The 24-year-old singer, who recently gave birth to her first child with partner Simon Konecki, is happy being her size and does not think she needs to change unless her health worsens, reported Showbiz spy.
"I read a comment on YouTube that I thought would upset me 'Test pilot for pies' - but I've always been a size 14-16 and been fine with it. I would only lose weight if it affected my health or sex life, which it doesn't," she said.
Fashion designer Karl Lagerfeld and pop sensation Lady Gaga have previously criticised her size.