The 'Juice' hitmaker spent years honing her craft and thinks that has helped her with her career now because her voice is so much more "finely tuned and shaped".
She told the new issue of Britain's Vogue magazine: "I became a good singer touring as a rapper.
"All of the things that I would rap would turn into melodies and they would get real soulful and real punchy.
"It was not a secret ace card in the pack, it was a tool that I was finely tuning and shaping."
The 31-year-old star claims her message of body positivity is to promote it to herself.
She explained: "Anybody that uses body positivity to sell something is using it for their personal gain. That's just it.
"We weren't selling anything in the beginning. We were just selling ourselves and selling ourselves on the idea - selling ourselves on ourselves, you know?
"I'm not trying to sell you me. I'm trying to sell you, you."
Lizzo is thankful she didn't find fame and success when she was much younger.
She explained: "I think if I was 21 right now, I would not be able to maintain this lifestyle without having major anxiety and panic attacks. But thank God, my journey is all about self-care and finding that love for yourself and nurturing yourself. Because that's what artists need more than anything."
The 'Truth Hurts' singer also spoke about her childhood, and said she didn't have anyone to look up to in the media that looked like her.
She said: "I would watch things on television and I would look at magazines and I would not see myself. When you don't see yourself, you start to think something's wrong with you. Then you want to look like those things and when you realise it's a physical impossibility, you start to think, 'What the f**k is wrong with me?' I think that took a greater toll on me, psychologically, growing up than what anyone could have said to me."