Embattled actress Amanda Bynes has sparked fears for her health after claiming she has an eating disorder.

The Hairspray star revealed in an interview last month (Feb13) that she wanted to lose 20 pounds (nine kilograms) in a bid to slim down, explaining to Us Weekly, "I gain weight quickly so I need to work out constantly."

Bynes took to her Twitter.com page earlier this week (begs01Apr13) to declare "Skinny's The F**k" - and she returned to the site late on Thursday (04Apr13) to make a startling revelation.

She told fans, "I have an eating disorder so I have a hard time staying thin."

The tweet came after she re-iterated her pledge to take legal action against media outlets, stating, "I'm suing certain blogs and magazines saying I have a mental illness! They take pictures anytime I've gained weight then write a fake story!"

Last month (Mar13), Bynes threatened to sue two media outlets after editors questioned her bizarre behaviour following the emergence of photos showing the star walking around New York with a shirt over her head.

Bynes' personal life has hit headlines for all the wrong reasons in recent months thanks to her driving and legal woes, and on Tuesday (02Apr13) she failed to show up for a Los Angeles court hearing in her suspended licence case. A judge granted a continuance and set a new pre-trial date for May (13).