Peppermint is a herb traditionally used in cooking or as a digestive aid the essential oil is produced from the plants leaves stems and shoots holland and barretts peppermint capsules are enteric coated capsules forming a protective barrier to allow the oil to be absorbed providing the best benefits peppermint is a herb traditionally used in cooking or as a digestive aid the essential oil is produced from the plants leaves stems and shoots holland and barretts peppermint capsules are