Mint has been traditionally used in India, Europe and the middle East as a remedy for stomach upset. It has been known to help with symptoms of irritable bowel syndrome. Its perillyl alchohol, has been shown in animal studies to slow down the growth of certain types of cancer. Mint has antifungal properties and may be taken as a supplement, prepared as a tea, or included in many food dishes.
The substance called menthol has anesthetic properties and it's calming the gastric mucous membrane. The mint contains isovaleriane, that it is also known for it's calming properties.
Menthol acts like a vasodilatator so it becomes very useful in treating sinusitis. Menthol's calming properties make it a recommended antispasmodic in cases of asthma.
Though, the mint oil is not recommended to pregnant women or breast feeding women.