"I had the wisdom teeth taken out and then I had an overbite, so I had even more teeth that had to come out," she said. "I had … too many teeth and they're also big, so I could never really fully close my mouth when I was young, so I had two removed and then they pushed them back."
Klum's mum put the teeth in a pouch, which the model kept as a good-luck charm.
"When I was young and I was travelling everywhere and I was always by myself, because when you're a model you go from one job to the next so it's just your suitcase and your little handbag and that's it and then you hop around all on your own. For me, this was kind of like my good luck charm," she said. "I don't know why, it's just something that I did."
Klum doesn't carry the teeth with her any more, in fact she's not even sure where the pouch is these days.
"It was kind of a weird, random thing that I did," she told news.com.au. "I was young and did weird things like that, I guess."
Klum appeared on I've Got News For You to promote a song she's just released called Chai Tea with Heidi.
The track features Snoop Dogg and DJ duo Wedding Cake.
The song came about after the producers of Germany's Next Top Model suggested to Klum she record the theme song for the next season of the show.
"I was like, 'yes', that sounds like a whole lot of fun, I definitely want to do that!" Klum said about the idea. "And then I was like, I would love to do it with one of my most favourite artists, and that is Snoop Dogg."
Klum had met the rapper multiple times in the past, so she called him and pitched the idea.
“He immediately said yes,” Klum told news.com.au. “And he invited me to come to the studio here in Inglewood in Los Angeles and then we worked on the song together.”