The 20 percent of Americans who suffer from painful canker sores may find relief in a surprising source: licorice—but that’s licorice root extract, not Twizzlers. Researchers from the University of Washington in Seattle applied an adhesive patch infused with licorice root extract over the canker sores of one group of study participants, applied a placebo patch to a second group and gave no treatment to a third. After four days, 81 percent of the licorice group reported no pain, compared to 63 percent of those who received the placebo and 40 percent of those who received no treatment. Also, the patches reduced canker-sore size by 90 percent, compared to a 68 percent reduction for those given the placebo and a 13 percent increase in size for those who used no patch. The extract-infused patches, called CankerMelts, can be found at drugstores nationwide or drugstore.com.