"An ingredient to look for in lip hydration to lead to plumper lips is hyaluronic acid. This ingredient works by drawing more moisture into the lips," Fenton says. To stimulate collagen in the lips, look into an oligopeptide such as
palmitoyl oligopeptide (sometimes also called palmitoyl hexapeptide-12 or Pal-GHK). "These ingredients tend to provide a more subtle effect that takes some time to see results," he adds.