Socialite Nicole Richie, whose rail-thin appearance in recent photos has stoked tabloid speculation of an eating disorder, has checked into a treatment facility to address her inability to gain weight, her publicist said.

"She is working with a team of doctors and specialists whose focus is nutrition," spokeswoman Nicole Perna said in a statement.

"It is important to Nicole that she achieves this goal in a healthy way as this is not a treatment for an eating disorder."

Richie, the 25-year-old daughter of singer Lionel Richie, has publicly acknowledged her obvious loss of weight in recent months, telling Vanity Fair magazine: "I know I'm too thin right now...I'm not happy with the way I look."

And she told People magazine that "stress" over the breakup with her former fiance had briefly affected her eating habits.

But she has vehemently denied as "rumour" media reports suggesting she suffered from an eating disorder.

Her admission to the unidentified facility has forced a delay in production of the latest installment of her popular TV reality show, "A Simple Life," producers said.

Postponement of the show came weeks after Richie and her "Simple Life" co-star, hotel heiress Paris Hilton, ended a feud that had kept the two on nonspeaking terms for over a year.

"We wish her a speedy recovery and fully expect the series will resume production at some point, hopefully in the near future," said Chris Alexander, a spokesman for 20th Century Fox Television.

News of Richie's decision to seek medical help first surfaced on the cable network that airs her show, E! Entertainment Television, and its Internet outlet, E! Online.