Mint-The herb that refreshes mouth, brain and body

Mint belongs to the Labiatae (Lamiaceae) family and is classified in the genus Mentha spp. So, it is closely related to plants such as sage, marjoram, basil, lavender, rosemary and thyme which are often used for essential oil production. The genus Mentha covers approximately 25–30 species. Mint has more than 101 local names in different countries¹⁵ some of the most known ones are M. officinalis, M. piperita (peppermint), M. spicata (spearmint), M. arvensis (wild mint), M. spicata crispa (curled mint), M. Canadensis (American mint), M. aquatica (bergamot). As in many other herbs, the amount of compounds that mint plants contain is different in various species and depends on various factors including physiological variations, environmental conditions, geographic differences and genetic factors¹⁹. Mentha species is widely cultivated in Australia, Eurasia and South Africa^{4, 5}.  Since the very ancient times mint has been commonly used in the kitchen not only for its great aroma and flavor, but also for providing relief from common colds, fever, flu, indigestion and motion sickness.

Health benefits

Great antioxidant/anti-inflammatory and anti-cancerous activity

There are many studies that have checked the leaves of several mint species (M. piperita, M. spicata, M. arvensis, M. Longifolia, and M. pulegium) and proved that they have high content of antioxidants like phenolics and flavonoids, such as eugenol and α-tocopherol^{3, 26}.

The essential oil of M. spicata contains also a molecule, named s-carvone, which is a great antioxidant⁷. Comparison between different Mint species (M. aquatica, M. haplocalyx, M. dalmatica, M. verticillata, M. spicata, and M. piperita) also showed that M. piperita has the most effective antioxidant activity.

Neuroprotective and neurochemical properties of mint extracts

There are two very interesting studies that showed the positive effect of mint on the Central Nervous System (CNS). In one study¹⁴, the researchers tested extracts of several mint species (M. aquatica, M. longifolia, M. pulegium, M. suaveolens and M. piperita) regarding their antioxidant activity on PC12 cells (primitive nerve cells) as well as other neurochemical properties. According to this study, the mint extracts could significantly protect the PC12 cells from oxidative damage and demonstrate promising effects on the CNS. In the other study, the essential oil of mint was given to 24 different participants and it was shown that their ability to perform difficult cognitive tasks was increased and that their mental fatigue was reduced.

Linarin, a compound from Mentha arvensis was proved to be an effective selective acetylcholinesterase inhibitor¹⁸. This inhibitor is often targeted for the therapy of myasthenia gravis and Alzheimer’s disease.

Finally, the compound viridiflorol from Mentha aquatica was shown to have affinity to the GABA-benzodiazepine receptor, a receptor often targeted for the therapy of Alzheimer’s disease¹⁰.
From all the above, it seems that consuming mint can help us improve our brain function as well as prevent Alzheimer’s disease.

Very good antiviral and antibacterial activity

Menthol, is a well-known mint compound that gives a refreshing feeling to your mouth and your brain every time that you consume mint. Apart from that, menthol and other mint compounds like carvone, have great antimicrobial activity, against several bacteria (Gram + or Gram -) and fungi. According to these studies, the extracts obtained from mint leaves are more effective comparing to the ones obtained from mint stems. Thus, compounds obtained from Mentha leaves are toxic for several bacteria, as well as fungi and could be a promising alternative to antibiotics, as well as very useful for food preservation^{2, 6, 8, 21, 24, 25}.

Interestingly, Mint compounds are also effective against certain viruses. Herpes simplex virus type 1 (HSV-1) is an orally transmitted virus (through the saliva) and Herpes simplex virus type 2 (HSV-2) is a sexually transmitted virus. Both types of infections are lifelong and in most of the cases they are asymptomatic. However, some of the symptoms include painful blisters or ulcers. On the top of that, people infected with HSV-2 are in higher risk of acquiring and transmitting HIV to others or their babies or suffer from urogenital infections²². Although there is a vaccine against the Herpes virus nowadays, it is useful to know that according to scientific studies the essential oil of mint, at high concentrations, is also effective against Herpes²³.

Great for the stomach, the gut and the liver

Mint decoction has been used since the ancient times as a home remedy for digestive and gastrointestinal problems. Science has proved through animal studies that mint relaxes the gastrointestinal (GI) tissue¹⁶ and also protects the liver from damage¹⁷. Mint also increases the secretions of the saliva, the bile, as well as the stomach and affects the function of the digestive enzymes of the small intestine¹².

This is why in many countries around the world the water from boiled mint leaves is commonly used against diarrhea and indigestion. It has also been proved scientifically that enteric coated peppermint oil (ECPO) is very effective against the symptoms of the irritable bowel syndrome (IBS)²⁰. ECPO is also effective against Helicobacter pylori, Candida albicans and gastroesophageal reflux disorder^{13, 22}.

Attention!

Safety Overview: Peppermint and peppermint oil are widely consumed as common food and flavoring ingredients. However, overdoses of peppermint oil are possible and near-fatal situations have occurred due to menthol’s anesthetic properties^{1, 9}.

Tips and tricks

• Fresh mint gives a refreshing flavor to your dishes. Use it with together with endives, yoghurt or soft white cheese.
• Dry mint is great as tea but also to accompany some of your dishes like beans, pies or burgers.
• Mint tea is very effective against fatigue and drowsiness. It really works better than coffee! The caffeine content (14.30 g/L) of mint tea is very low comparing to a cup of coffee (95mg), which makes it also a perfect hot beverage during pregnancy. 

Fun (historical) facts

• Peppermint and its essential oil are being used since the ancient times as flavoring agents in foods, liqueurs, and confectionaries.
• Peppermint oil is the fifth most produced essential oil in the world, and the peppermint plant is one of the most studied sources of essential oils¹.
• The United States, China and India lead the world as peppermint producing countries¹; others are Morocco, Argentina, Bulgaria and Georgia (FAO 2015).

References