While true licorice (and I use that term because many products, including candy, that have "licorice" on the label actually use other ingredients) does have proven health benefits, it can also have dangerous side effects.
The benefits include: soothing a sore throat and upper respiratory infection (because licorice is considered a mild anti-inflammatory), soothing stomach ulcers and lowering cholesterol.
Potential side effects, however, include: causing or increasing high blood pressure, signs of congestive heart failure (retaining water with swelling hands and feet, difficulty breathing), severe muscle pain, low blood potassium and irregular heart rhythm. All of these can be life-threatening.
It seems to me that the risks are severe enough to outweigh any possible health benefits, so I stay away from licorice!