Licorice Root

Background

• Licorice root is cultivated throughout Europe, Asia, and the Middle East. It is used as a flavoring in candy, other foods, beverages, and tobacco products.
• Many “licorice” products sold in the United States do not contain actual licorice. Anise oil, which smells and tastes like licorice, is often used instead.
• 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.
• Today, licorice root is promoted as a dietary supplement for conditions such as digestive problems, menopausal symptoms, cough, and bacterial and viral infections. 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 (application to the skin).

How Much Do We Know?

• Some studies of licorice root in people have been completed, but there isn’t enough high-quality evidence to clearly support its use for any health condition.

What Have We Learned?

• Some products that contain licorice root and other ingredients may help relieve digestive symptoms. Because these are combination products, the role of licorice in their effects is uncertain.
• There’s some evidence that topical gels containing licorice root might be helpful for atopic dermatitis symptoms. Atopic dermatitis, also called eczema, is a chronic disease in which skin becomes irritated, inflamed, and itchy.
• A small number of studies suggest that using a licorice gargle or lozenges before surgery might help to prevent or lessen the severity of the sore throat that often occurs after surgery.

What Do We Know About Safety?

• Although licorice root is generally considered safe as a food ingredient, it can cause serious side effects, including increased blood pressure and decreased potassium levels, when consumed in large amounts or for long periods of time. Because the composition of licorice products varies, it isn’t possible to definitely say that a particular level of intake is safe or unsafe. The effects of licorice on potassium and blood pressure are a particular concern for people with hypertension (high blood pressure) or heart or kidney disease.
• Some side effects of licorice are believed to be caused by a component called glycyrrhizic acid. Licorice that has had this substance removed (called DGL for deglycyrrhizinated licorice) may not have the same degree of side effects.
• Heavy consumption of licorice during pregnancy has been associated with premature birth and health problems in the child. Little is known about whether it’s safe to use licorice root while breastfeeding.

Keep in Mind

• Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.

For More Information

• Using Dietary Supplements Wisely
• Know the Science: How Medications and Supplements Can Interact
• Know the Science: How To Make Sense of a Scientific Journal Article

Key References