The Olympian made the announcement on 2DayFM on Thursday, saying the reaction to her performance at Paris 2024 led to her decision.
"I still break, but I don't compete. I'm not going to compete any more. No. No," Gunn said.
"I was going to keep competing, for sure, but that seems really difficult for me to do now to approach a battle.
"It's been really upsetting. I just didn't have any control over how people saw me or who I was," Gunn said.
"Dancing is so much fun, and it makes you feel good. I don't think people should feel crap about the way that they dance.
"If you get out there, and you have fun on the dance floor, then just own it."