The medicinal value of the plantains is attributed mainly to the mucilage that they contain. Mucilage is plant polysaccharide which easily absorbs water to form a gel. The gel is soothing to mucous membranes so that the leaves of both our native species, Plantago major (Greater plantain) and Plantago lanceolata (Ribwort), may be used in remedies for inflammation of the digestive tract. What is harder to explain is their apparent effectiveness in soothing sore throats and coughs, since the mucilage cannot be digested and absorbed. The effect is believed to be mediated by some sort of nervous reflex.

A tropical relative of our plantains is Plantago psyllium, from which we obtain psyllium (isphagula) husk. This contains large quantities of mucilage and is the basis of a popular over-the-counter remedy for digestive problems. It is mixed with cold water and left to swell before the mixture is drunk.

      Caroline Wheeler