Poor Mischa Barton, as if she hasn't had enough on her plate already (no pun intended) - now movie bosses are telling her she needs to lose weight.

The troubled actress, who was forcibly taken into psychiatric care last month amid rumours of her party lifestyle getting out of hand, is reported to have been told by executives that she's too plump for her role as a model in The Beautiful Life.

Star magazine claims she was "shocked to tears" when she was told that she would need to slim down.

The mag quoted a source as saying: "She knows that means they are calling her fat behind her back.

"She knows she is heavier than she needs to be but to hear it like that? It really shook her. How can Mischa play a model when she's looking so heavy?

"She's broken down in tears more than once before shooting. It's a lot of pressure
for someone who is just out of hospital."

Mischa is said to be doing her best to lose weight as quickly as she can, but as we all know - it's a lot easier to put it on than it is to get it off again!

See our gallery of worryingly skinny stars...