Peppermint has a long tradition of medicinal use, with archaeological evidence placing its use at least as far back as ten thousand years ago.^{[citation needed]}

Peppermint has a high menthol content, and is often used as tea and for flavouring ice cream, confectionery, chewing gum, and toothpaste. The oil also contains menthone and menthyl esters, particularly menthyl acetate.^[12] Dried peppermint typically has 0.3-0.4% of volatile oil containing menthol (7-48%), menthone (20-46%), menthyl acetate (3-10%), menthofuran (1-17%) and 1,8-cineol (3-6%). Peppermint oil also contains small amounts of many additional compounds including limonene, pulegone, eucalyptol, caryophyllene and pinene.^[13][14] It is the oldest and most popular flavour of mint-flavoured confectionery. Peppermint can also be found in some shampoos, soaps and skin care products. Menthol activates cold-sensitive TRPM8 receptors in the skin and mucosal tissues, and is the primary source of the cooling sensation that follows the topical application of peppermint oil.^[15] Used in this way, it has been known to help with insomnia.

 

One animal study has suggested that Peppermint may have radioprotective effects in patients undergoing cancer treatment.^[16]

 

The aroma of peppermint has been found to enhance memory.^[17] As such, it can be administered by instructors to their students before examinations, to aid recall.^[17]

 

Peppermint flowers are large nectar producers and honey bees as well as other nectar harvesting organisms forage them heavily. A mild, pleasant varietal honey can be produced if there is a sufficient area of plants.

 

Peppermint oil

 

Peppermint oil has a high concentration of natural pesticides, mainly menthone.^[18]

 

In 2007, Italian investigators reported that 75% of the patients in their study who took peppermint oil capsules for four weeks had a major reduction in irritable bowel syndrome (IBS) symptoms, compared with just 38% of those who took a placebo.^[19] A second study in 2010, conducted in Iran, found similar results.^[20] 2011 research showed that peppermint acts through a specific anti-pain channel called TRPM8 to reduce pain sensing fibres. The authors feel that this study provides information that is potentially the first step in determining a new type of mainstream clinical treatment for Irritable Bowel Syndrome.^[21]

 

Similarly, some poorly designed earlier trials found that peppermint oil has the ability to reduce colicky abdominal pain due to IBS with an NNT (number needed to treat) around 3.1,^[22] but the oil is an irritant to the stomach in the quantity required and therefore needs wrapping for delayed release in the intestine. This could also be achieved by using the whole herb or leaves rather than the volatile components alone. Peppermint relaxes the gastro-esophageal sphincter, thus promoting belching.^{[citation needed]}

 

Peppermint oil is also used in some Chinese medicines / medicated oils.