Actress Demi Moore seemed happy to embrace her 49th birthday Friday despite weight loss rumors.

My birthday starts with a bang and some serious monkey business, pursemonkey may never be the same! she posted on Twitter along with a picture.

However, sources have told US Weekly and the Daily Mail that Moore has suffered dramatic weight loss in the face of rumors of infidelity around her husband, Ashton Kutcher. 22-year-old Sara Leal has claimed she slept with the actor in September on the weekend of his six year wedding anniversary with Moore. The Two and A Half Men star is 16 years younger than Moore.

She is superskinny, and it's hard to look at, one friend told Us Weekly. She has reportedly joined a juice-cleanse service, but appeared frail and boney leaving a nail salon on Thursday.

Another friend says she has lost weight and its related to personal issues. She's very upset, and hasn't been eating, says the source. It's taking a toll.

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