Joe McElderry
Joe McElderry (see pictures above) rose to fame at the age of 18 after winning The X Factor in 2009.
But after he parted ways from Simon Cowell’s record label, he went back home and put on some weight.
And last year a picture of Joe during an appearance on This Morning went viral as people on social media commented on his weight.
At the time, he tweeted: “Oh don’t you just love the worst angled photo ever that makes you look like a slug!"
Joe has since hit back at critics after shifting a few pounds and sharing a topless picture of himself online showing his slimmer look.
Craig David
Craig David became a big star after featuring on Artful Dodger’s single Re-Rewind in 1999.
Back then we knew him as a slightly cheesy, skinny pop star but, when his star appeal started to wane, he moved to Miami and became a healthy muscle man.
And, luckily for us, Craig isn’t afraid to whip off his top and show off his toned torso on social media.
Renee Zellweger
Renee Zellweger played the loveable and curvy Bridget Jones in the 2001 film Bridget Jones’s Diary.
She piled on a few pounds for the movie but usually has a much slimmer figure.
But it seems the actress may have refused to gain weight again for the new upcoming Bridget Jones film, Bridget Jones’s Baby, as the character is much thinner than in the original movie.
Leon Jackson
Leon Jackson won the fourth series of The X Factor in 2007 but his music didn’t set the charts on fire for long and he was soon dropped from Simon Cowell’s record company.
But the singer surprised fans recently with a picture he shared on Twitter.
The musician has clearly been in the gym as he posed for a topless selfie in which he has a very toned tummy.
Duncan James
Duncan James was a member of boyband Blue from 2000 to 2005.
But when the singer returned for a reunion with the rest of the group in 2009 he looked a lot different from his former skinny self.
The star is a regular in the gym and is more than happy to share topless selfies showing off his rippling muscles on Instagram.
50 Cent
50 Cent shocked fans when he slimmed down for film Things Fall Apart in which he played a cancer sufferer.
But the usually ripped star soon bulked up again after the film.
Christian Bale
Christian Bale lost a huge amount of weight for his role in The Machinist and weighed a tiny four stone.
The actor soon piled on the pounds again though and bulked up for his role in Batman.
Matthew McConaughey
Matthew McConaughey is often pictured on a California beach displaying an impressive six pack as he goes for a run.
But he drastically changed his appearance and lost weight for his role as an AIDS sufferer in film Dallas Buyers Club.
He said of his weight loss: “It was tough going, I’m not going to lie. The dieting was pretty hardcore. I was losing 7lbs every week.”
Chloe Madeley
Chloe Madeley was something of a regular on the red carpets of movie premieres with her television presenting parents Richard and Judy Madeley when she was younger.
She has even tried her hand at hosting TV herself along the way.
But she is now better known for her super healthy lifestyle and often posts pictures of her impressive figure online.
Rhydian Roberts
Rhydian Roberts shot to fame on the fourth series of The X Factor in 2007.
He became known as the quirky Welsh classically trained singer and greatly impressed the judges with his vocal ability.
The musician now performs gigs around the country and also appears in theatre productions.
He’s certainly bulked up a bit since his TV talent show days.