Lewis, 25, recently stepped out with a new sleek straight hairdo and some interesting outfit choices. Critics were quick to judge her style and some thought she'd had a nose job.
Osbourne wrote in her Closer magazine column: 'I cannot understand why there was such a fuss over pictures of Leona Lewis wearing unusual dresses last week - she's a beautiful girl and I love it when women take a bit of a fashion risk!
'And people are so mean to speculate over whether she's had a nose job or not. I have no idea if she has or if she wants one, but I think she looks beautiful whatever.
'And if she did have one - so what? It's her face! If that makes her or anyone else feel more comfortable and confident, so be it.'