Macaulay Culkin has changed a lot between his hit film Home Alone and Thursday's shot of him rocking an emaciated old man look. Check out this slideshow for a look back at the actor's life in photos.

The former child star, now 31, was photographed this week on the streets of New York, and he is no longer the fresh-faced kid we all remember from films like My Girl and Richie Rich.

It appeared to many observers that Culkin -- who was caught in the photo sporting a thin, blonde-to-white beard and disheveled hair and holding a Red Bull -- had aged decades since the last time he was photographed.

But Macaulay Culkin is healthy, one of his represenatives said after the photo was posted online.

Macaulay Culkin is in perfectly good health, the actor's rep told RumorFix. For Entertainment Tonight or any media outlet to speculate otherwise is reckless, thoughtless and irresponsible.

Entertainment Tonight released the scary photos on Thursday. The photos have left many wondering why he looks so disheveled, and ET has said it plans to reveal more photos of Culkin Thursday night.

The picture quickly became a trending topic on Twitter, as people posted comments ranging from words of sympathy to concern that he may be anorexic or on drugs.

Twitter user @BetterThanToday had some harsh words to say in a Thursday tweet: Looks like Macaulay Culkin was Home Alone for a bit too long. They forgot to leave him food before they left.

But other users, like @Wendy2812, felt bad for him instead. She tweeted the following on Thursday: So sad to see him like this - he was a legend in the home alone films!!

Check out this slideshow for a range of photos from each stage of Macaulay Culkin's life.

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