(CNN) – If Halloween is your excuse for endlessly indulging in candy, go slow on the black licorice.
Just as it does each Halloween, the Food and Drug Administration has posted a reminder on its website urging folks to keep their black licorice consumption to a minimum.
The reasoning? Too much of the old-fashioned favorite can cause health problems such as irregular heart rhythm, especially in people over 40.
Black licorice contains a sweetening compound called glycyrrhizin, which can cause a drop in potassium levels. With low levels, some people might experience high blood pressure, swelling and even congestive heart failure, the FDA says.