Mischa Barton

Danger diet! Ever since pics of the star’s cellulite and fuller thighs appeared in the press, Mischa has embarked on a beyond-strict regime, cutting out all sugar and fat from her diet and sending her BMI plummeting to 15 (18.5 is healthy).

She says: “I’ve just been watching what I eat. I have cut back on fatty foods a bit. My time in India and Paris really just helped me lose a little bit of weight.”

Going too far? Producers on Mischa’s new TV show, A Beautiful Life are said to have insisted she gain weight – “[She] has the part on condition she does not lose weight – they want her to put weight on if she can.”

Lindsay Lohan

Danger diet! According to Us Weekly, the troubled actress takes the drug Adderall – used to treat ADD – which also acts as a powerful appetite suppressant.

The effects: “She pops Adderall like breath mints, which is why she stays cranked for days and days at a time,” spilled a close source. “She is jittery and unable to concentrate. She’ll eat one meal every two days and often subsists on soft drinks only.”

Addicted to thinness? “She can’t stop looking at herself,” said a pal. “She’s happy when she can see her ribs.”

Nicole Scherzinger

Danger diet! In-fighting within the PussyCat Dolls and constant jetting around the world to keep an eye on her F1 racer boyfriend, Lewis Hamilton, has meant no time to eat and whittled Nic’s frame down to seriously skinny proportions.

In denial: “I have gained a lot of weight over the last few weeks,” the 30-year-old insisted recently. “I get to eat in all of my favourite restaurants every night, I stuff my face.”

Nicollette Sheridan

Danger diet! The former Desperate Housewives actress is said to have cut all types of fat from her diet – with extreme consequences! Onlookers say Nic “freaked out” in an LA Starbucks recently, when the barista gave her regular milk. “She was yelling that she is trying to watch her weight and that the barista probably did that to her purposely just because she was Nicollette Sheridan.”

Nicky Hilton

Danger diet! The socialite’s weight famously yo-yos, but she was recently spotted almost looking like a ‘lollipop head’. And Nicky, who in the past, was said to have called Mischa Barton a “fat pig”, is rumoured to have become increasingly obsessed with her portion control – now only eating tiny amounts.

Annalynne Mccord

Danger diet! The Beverly Hills 90210 star is one of the thinnest women on US TV and 90210 sources claim the actress’s weight is around 45 kilos.

Hit show pressure: “[90210 producers are] trying to pull in the Gossip Girl audience and that’s the image of hyper-skinny models,” spilled a source. But the actress – the girlfriend of Twilight’s Kellan Lutz – who also starred in cosmetic surgery drama Nip/Tuck has snapped back, “[Critics] weren’t [able to] attack our acting chops… so bulimia, let’s try that.”

Tara Reid

Danger diet! After her recent stay in rehab - where most celebs gain weight Tara, who has given up the booze that used to help her pile on kilos, unveiled sticking out shoulder blades shoulder bones at a Perez Hilton bash, recently.

"I'm not too thin," she slammed. "I go up 10lbs, i go down 10lbs

Sam Ronson

Danger diet! “Sam has gotten so thin from Red Bull, cigarettes and stress related to life with Lindsay,” a pal spilled recently. Adding that the DJ has slimmed down as much as possible because “[she] loves being skinny.” And Sam, who is rarely seen eating, favours a super-strict approach to what she eats. “Sam is disgusted by overweight people,” says a friend.

Cameron Diaz

Danger diet! Cam’s noticeably lost weight over recent weeks, showing off a super-slender waist and legs at last month’s Kid’s Choice Awards. And sources say the weight’s been dropping off after a series of rows with her man, Paul Sculfor, over his commitment issues.

Bizarre meal plan: Cam’s embarked on the ‘Nothing White’ eating plan, which bans all white foods, including white sugar, white rice, potatoes, white flour, bread, cakes, pastry, pasta and noodles.

Tori Spelling

Danger diet! Tori’s protruding bones and stick-thin frame have become the talk of Tinseltown and the reality TV star – now weighing in at just 43 kilos – admits that often the only thing she will eat in a day are leftovers from her kids’ plates, such as a bite of a hog dog, a single French fry or a floret of broccoli!

Lydia Hearst

Danger diet! At just 40 kilos, the pin-thin Manhattan socialite is one of the skinniest celebs and late last year, the 24-year-old was rushed to hospital suffering from kidney stones. But her slender physique is widely celebrated across the pond and she’s won both Model Of The Year and Best International Supermodel awards.

Sharon Stone

Danger diet! The famously litigious actress has sued anyone who suggests her face and body are not 100 per cent natural. But she has admitted in the past to having iron willpower when it comes to dieting – “I just stopped eating,” she said of creating a “feral” look for Basic Instinct 2. “I wanted a moment where I would lean over in this backless dress and you would see the ribs in my back.”