of histamine, which in turn produces an anti-allergic effect. Other studies suggest that mint may also have a preventive effect by inhibiting the formation of kidney stones through its diuretic and antispasmodic action.  Mint extract affects the expression of genes that are important for wound healing. Studies carried out on rats show that mint extract stimulates healing, shortens the inflammatory phase, and speeds up scarring.

Mint has traditionally been used to calm the nervous system, reduce anxiety and restlessness, which can help improve the quality of life in the context of modern lifestyles full of rushing and deadlines. A mint infusion is recommended as a natural sedative for migraines and headaches, and for improving concentration and memory.

However, just because mint is a natural product does not mean that every infusion or oil is safe, or that it is suitable for everyone. The source plants may have been contaminated with pesticides, which should be taken into account when buying mint or mint oil. Some people may be allergic to mint, and can experience hypersensitivity, contact dermatitis, stomach pain, heartburn, a burning sensation in the perianal region, bradycardia, and even muscle tremors. In others, inhalation of menthol can cause apnoea, the temporary cessation of breathing. Mint oil is contraindicated in cases of bile duct obstruction and liver disease. It is also not recommended for digestive problems such as heartburn and acid reflux. This is because menthol relaxes the smooth muscles and consequently the lower oesophageal sphincter, which can intensify the backflow of acid into the oesophagus.

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