There are certain stubborn pockets of fat that don’t respond well to diet and exercise. And by don’t respond well, we mean they remain thoroughly unchanged regardless of the calories you cut and the hours to log at the gym. One area in particular comes to mind, and that’s the spot directly underneath the chin—an area so lovingly dubbed the double chin. Up until yesterday, the only effective solutions for eliminating double chins were surgery or liposuction. Then along came Kybella, an injectable substance that destroys fat cells under the chin.