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by Dr Iona McCleery

Glycyrrhiza glabra Liquoricebottle of essence and dried woody roots (image: Efraim Lev and Zohar Amar, Wellcome Images)

Liquorice: a little history of the 'sweet root'

Liquorice is one of the sweetest naturally-occurring substances (fifty times sweeter than cane sugar) and has been used for centuries in medicines and to quench thirst. It was known to the Ancient Greeks but may originally be from Mongolia or China. The name ‘liquorice’ comes from glycyrrhiza, Greek for ‘sweet root’.

Codex Julianae Aniciae (Facsimile), image courtesy of the Wellcome Library, LondonThere is no documented evidence that liquorice was grown in England before 1579. However, it is possible that medieval monks may have grown it in the gardens of monasteries, such as those founded in Pontefract. One of the most important growing areas in the town became the area of Monkhill.

Liquorice is a difficult plant to grow in England, flourishing in very few places. It requires deep, rich soil without much clay and needs intensive care. Unlike in the Mediterranean where it behaves like a weed, it rarely spreads naturally in England and must be grown from ‘sets’ (bud cuttings).

A visitor to Pontefract in 1697 wrote:
…it is a fruitful place, fine flowers and trees, with all sorts of fruit, but that which is mostly intended is the increasing of liquorice, which the gardens are filled with, and anybody that has but a little ground improves it for the produce of liquorice ... and it returns several 100 pounds yearly to the town.

In 1701, the Mayor of Pontefract banned the selling of liquorice buds or ‘sets’ outside the borough in order to create a monopoly over the plant. Several local families such as the Dunhills came to dominate trade in liquorice during the 18th century.

Liquorice was used mostly for medicines until the 19th century. The Pontefract cake, developed by George Dunhill in 1760, was intended as a medicinal pastille to be dissolved in water.

Glycyrrhiza glabra Liquoricebottle of essence and dried woody roots (image: Efraim Lev and Zohar Amar, Wellcome Images) Known also as horseheal and scabwort, liquorice was used to treat wounds, asthma, coughs, eczema and urinary problems and to sweeten medicines and the breath. It is still used today in herbal medicines, cough mixtures and as a flavouring, e.g. in alcoholic drinks such as pernod and gin, and in chewing tobacco.

By the 1890s, liquorice was associated with confectionary rather than medicine. Demand had outstripped supply meaning that local firms imported bulk quantities from Turkey. The cheaper price of sugar meant that liquorice was no longer needed as a sweetener. There was no longer any profit in growing liquorice locally; the last commercial crop in Pontefract was in 1966.

The most powerful component of liquorice is glycyrrhizin, first identified in 1907. It was once used as a safe sweetener for diabetics, and is still found in some sugar-free chewing gums. Various liquorice compounds have been investigated for treating peptic ulcers, hepatitis B and malaria.

In large quantities liquorice can be poisonous. People who frequently take herbal medicines containing liquorice and/or regularly eat lots of liquorice sweets per day (more than 5g) may develop a serious metabolic disorder, especially if they already have heart problems. Symptoms include high blood pressure, numbness and muscle weakness.

As with many things, liquorice is great but enjoy it in moderation!


J. A Chartres, ‘A special crop and its markets in the eighteenth century: the case of Pontefract liquorice’, in: R. W. Hoyle (ed.), People, Landscape and Alternative Agriculture: Essays for Joan Thirsk (Exeter, 2004), 114-32
C. Fiore, M. Eisenhut, E. Ragazzi, G. Sanchin and D. Armanini, ‘A history of the therapeutic use of liquorice in Europe’, Journal of Ethnopharmacology 99 (2005), 317-24
A. Olukoga and D. Donaldson, ‘Historical perspectives on health: the history of liquorice: the plant, its extract, cultivation, commercialisation and etymology’, The Journal of the Royal Society for the Promotion of Health 118 (1998), 300-304
A. Olukoga and D. Donaldson, ‘Liquorice and its health implications’, The Journal of the Royal Society for the Promotion of Health 120 (2000), 83-89