Tasty Treat Becomes a Black Trick on All Saints Day: Don't Overindulge on Licorice! - Page 2
According to the FDA, eating 2 ounces of black licorice a day for two weeks could land someone in the hospital with a heart arrhythmia because of dropped potassium levels. The good news is that once the licorice is out of the system, the potassium levels return to normal. So if you are going to eat licorice, keep in mind that you also need to eat potassium rich foods that day, like a banana, or stay within the two ounce limit of licorice.
But it's the people with high blood pressure, heart disease or kidney disease who need to take the FDA's Halloween alert to heart. They are susceptible to black licorice’s effects, according to the National Institutes of Health. For them as few as 5 grams (.18 ounces) per day could cause health problems.
If one has heart disease, it's probably wise to stay away from licorice and if one must have candy, perhaps try dark chocolate which studies have shown to have health benefits. Or if one can help it, stay away from candy altogether. The sugar will get you if the other stuff won't!