Althaea officinalis (Marshmallow, Marsh Mallow, or Common Marshmallow) is a species native to Africa, which is used as a medicinal plant and ornamental plant.
The stems, which die down in the autumn, are erect, 3 to 4 feet (1.2 m) high, simple, or putting out only a few lateral branches. The leaves, shortly petioled, are roundish, ovate-cordate, 2 to 3 inches (76 mm) long, and about 1 1/4 inch broad, entire or three to five lobed, irregularly toothed at the margin, and thick. They are soft and velvety on both sides, due to a dense covering of stellate hairs. The flowers are shaped like those of the common Mallow, but are smaller and of a pale colour.
The common Mallow is frequently called by country people, 'Marsh Mallow,' but the true Marsh Mallow is distinguished from all the other Mallows growing in Great Britain, by the numerous divisions of the outer calyx (six to nine cleft), by the hoary down which thickly clothes the stems, and foliage, and by the numerous panicles of blush-coloured flowers, paler than the Common Mallow. The roots are perennial, thick, long and tapering, very tough and pliant, whitish yellow outside, white and fibrous within. The whole plant, particularly the root, abounds with a mild mucilage, which is emollient to a much greater degree than the common Mallow. The generic name, Althaea, is derived from the Greek, altho (to cure), from its healing properties. The name of the order, Malvaceae, is derived from the Greek, malake (soft), from the special qualities of the Mallows in softening and healing.
Most of the Mallows have been used as food, and are mentioned by early classic writers with this connection. Mallow was an esculent vegetable among the Romans; a dish of Marsh Mallow was one of their delicacies. The Chinese use some sort of Mallow in their food, and Prosper Alpinus stated in 1592 that a plant of the Mallow kind was eaten by the Egyptians. Many of the poorer inhabitants of Syria - especially the Fellahs, Greeks and Armenians - subsist for weeks on herbs, of which Marsh Mallow is one of the most common. When boiled first and fried with onions and butter, the roots are said to form a palatable dish, and in times of scarcity consequent upon the failure of the crops, this plant, which fortunately grows there in great abundance, is much collected for food.
The leaves, flowers and the root of A. officinalis (marshmallow) all have medicinal properties. The leaves, which are collected in summer as the plant begins to flower, have demulcent, expectorant, diuretic, and emollient properties. It is generally used in ailments of the lungs and the urinary systems, specifically in urethritis and kidney stones. The root, which is harvested in late autumn, has demulcent, diuretic, emollient, and vulnerary properties. It is generally used for digestive and skin problems, specifically inflammations of the mouth, gastritis, peptic ulcer, enteritis, and colitis (Medline.com). It increases the flow of breast milk and soothes the bronchial tubes. It has been used to treat constipation as well as irritable bowel syndrome. Externally the root is used in treating varicose veins, ulcers, abscesses, and boils. The root extract (halawa extract) is sometimes used as flavouring in the making of a middle eastern snack called halva.