The Food & Drug Administration (FDA) is preaching moderation when it comes to eating black licorice this Halloween.
FDA experts say it contains the compound glycyrrhizin. It's a sweetening compound derived from the licorice root.
The compound can cause potassium levels in the body to decrease.
When that happens, some people experience abnormal heart rhythms, while others may see their blood pressure rise, become lethargic, or suffer congestive heart failure.
"If you already have heart disease or high blood pressure then you should be a little more cognizant of how you're feeling if you're eating this kind of licorice and stop eating it if you think you notice any type of irregular heartbeats," says Dietitian Kate Patton with the Cleveland Clinic.
Researchers say limit your black licorice consumption to less than two ounces a day, for at least two weeks.
Patton says if you feel funny after eating black licorice, make sure you call your doctor.
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