The singer and rapper Lizzo has spoken of how she was affected by seeing negative and stereotypical images of plus-size bodies as a child.

“I would watch things on television and look at magazines and I would not see myself,” she said. “When you don’t see yourself, you think something is wrong with you.”

Lizzo, whose real name is Melissa Jefferson, said this lack of representation affected her mental health. “You want to look like those things and when you realise it’s a physical impossibility you start to think, ‘What the fuck is wrong with me?’,” she said. “I think that took a bigger toll on me, psychologically, growing up than what anyone could have said to me.”

The singer, who has been acclaimed for being a plus-size celebrity, also talked about the dangers of using body positivity as a marketing tool.

“Anybody that uses body positivity to sell something is using it for their personal gain,” she said. “We weren’t selling anything in the beginning. We were just selling ourselves and selling ourselves on the idea – selling ourselves on ourselves.”

Interviewed in the latest edition of British Vogue, the classically trained singer also reveals the anxiety that fuels her turbo-charged performances. “When I get really, really anxious before a show, I just go harder and harder and harder when I’m performing and I just go crazy,” she said.

“I don’t know why, but my anxiety sometimes fuels who I am as a performer and who I am as an artist. I don’t know if my body just, like, out of a desperate need to find a place for my anxiety or find a use for it, takes it and puts it there.”

The December issue of Vogue, which features Lizzo wearing a black bustier dress by Versace, an Adrienne Landau feather boa and Chopard earrings on the cover, marks the two-year anniversary of Edward Enninful’s editorship.

It has two cover stars, the other being the actor Emma Watson, but the choice of Lizzo underlines Enninful’s commitment to championing diversity: His first cover featured the Ghanaian-British model Adwoa Aboah, while later cover stars have included Jourdan Dunn, Naomi Campbell and Zoë Kravitz.

“Seeing such a positive force for good on our cover in all her glory makes me realise how far we have come. I’m so pleased that inclusivity remains at the core of British Vogue,” Enninful wrote on Instagram. He added: “Seeing someone as amazing as Lizzo on a magazine cover has at last begun to feel normal. How incredible is that?”

Earlier this year, Lizzo’s song Truth Hurts went to number one on the US Billboard charts, making her the first solo black female singer to achieve the feat since Rihanna in 2012.