Licorice Root
Licorice root, considered one of the world's oldest herbal remedies, is derived from the root of the licorice plant (Glycyrrhiza glabra) .
Native to western Asia and southern Europe, licorice has long been used to treat various ailments and flavor candies, drinks and medicines .
Despite this history, only some of its uses are supported by scientific research. In addition, licorice can pose several health risks.
How is licorice root used?
The medicinal use of licorice dates back to ancient Egypt, where the root was made into a sweet drink for the pharaohs.
It has also been used in traditional Chinese, Middle Eastern and Greek medicines to soothe stomach aches, reduce inflammation and treat upper respiratory problems.
Contemporary uses
Today, many people use licorice root to treat ailments such as heartburn, acid reflux, flushing, coughing, and bacterial and viral infections. It is regularly available as a capsule or liquid supplement.Also, licorice tea is said to soothe sore throats, while topical gels are said to treat skin conditions such as acne or eczema.
In addition, licorice is used to flavor certain foods and drinks.
Surprisingly, many licorice candies are not flavored with licorice root but with anise oil, an essential oil from the anise plant (Pimpinella anisum) that has a similar flavor.
Plant compounds in licorice root
Although it contains hundreds of plant compounds, the main active compound in licorice root is glycyrrhizin
Glycyrrhizin is responsible for the sweet taste of the root, as well as its antioxidant, anti-inflammatory, and antimicrobial properties (1 Trusted Source, 3 Trusted Source, 6 Trusted Source).
However, glycyrrhizin is also linked to many of the negative effects of licorice root. As a result, some products use deglycyrrhizinated licorice (DGL), from which the glycyrrhizin has been removed.
Potential benefits of licorice
Current research shows promise for many of the beneficial uses of licorice root.
May help skin conditions
Licorice root contains over 300 compounds, some of which demonstrate powerful anti-inflammatory, antibacterial, and antiviral effects.
In particular, animal and test tube studies link glycyrrhizin to anti-inflammatory and antimicrobial benefits.
As a result, licorice root extract is used to treat a variety of skin conditions, including acne and eczema.
In a 2-week study of 60 adults, application of a topical gel containing licorice root extract significantly improved eczema.
Although topical licorice gels have also been used to treat acne, research on its effectiveness is mixed and rather limited.
May reduce acid reflux and indigestion
Licorice root extract is often used to relieve symptoms of indigestion, such as acid reflux, stomach pain and heartburn.
In a 30-day study of 50 adults with indigestion, taking a 75 mg licorice capsule twice daily resulted in significant improvements in symptoms, compared to a placebo.Licorice root extract may also relieve symptoms of gastroesophageal reflux disease (GERD), including acid reflux and heartburn.
In an 8-week study of 58 adults with GERD, a low dose of glycyrrhetinic acid in combination with standard treatment resulted in significant improvements in symptoms.
Another study of 58 adults with GERD noted that daily use of licorice root was more effective in reducing symptoms over a 2-year period than commonly used antacids.
Although these results are promising, larger human studies are needed.
May help treat peptic ulcers
Peptic ulcers are painful sores that develop in the stomach, lower esophagus, or small intestine. They are commonly caused by inflammation resulting from H. pylori bacteria.
Licorice root extract and its glycyrrhizin can help treat peptic ulcers.
A study in mice found that doses of licorice extract of 91 mg per pound (200 mg per kg) of body weight protected against these ulcers better than omeprazole, a common peptic ulcer drug.
Although more research is needed in humans, a 2-week study of 120 adults showed that consuming licorice extract in addition to standard treatment significantly reduced the presence of H. pylori (15 Trusted Source).
May have anti-cancer properties
Due to its content of numerous plant compounds with antioxidant and anti-inflammatory effects, licorice root extract has been studied for its protective effects against certain types of cancer.
In particular, liquorice extract and its compounds have been linked to slowing or preventing cell growth in tumours.
cell growth in skin, breast, colorectal and prostate cancers.
Because research is limited to test tubes and animals, its effects on human cancers are unknown.
However, licorice root extract may help treat oral mucositis - very painful mouth ulcers that people with cancer sometimes experience as a side effect of chemotherapy and radiation.
A 2-week study of 60 adults with head and neck cancer found that a topical licorice film was just as effective as standard treatment for oral mucositis.
May relieve upper respiratory conditions
Because of their anti-inflammatory and antimicrobial effects, both licorice root extract and tea can help upper respiratory tract conditions.
In particular, animal studies conclude that glycyrrhizin extract from licorice root helps relieve asthma, especially when added to modern asthma treatments.
While limited human research shows similar results, more rigorous, long-term studies are needed.
In addition, limited test tube and human studies suggest that tea and licorice root extract may protect against strep and prevent sore throats after surgery.
However, more research is needed.
May protect against tooth decay
Licorice root may help protect against bacteria that can lead to tooth decay.
A 3-week study provided 66 preschoolers with sugar-free lollipops containing 15 mg of licorice root twice a day during the school week. Consumption of lollipops significantly reduced the number of Streptococcus mutans bacteria, which are the main cause of tooth decay.
Test tube studies also show that licorice root extract is effective in protecting against bacteria commonly linked to tooth decay and cavities.
However, more research is needed on the optimal dose and form of licorice root.
Potential side effects and precautions
The Food and Drug Administration (FDA) has deemed licorice root to be generally recognized as safe for use in foods.
However, the FDA does not currently evaluate or test supplements for purity, efficacy, or accuracy of ingredient labeling.
In addition, short-term use of licorice root supplements and teas is widely considered safe. However, high doses can produce adverse effects and individuals with certain health conditions may want to avoid it.
Licorice Root Overdose
Both chronic use and large doses of licorice root products can lead to the accumulation of glycyrrhizin in the body.
High levels of glycyrrhizin have been shown to cause an abnormal increase in the stress hormone cortisol, which can cause imbalances in fluid and electrolyte levels.
As a result, chronic, high doses of licorice root products can trigger several dangerous symptoms, including
- Low potassium levels
- High blood pressure
- muscle weakness
- Abnormal heart rhythms
Although rare, licorice poisoning can occur. It may cause renal failure, congestive heart failure or accumulation of excess fluid in the lungs.
Therefore, individuals with hypertension, congestive heart failure, kidney disease, or low potassium levels are encouraged to avoid licorice products containing glycyrrhizin altogether.
