Bookshelves are now groaning under the weight of new diet books, as a raft of celebrities offer advice on how to minimise those curves and reach so-called physical perfection.

Liz Earle's telling us to juice, Davina McCall's banishing sugar, while TV presenter Anna Richardson uses psychology to help us master our muffin tops, all in new books.

Every year, we gorge on advice from the rich and famous, from Gwyneth Paltrow and Cameron Diaz to Victoria Beckham and Miranda Kerr, as to how we can achieve their enviable physiques.

Serial dieter, New Yorker Rebecca Harrington has tried them all, from the weird concoctions Elizabeth Taylor would consume to retain her hourglass figure, to the 'sea vegetables' Madonna existed on and the 'salt water flush' she used to channel her inner Beyonce.

Today, Harrington, 29, is the same size she has been for a while - she won't reveal her weight or her dress size - but she stresses that with every celebrity diet she's tried, she put any weight she lost back on again immediately afterwards.

Now, she has rustled up I'll Have What She's Having, a witty, tongue-in-cheek book which charts her experiences of the weird and wonderful celebrity diets she has followed and the effects they had on her - a mix of fainting spells, spots and potential salmonella.

"When you Google celebrities, you get celebrity diets at the top of the page. Almost everyone famous provides an eating plan, so it was an easy one to follow," says the journalist and author.

"I think that Gwyneth Paltrow's diet is a really good one, if you're a millionaire, because all the ingredients cost so much, but a lot of the older celebrities followed regimes that were really gross. In many cases, dieting is just making normal food disgusting."

She cites the late Hollywood star Elizabeth Taylor, who would take a potentially delicious fillet steak and place it on a piece of bread slathered with peanut butter. Harrington tried it but couldn't eat the concoction, despite being starving hungry.

"The steak's juices mix with the peanut butter in an unappealing, oily way. I have three bites then throw the rest out," she recalls.

Legendary Thirties actress Greta Garbo dieted throughout her life, loved fad diets and was a great follower of self-styled 'doctor of natural science' Gayelord Hauser, nutritionist to the stars. Harrington found her regime strange, to say the least.

"Some publications even speculated that the two were having an affair based around their shared love of disgusting food," Harrington observes.

She tried to follow Hauser's principals - he believed that if you fuel your body with 'wonder foods', such as brewer's yeast, wheat germ and molasses, you would live to be 100.

But finding edible yeast in the shops was difficult, although she found some in a health food store which she could sprinkle on cereal.

"Dinner was terrible, based on Hauser's meal for Garbo the first night he met her - a veggie burger consisting of wild rice and chopped hazelnuts, mixed with an egg and fried in soybean oil, plus a dessert of broiled grapefruit with molasses in the centre."

Harrington recalls that the veggie burger tasted predominantly of eggs, the hazelnuts were an unpleasant surprise and the grapefruit dessert tasted medicinal.

She says she gained wait on Cameron Diaz's diet, because it was more about bodybuilding than shedding pounds, but that on Beyonce's diet, she lost about 10lbs in 10 days.

"The problem is, you have to exercise for two hours a day, and I just couldn't fit that in and sustain it," she recalls.

She followed Beyonce's 'Master Cleanse', which involved consuming only lemonade made out of cayenne pepper, lemons and grade-B maple syrup nine times a day. No food allowed.

"You also have to consume something called the 'salt water flush' [salt water that you drink while looking at yourself in the mirror], which is supposed to help your digestive tract."

Among the worst of the diets was that adopted by Marilyn Monroe, Harrington reflects.

"That diet made you feel so bad because it was almost all cream. She was clearly a drug addict. She ate raw eggs for breakfast every day. I thought I might get salmonella. Then, after a meal she'd have hot fudge sundaes."

In contrast, Victoria Beckham's 'Five Hands' diet - where you eat only five handfuls of food a day and then declare yourself full - was a lesson in abstinence.

She started the first day with two eggs - small ones, as they had to fit into her palm.

"I realise how little a palm actually holds," she notes. "I do not have the self-control of Victoria. I didn't have a fruit plate instead of a cake for my birthday, like she did in 2012."

Learning from one of Beckham's autobiographies that she wears fake nails, Harrington considered following suit.

"In my most desperate moment on the Five Hands diet, I considered getting very long fake nails like Howard Hughes, just so my hand would be slightly longer and therefore able to accommodate more food. And then I remembered that this is really the palm diet. Nails don't matter. And I sobbed on the street."

In fact, she admits: "I wanted to die by the end of that diet. I felt constantly hungry."

So what is her overall verdict? Are celebrity diets best avoided all together?

"In some ways, the best thing you can do is to approach these diets moderately - take a hybrid approach to them," she says.

"I definitely pay more attention to what I put in my mouth, but dieting is so regimented, it's sad. Yet there's this odd hopefulness to it," she adds.

She says that on most of the diets, she did lose weight, but gained it back almost immediately after eating a slice of pizza.

"I think the main thing I realised is how terribly hard it is to be an 'ideal' woman at any time in history," Harrington concludes with a sigh.

:: I'll Have What She's Having by Rebecca Harrington is published by Virago, priced £8.99. Available now