Health Benefits of Licorice Root

Age-old ulcer remedy may be risky if overused

licorice root
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The root of the licorice plant (Glycyrrhiza glabra or Glycyrrhiza uralensis) has a long history of use in Eastern and Western medicine. The licorice plant is a perennial legume native to the Middle East and parts of Asia and India.

Traditional practitioners believe that licorice root can treat a number of health conditions, including bronchitis, constipation, heartburn, gastric ulcer, eczema, and menstrual cramps. Although licorice is generally safe to use, the overconsumption can lead to severe side effects and even poisoning.

In traditional Chinese medicine, licorice root is referred to as gan zao. In Ayurvedic medicine, it is called either mulethi or its Sanskrit name yashtimadhu.

Health Benefits

Although the research is limited, studies suggest that licorice may offer certain health benefits, primarily related to the digestive tract. Many of the benefits are attributed to a substance in licorice root known as glycyrrhizinic acid, which is believed to have antiulcer, anti-inflammatory, antimicrobial, and antispasmodic effects.

Canker Sores

In a 2008 study, scientists found that an adhesive patch infused with licorice root accelerated the healing of recurrent aphthous ulcers (also known as canker sores). After seven days of treatment, people provided the patch had a significant decrease in ulcer size. By contrast, those offered no treatment saw their ulcer size increase by 13 percent.

Chronic Bronchitis

There is some evidence that licorice root may slow the progression of chronic bronchitis associated in people with chronic obstructive pulmonary disease (COPD).

According to test tube studies conducted at Chung Shan Medical University in Taiwan, the glycyrrhizic, asiatic, and oleanolic acids found in licorice root have an antioxidant effect that is protective of the cells in the bronchi in the lungs.

This suggests that licorice may help slow (rather than stop or reverse) the progression of COPD when used with standard medical treatments. Further human research would be needed to support these results.

Colorectal Cancer

Some scientists believe that the antioxidative properties of licorice may help reduce the risk of certain cancers, most predominately colorectal cancer. While the bulk of research has been limited to the animal or test tube studies, some of it has been promising.

A preliminary study from Vanderbilt University Medical Center reported that glycyrrhizic acid found in licorice inhibited the cyclooxygenase 2 (COX-2) enzyme, which promotes the development of colorectal cancer.

According to the research, inhibiting the COX-2 enzyme translated to a reduction in the number colorectal polyps (adenomas) and tumors in test mice. Future research may help determine whether the same effect might be seen in humans.

Functional Dyspepsia

When used in combination with other herbs, licorice root may help ease the pain of functional dyspepsia (FD), a chronic disorder marked by upper abdominal discomfort.

In a 2004 study involving 120 people with FD, a herbal remedy comprised of licorice root, bitter candytuft, matricaria flower, peppermint, and caraway was explored as a possible remedy.

According to the research, 43.3 percent of the participants provided the licorice-based remedy experienced a complete resolution of symptoms after eight weeks compared to just 3.3 percent of the placebo group.

Menopause and Menstrual Symptoms

Licorice root is a mainstay home remedy for women with menstrual cramps and is also believed to help alleviate many of the adverse symptoms of menopause, including hot flashes.

Licorice contains phytoestrogens, plant-based compounds that mimic the effects of estrogen in the body. Despite evidence of their benefits, it is still unclear how well the phytoestrogens in licorice root work, if at all.

A 2012 study involving 120 women with hot flashes reported that a daily, 330-milligram dose of licorice root provided only modest relief in the frequency and severity of hot flashes compared to the placebo group.

Once the treatment was stopped, both groups experienced a rebound of menopausal symptoms.

Peptic Ulcers

Licorice's role in treating peptic ulcer disease has gained increasing interest in the scientific community, specifically in regards to its effect on a bacteria known as Helicobacter pylori (H. pylori). H. pylori is the primary cause of peptic ulcers and one of the most notoriously difficult infections to eradicate.

A 2016 study in the Brazilian Journal of Infectious Diseases reported that licorice root added to standard triple antibiotic therapy increased H. pylori eradication rates from 62.5 percent in the placebo group to 83.3 percent in the licorice group.

