Licorice root, which is considered one of the world’s oldest herbal remedies, comes from the root of the licorice plant (Glycyrrhiza glabra). Licorice root is cultivated throughout Europe, Asia, and the Middle East. It is used as a flavoring in candy and food, beverages, and tobacco products.
Licorice root has a long history of use going back to ancient Assyrian, Egyptian, Chinese, and Indian cultures. It was used traditionally for treating a variety of conditions, including lung, liver, circulatory, and kidney diseases.
Licorice gargles or lozenges have been used to try to prevent or reduce the sore throat that sometimes occurs after surgery. Licorice is also an ingredient in some products for topical use. Many people use licorice root to treat ailments like heartburn, acid reflux, hot flashes, coughs, and bacterial and viral infections. It’s regularly available as a capsule or liquid supplement. Licorice tea is said to soothe sore throats, while topical gels are claimed to treat skin conditions like acne or eczema.
Surprisingly, many licorice candies are flavored not with licorice root but with anise oil, an essential oil from the anise plant (Pimpinella anisum) that has a similar taste.
While it contains hundreds of plant compounds, licorice root’s primary active compound is glycyrrhizin. Glycyrrhizin is responsible for the root’s sweet taste, as well as its antioxidant, anti-inflammatory, and antimicrobial properties.
Glycyrrhizin is also linked to many of the adverse effects of licorice root. As a result, some products use deglycyrrhizinated licorice (DGL), which has had the glycyrrhizin removed.
In a 30-day study in 50 adults with indigestion, taking a 75-mg licorice capsule twice daily resulted in significant improvements in symptoms, compared with a placebo. Licorice root extract may also alleviate symptoms of gastroesophageal reflux disease (GERD), including acid reflux and heartburn.
In an 8-week study in 58 adults with GERD, a low dose of glycyrrhetinic acid in combination with standard treatment resulted in significant improvements in symptoms. Another study in 58 adults with GERD noted that the daily use of licorice root was more effective at reducing symptoms over a 2-year period than commonly used antacids.
A 2016 study of 120 people in Iran found that licorice root, added to standard triple antibiotic therapy, eliminated H. pylori 83.3% of the time. In a group that received antibiotic therapy plus placebo, treatment was successful in just 62.5% of cases.
Lab tests suggest that licorice root may offer benefits in treating some fungal infections, like Candida albicans, and other hard-to-treat bacterial infections like Staphylococcus aureus. Some past studies found that licorice root acted as an anti-inflammatory agent that speeds up the healing of canker sores.
Some scientists believe that the antioxidant effects of licorice may help to lower the risk of certain cancers, primarily colorectal cancer. While the bulk of research has been limited to animal or test-tube studies, some results have been promising. That includes a study in mice that found licorice root may offer possible benefits in preventing tumors related to colitis.
Due to its content of numerous plant compounds with antioxidant and anti-inflammatory effects, licorice root extract has been studied for its slowing or preventing cell growth in skin, breast, colorectal, and prostate cancers.
Licorice root extract may help treat very painful mouth sores that people with cancer sometimes experience as a side effect of chemotherapy and radiation.
Licorice root may help ease the pain of functional dyspepsia (FD). This is a disorder marked by bouts of upper abdominal discomfort. In one study, 50 people in India were given either a placebo or a product based on licorice root extract at a dose of 75 milligrams (mg) twice a day. The group who took the licorice reported greater relief of their symptoms than participants in the control group.
Licorice root has been studied in women with menstrual cramps due to its anti-inflammatory properties. It also is believed to help relieve many of the symptoms of menopause, including hot flashes. Licorice contains phytoestrogens. These are plant-based compounds that mimic the effects of estrogen in the body. In one case, a 2012 study looked at 90 women with hot flashes. Authors reported that a daily, 330-milligram dose of licorice root gave some modest relief, compared to a placebo. Once treatment stopped, the symptoms returned.
Licorice root may help protect against bacteria that can lead to cavities. A 3-week study gave 66 preschool-aged kids sugar-free lollipops containing 15 mg of licorice root twice per day during the school week. Consuming the lollipops significantly reduced the number of Streptococcus mutans bacteria, which are the main cause of cavities.
Licorice can interact with a number of drugs. Interactions include lowering the effectiveness or making the side effects worse. Check with you doctor if you are on any of the follow medications before you add licorice root to your diet:
- Heart arrhythmia drugs like Lanoxin (digoxin)
- High blood pressure drugs like Cozaar (losartan)
- Blood thinners like Coumadin (warfarin)
- Estrogen-based contraceptives
- Celebrex (celecoxib), and Voltaren (diclofenac)
- Cholesterol drugs like Lescol (fluvastatin)
- Nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen)
- Diuretics like Lasix (furosemide)
When taken as a supplement or tea, licorice root is considered safe. It is tolerated well in adults.
How to Buy
Licorice root products come in many forms available in most health food stores or online. These forms may include:
- Chewable tablets
There are no universal guidelines for the proper use of licorice root. Doses of 5 to 15 grams a day are considered safe for short-term use.
Licorice teabags can be found at many grocery stores. Some are mixed with black, green, or rooibos tea.
If you buy dried licorice root, choose a product that has been certified organic whenever possible. Licorice root is classified as a dietary supplement by the Food and Drug Administration (FDA). For this reason, licorice root products are not required to undergo the rigorous testing that pharmaceutical drugs do.
Only buy supplements that state the amount of glycyrrhizin on the product label. Look for licorice products that contain no more than 10% glycyrrhizin, or advertised as DGL (deglycyrrhizinated licorice). As a general rule, you should never exceed the recommended dosage on the product label. You also should not take licorice supplements for more than three to six weeks.
The quality can vary widely from one brand to the next. To ensure quality and safety, only buy brands that are certified by an independent body such as the U.S. Pharmacopeia (USP), ConsumerLab, or NSF International.
In addition to dietary supplements, dried licorice root can be found through a traditional Chinese medicine distributor. Whole licorice root is harder to use, given that you are less able to control the dose. It’s easy to make shaved root into tea – steep a tablespoon of the shavings in a cup of boiling water.
How to Store
Store supplements in a cool, dry place away from direct sunlight.
How to Cook
Hard and woody licorice roots impart the most flavor when steeped in hot liquid. Teas, syrups, sauces and custards can be infused by adding the root, heating, and then removing before serving. Increase the intensity of the flavour by adding more roots, or lengthening the amount of time that the roots are steeped in the liquid.
Licorice roots still give off strong aromas without needing to be heated. Like vanilla pods, they can be used to flavor sugar, and like dried juniper berries, they can be used to liven up salt cures.
Powdered licorice and licorice compound, can be added straight to recipes.