Kelly Osbourne says the best thing about being slim is being able to buy jeans that don't give her a "willy" when she sits down.

The 25-year-old beauty - who has lost over 40lbs following her appearance on US TV talent show 'Dancing With The Stars' and a change in her diet - says her new figure has opened up a world of new flattering fashion possibilities.

She wrote on her twitter page: "I went on a shopping spree today and finally bought myself some clothes that fit!!!! i love retail therapy!

"all my jeans made me look like I had a willy when I sat down because they were to big, now I have ones that fit! Happy Days! (sic)"

Kelly also revealed shopping has become one of her favourite hobbies because it gives her a big confidence boost.

She said: "trying on clothes that you never ever thought would fit or look good on you is the most amazing feeling! (sic)"

Kelly recently admitted to giving up alcohol after meeting her fiance, model Luke Worrall, something which has contributed to her weight loss.

She said: "He's turned me into a better person. He really has. I didn't care before I met Luke. I was out every night, drunk. I didn't have somebody to be a better person for and then that all changed when I met Luke."