Licorice root also appears to exert antimicrobial properties that may also treat certain fungal infections (like Candida albicans) and other hard-to-treat bacterial infections (like Staphylococcus aureus, Bacillus subtilis, and Enterococcus faecalis).

Possible Side Effects

When taken as a supplement or tea, licorice root is considered safe and well tolerated in adults. Some people may experience mild side effects, including upset stomach, bloating, and heartburn. These commonly occur if you exceed the recommended dose.

Licorice root supplements are only intended for short-term use. Consuming licorice daily for several weeks or longer can cause severe and potentially life-threatening side effects.

Many of these side effects are the result of the excessive accumulation of glycyrrhizinic acid, which triggers an abnormal increase in the stress hormone cortisol. This can lead to a severe imbalance in the body's fluids and electrolytes, manifesting with an array of possible symptoms, including:

  • Fatigue
  • Headache
  • Fluid retention and swelling (edema)
  • High blood pressure
  • Muscle weakness or cramping
  • Nausea and vomiting
  • Abnormal tingling or burning sensations
  • Low sex drive
  • Erectile dysfunction
  • Missed or irregular periods

Extreme cases can lead to licorice poisoning and the development of kidney failure, paralysis, congestive heart failure, pulmonary edema, and brain damage.

Due to the lack of research, licorice root should not be used in children, pregnant women, or nursing mothers. Licorice should also be avoided in people with kidney or liver dysfunction.

Drug Interactions

Licorice can interact with a number of medications, either by reducing their efficacy (and making them less potent) or increasing their efficacy (and worsening their side effects). These include:

  • Anti-arrhythmia drugs like Lanoxin (digoxin)
  • Anticholesterol drugs like Lescol (fluvastatin)
  • Antihypertensive drugs like Cozaar (losartan)
  • Anticoagulants ("blood thinners") like Coumadin (warfarin)
  • Diuretics ("water pills") like Lasix (furosemide)
  • Estrogen-based contraceptives
  • Nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen), Celebrex (celecoxib), and Voltaren (diclofenac)

To avoid interactions, advise your doctor if you are taking licorice root or any other natural or herbal supplement.

Dosage and Preparation

Licorice root products (including chewable tablets, capsules, extracts, teas, lozenges, tinctures, and powders) are available in most health food stores. While there are no universal guidelines directing the appropriate use of licorice root, doses of up to 400 milligrams twice daily are considered safe for short-term use.

Look for formulations that contain no more than 10% glycyrrhizin. As a general rule, you should never exceed the recommended dosage on the product label or take a licorice supplement for longer than three to six weeks

In additiion to dietary supplements, dried licorice root can be purchased online or through a traditional Chinese medicine distributor. Whole licorice root is difficult to use given that you are less able to control the dose. Shaved root, by contrast, can easily be made into tea by steeping a tablespoon of the shavings in a cup of boiling water.

Licorice teabags can be also found at most groceries store, some of which are mixed with black, green, or rooibos tea.

For best results, speak with your doctor before using any licorice root product, especially if you have a health condition.

What to Look For

Licorice root is classified as a dietary supplement by the U.S. Food and Drug Administration (FDA). As such, it is not required to undergo the rigorous testing that pharmaceutical drugs do and can vary in quality from one brand to the next.

To ensure the utmost quality and safety, only purchased brands certified by an independent body such as the U.S. Pharmacopeia (USP), ConsumerLab, or NSF International.

Moreover, only purchase supplements that specify the amount of glycyrrhizin on the product. If buying dried licorice root, choose those that have been certified organic whenever possible.

Other Quesions

Can you get sick eating licorice candy?

Binging on licorice candy occasionally will likely cause you nothing more than an upset stomach and heartburn. The same may not be true if you consume licorice habitually.

In 2017, the FDA issued an advisement, warning consumers that adults over 40 who eat 2 ounces of natural black licorice per day for at least two weeks could end up in the hospital with cardiac arrhythmia and other serious symptoms.

As a rule, keep your consumption of licorice candy to a minimum. If you eat large amounts and start to feel your heart beating wildly or your muscles going weak, call your doctor immediately.

With that being said, not all licorice candy is made with licorice. Many modern brands are "licorice-flavored" and are made with anise-based flavorings that do not contain any glycyrrhizin.

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