Licorice - Glycyrrhiza glabra

Detailed Description

Licorice—sometimes referred to as sweet root—is a versatile plant prized for components that are up to 50 times sweeter than beet sugar.

Botanical Information

Licorice is a perennial plant, typically reaching up to 1.5 meters in height. It features an upright, sturdy stem and long, deep roots. Its flowers are arranged in clusters, each measuring about 0.8-1.2 cm, blooming with delicate purple blossoms at the start of summer. The fruit is a pod containing several seeds. Leaves are chiefly pinnate (with 9–17 leaflets), each leaflet being lanceolate to ovate and measuring 7–15 cm in length.

Origin and Distribution

Licorice originates from the Mediterranean and certain parts of Asia. It shares botanical similarities with anise and fennel due to their comparable active constituents. The English name 'licorice' comes from Middle English via Old French 'licoresse,' derived from the Greek 'glykyrrhiza' meaning 'sweet root,' as described by the ancient physician Dioscorides.

Licorice was likely introduced to Central Europe by Benedictine monks, who began cultivating it purposefully in the 16th century. Wild varieties of Glycyrrhiza glabra can still be found in southern Moravia. Today, licorice is widespread across southern Europe and parts of Asia, with less prevalence in the Americas and Australia. In these regions, roots from several licorice species are vital herbal remedies in both traditional and official medicine. Licorice cultivation in the Czech lands began in the 16th century, and was most extensive in southern Moravia near Mikulov and Hustopeče by the 19th century. Naturalized plants are still spotted along the region's steppic slopes and vineyard margins.

Usage / Dosage

Licorice is recognized as one of the oldest medicinal herbal remedies in the world, with mentions in Egyptian papyri as a treatment for respiratory catarrh centuries before our era. The root has been essential in both folk and modern medicine. In ancient Egypt, it was used for medicinal purposes, while in India, it was traditionally combined with boiled milk, nut grass, and pepper for addressing symptoms such as frigidity. Mattioli’s herbals describe its cultivation, harvesting, and preparation for medicinal formulas in medieval Europe. In the Czech tradition, licorice decoctions became popular for soothing irritating coughs.

The most notable active compound in licorice is glycyrrhizic acid (up to 15% content), which makes licorice one of the strongest natural remedies for peptic ulcers. Licorice also provides flavonoid acids such as liquiritin and liquiritigenin. These support the production of gastric acids if deficient, or conversely protect against stomach and duodenal ulcers in the cases of overacidity (notably at higher doses, such as 20–60 g of extract dissolved in water per day).

Licorice acts as a mucolytic, helping to dissolve thick phlegm in the airways and facilitating its removal from mucous membranes, which is why it forms the base of many modern cough syrups. It’s also used in conventional and natural medicine for mouth ulcer care. The primary active ingredient, glycyrrhizin, stimulates the stomach lining to increase secretion in the airways, while also supporting the ciliary movement in the bronchial passages, making it valuable for easing irritating or asthmatic coughs and bronchitis.

Locally, licorice can serve as a topical antiviral remedy, especially for herpes infections. Derivatives of glycyrrhizic acid are popular in Japan for treating and preventing chronic viral hepatitis, thanks to their antibiotic, antiviral, and anti-inflammatory benefits. Glycyrrhizic and glycyrrhetinic acids affect steroid hormone actions, and the plant contains isoflavones (phytoestrogens) that balance hormonal cycles and support women’s health, including ovarian hormone production and menopause support. Licorice also increases blood pressure when needed, and so it’s not suitable for people with hypertension. Isoflavones further assist inhibiting bacterial activity and enhancing female hormone synthesis and have shown to reduce blood platelet aggregation (blood thinning) in laboratory conditions.

Other Uses
A significant share of licorice production is used as a sweetener and flavoring agent in tobacco products. The root’s aroma and taste give tobacco a sweet woody undertone and can help open airways, making smoke easier to inhale.

Alternative Medicine
In traditional Chinese medicine, licorice is included in herbal blends to harmonize and stabilize formula composition. In Ayurveda, licorice (known as Yashtimadhu in Sanskrit and mulethi in Hindi) is commonly used to treat respiratory and digestive ailments, notably ulcers, hyperacidity, and bronchial conditions. Mulethi is also considered anabolic and anti-stress in these systems.

Toxicity
Excessive consumption of licorice (over 50 grams per day for two weeks) is rarely associated with toxic liver load, cardiovascular troubles, or elevated blood pressure.

Pregnancy
Research on licorice compounds and their association with premature births suggests that extremely high intakes (about 500 mg pure glycyrrhizin) would be required to induce dehydration and consequently preterm labor. Consumption of licorice tea blends or sweets in typical quantities poses negligible risk. However, because licorice raises blood pressure, it’s not recommended for children, pregnant women, or those with hypertension or cardiovascular conditions.

Active Compounds

The root—the medicinal part of the plant—contains starch, bitters, saponins (especially glycyrrhizin, which is about 30–50 times sweeter than sucrose), as well as mono- and oligosaccharides. Other significant components include glycosides (particularly liquiritin and liquiritigenin), coumarin derivatives, smaller amounts of phytoestrogens, vitamin E, B-complex vitamins, manganese, iodine, zinc, and phosphorus.

Traditional Dosage

Licorice roots are harvested in autumn and dried at approximately 30°C. The dried root has a distinct aroma and a mildly pungent flavor. An extract is made by chopping and grinding the root, then boiling until it takes on a black color and desired consistency—this product is known as 'licorice stick' or 'block.'

Herbal Tea for Ulcers

Combine equal parts of marshmallow root, fennel fruit, licorice root, and chamomile flowers to obtain 50–100 g of the blend. Steep 2 teaspoons in about 200 ml of water, simmer, and infuse (both for around 20 minutes), then sip before bedtime.

Cough Syrup

Mix about 25 g licorice root, 100 g raisins, and a teaspoon of flax or pine seeds in ½ liter water. Simmer until the volume doubles. Add about 60 g sugar and stir until dissolved (optionally add ½ tablespoon vinegar). Strain, store cool, or drink warm—ideally before bedtime.

Expectorant Tea

Prepare a mixture of equal weights licorice, valerian, raisins, and anise (or licorice may be used with valerian or anise—these are not fully equivalent). Boil the mixture and sweeten with honey. Drink in the morning and afternoon.

Mouthwash for Sores and Inflammation

Steep about 30 g licorice root (optionally with chamomile flowers) in ½ liter cold water, bring to a slow boil, and simmer for 15 minutes. Use as a rinse or drink to treat mouth ulcers and oral inflammations.

Tincture for Ulcers

Macerate licorice root in 60% ethanol at a 5:1 weight ratio. After straining, apply topically or take internally—2–5 ml up to 3 times daily mixed in water, juice, or soft foods.

Licorice Block

After harvest, clean, slice, and grind the root. Boil with water until it thickens and darkens. Pour hot mass into containers to cool and solidify—resulting in a brittle, sweet-tasting licorice block. For further use, dilute with hot water to achieve a pliable, chewy texture, commonly available as a sweet shop candy.

Caution on Overdose: While some literature highlights serious risks of licorice overconsumption, adverse effects are linked to excessive doses (e.g., daily intake of 500 g for over a week, or chronic consumption of large quantities of real licorice candies). Overdose may cause hypertension, digestive problems, stomach cramps, or headaches. However, sensible everyday quantities are not harmful.