Black licorice: Eating too much can cause abnormal heart rhythms


Black licorice candy is an old-fashioned favorite. But eating too much of it can cause health problems. So, the US Food and Drug Administration (FDA) recommends snacking on this treat in moderation.

The sweetening compound, glycyrrhizin, is derived from licorice root. This compound can cause potassium levels in the body to fall. It can result in abnormal heart rhythms, high blood pressure, swelling (edema), weakness (lethargy), and heart failure. People who are over 40, or have a history of heart disease or high blood pressure, seem to be more at risk. So, if you eat 2 ounces of black licorice a day for at least 2 weeks, you may develop an irregular heart rhythm or arrhythmia. Once you stop eating black licorice, potassium levels usually go back to normal and there are no permanent health problems.

The National Institutes of Health (NIH) says licorice root has a long history of use as a folk or traditional remedy in many cultures. It has been used to treat various ailments such as heartburn, sore throat, cough, and some infections. However, there are insufficient data to prove it is effective in treating any medical condition.

Licorice is also used as a flavoring in some food products. However, products manufactured in the US do not use licorice as flavoring. Anise oil, which has the same smell and taste, is used instead. Also, the dietary supplement licorice root can be found with the glycyrrhizin compound removed.

Here’s what you can do: If you like black licorice, do not eat large amounts at one time, no matter what your age. If you have been eating black licorice and have an irregular heart rhythm, high blood pressure, weakness, or swelling, stop eating the licorice. Contact your doctor or nurse and discuss the situation. Black licorice can also interact with some medicines, herbs, and dietary supplements. It is always important to talk to your doctor, nurse, or pharmacist about all your medicines, both prescription and over-the-counter. Ask questions if there is a possible interaction with the medicine or supplements you take.

Advice from FDA is a feature brought to you by the US Food and Drug Administration (FDA). You can find this article and more on FDA’s Consumer Health Information website here. This website features the latest updates on medicines and products regulated by the FDA. Sign up for a free email subscription here.

Created on December 15, 2017

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