The actor cut a gaunt figure as he stepped out in London for a theatre visit over the weekend.
An unshaven Tom was looking noticeably thinner than he did earlier this year, as he watched William Shakespeare's Richard III at the Globe Theatre.
Tom's family had previously voiced concerns for the actor after he quickly dropped 15 pounds after Katie sensationally filed for divorce back in June.
A source told Grazia magazine: "Tom's friends and family have urged him to take a break, but he has brushed off their concern.
"He is refusing to slow down and is trying to soldier on. He doesn't seem to be himself. He hasn't been working out like he normally does and doesn't appear to be eating well at all. His clothes just hang off him."
The source continued: "His way of dealing with this is to throw himself into his work, but as a result he's not looking after himself, and he risks cutting himself off from people who care about him and want to make sure he's OK."
> IN PICS: CELEB FAT FIGHTERS
At her thinnest Natalie wanted the whole world to know she'd lost weight. An inevitable work out DVD followed.
The Steps singer managed to shed the weight she gained after the band split, but then she fell pregnant and battled to lose it since.
Dawn French was always been known for being a bit on the larger side, and that's why we loved her. Well, there's less of her to love now as since her split with Lenny she's shed a fair few pounds.
James Corden's role in <em>One Man Two Guv'nors</em> helped him to shift over five stone.
That picture on the left actually scares us. It's like she wants us to motorboat in that cleavage. Bleugh.
It was revealed that Geri's dramatic weight loss was due to an eating disorder. Luckily she's settled back to a healthy weight now.
Gastric-band-gate swept the nation when it was revealed Fern hadn't exactly told the truth about her weight loss.
He's the man of the moment on The X Factor, but after the original Take That split Barlow ballooned.
TOWIE's Gemma shed four stone on a bid to win Mick Norcross. She gave up the bags of crisps but didn't manage to bag the bloke. Good job she's got Arg now then.
Pete's frame isn't the only thing shocking here. WTF is with that hair? Anyway, Pete shed the pounds when he split with Jordan. We didn't hear anything about that?
Eh up, don our Kerreh look slim. Must 'av been on t'Weight Watchers.
Jack Osbourne has struggled a lot with his size and is still yo-yoing with his weight now.
Gerard Butler has never exactly been a porker, but he's swapped his stocky frame for a much leaner one.
Jessie Wallace looked unrecognisable after slimming down, but since returning to Easties, Jessie has regained Kat's curvier figure.
<em>Superbad</em> actor Jonah Hill made jaws drop across the world when he unveiled his new look at an awards bash. He's hoping to lose more too.
Former Emmerdale actress Pauline Quirke lost several stone after being told she was morbidly obese.
Bristolian comic Justin Lee Collins has gone from rock-sized to rock star after dieting.
The once teeny weeny, leather-chaps wearing Christina Aguilera got tongues a-wagging when she ditched her slight frame.
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