"I Don't Brush My Teeth!"

Wonder how Jessica Simpson maintains her million-dollar smile?

So does she. "I don't brush my teeth," she told iheartradio Thursday. "No, really!".

"I just use Listerine -- and sometimes I'll use my sweater," she claimed, bursting into laughter.

"I do brush every now and again, but my teeth are extremely powerful. Fine, maybe when I'm 60 I'll all, "ow!"The singer adds that she loves "anything fried," and that her nutrition habits weren't always the best. "Growing up in Texas for me, fish was a fish stick. We weren't really the healthiest of people. [My mom] didn't force me to eat healthy."

Simpson, 29, opened up yet again about her ex John Mayer's raunchy comments regarding their sex life. "Maybe in his mind he was thinking about giving me a compliment but he wasn’t," she quipped.