Marshmallow root (Althaea officinalis) has a long history of use for dry coughs, sore or irritated throats, stomach ulcers and digestive discomfort, and even used traditionally topically as well. One of the main benefits that have been found in human studies is the ability to soothe and coat irritated mucous membranes, this is one reason why its helpful with coughs and digestive issues. There are a few herbs that I feel like are understudied, and although marshmallow root does have a lot of stud