What is marshmallow as a dietary supplement?

Overview

The similarity in name between the herb marshmallow and the sweet treat is more
than a coincidence, although the modern sugar-puff ball no longer bears much
relationship to the old-fashioned candy flavored with marshmallow herb.

Besides inspiring makers of campfire food, the marshmallow has also been used
medicinally since the time of ancient Greece. Hippocrates
spoke of it as a treatment for bruises and blood loss, and subsequent Roman
physicians recommended marshmallow for toothaches, insect bites, chilblains, and
irritated skin. In medieval Europe, herbalists used marshmallow to soothe
toothaches, coughs, sore throats, chapped skin, indigestion, and diarrhea.

Therapeutic Dosages

Marshmallow can be made into a soothing tea by steeping roots overnight in water and diluting to taste. This tea can be drunk as desired for symptomatic relief. Alternatively, one can take marshmallow in capsules (5 to 6 grams daily) or in tincture according to label directions. Marshmallow ointments can be applied directly to soothe inflamed or irritated skin.

Therapeutic Uses

Marshmallow contains large sugar molecules called mucilage, which are thought to
exert a soothing effect on mucous membranes; this is the basis of most proposed
uses of the herb. However, only double-blind, placebo-controlled
studies can prove a treatment effective, and no such studies
of marshmallow have been reported.

On the basis of its supposed soothing properties, tea or lozenges containing
marshmallow tea are often recommended for asthma, cough, colds, and sore throat.
Marshmallow taken as tea or in capsules is sometimes recommended for
Crohn’s
disease or ulcers, on the theory that mucilage
might sooth the lining of the digestive tract. Finally, marshmallow ointment is
sometimes recommended for irritated skin.

Safety Issues

Marshmallow is believed to be entirely safe. It is approved for use in foods, and its chemical makeup does not suggest any but benign effects. However, detailed safety studies have not been performed. One study suggests that marshmallow can slightly lower blood sugar levels. For this reason, people with diabetes should use caution when taking marshmallow. Safety in young children, pregnant or nursing women, and those with severe liver or kidney disease has not been established.

Bibliography

“Althaea officinalis, Marshmallow.” In The Western Herbal Tradition, by Graeme Tobyn, Alison Denham, and Margaret Whitelegg. New York: Churchill Livingstone/Elsevier, 2011.

Tomoda, M., et al. “Hypoglycemic Activity of Twenty Plant Mucilages and Three Modified Products.” Planta Medica 53 (1987): 8-12.