One of the most popular herbs used throughout the world, peppermint has a long history of being beneficial for the body. Peppermint can be used to ease upper respiratory infections. More well known is peppermint's effect on stomach issues. Popular medicine has used peppermint to ail stomach aches and digestive problems, and peppermint oil has been demonstrated to have a positive effect on those with IBS in a double blind placebo-controlled randomized trial.