Arriving at the fashion shoot, Lindsay Lohan was on the verge of collapse. Behind her outsize shades, the starlet appeared nervous and jumpy, and constantly complained of feeling ill. There were mutterings among her people: call a doctor – Lindsay needs a shot to “perk her up”. And, though the mysterious shot never materialised, it was clear that a private physician wielding a syringe was as much a part of her life as first-class air travel and a constant trail of paparazzi.

Lohan is not alone. At a comeback concert in Miami last month, Britney Spears reportedly demanded an “emergency” injection of vitamin B12 to revive her flagging energy levels before she went on stage. Asked about the incident afterwards, a spokesman for the singer shrugged. “I wouldn’t be surprised,” he said. It was as if Spears had just downed an espresso or a wheatgrass juice.

In the fast-living but insanely health-obsessed world of Hollywood, being injected with a “performance” shot – a cocktail of vitamins or hormones designed to put you back on form – is now as commonplace as having Botox. Geri Halliwell has used vitamin shots to see her through her diets. Robbie Williams has resorted to similar pick-me-up jabs to help him to recover from the twin rigours of touring and partying. Even in Britain, a quick shot is increasingly seen as an easy antidote to the tribulations of modern celebrity life. The artist Tracey Emin recently revealed that she has an occasional vitamin jab to keep her going. “Exhausted,” she wrote in her diary after a trip to Venice before the Biennale. “I went to have a vitamin B12 injection. Pity they only last two weeks.”

Such vitamin shots are nothing new – Margaret Thatcher is said to have had B12 injections to help her to survive on four hours’ sleep a night. But the number of civilians wanting them is rising exponentially. Heather Bird-Tchenguiz, wife of the property magnate Robert Tchenguiz and owner of HB Health anti-ageing clinics on both sides of the Atlantic, says she has seen a huge surge in the demand for injectable lifestyle vitamins. “People lead busy, tiring lives, and I believe there are benefits for those who use these performance injectables responsibly, under medical supervision. I have used vitamin and mineral injections myself. I have used a mixture of B complex, vitamin C and zinc to recover from illness or to help with tiredness. Injections can be very effective if you aren’t getting enough from oral supplements.”

Health is not the only reason people are demanding vitamin shots, however. The supermodel Cindy Crawford, now 41, recently admitted that her ageless looks were largely down to the skill of her cosmetic surgeon, Jean-Louis Sebagh. “I’m not going to lie to myself,” she said. “Past a certain age, creams work on the texture of your skin, but in order to restore elasticity, all I can really count on is vitamin injections, Botox and collagen.”

Plum Sykes, the author and New York society queen, also attributes her perfect skin to vitamin shots. She sees the hottest dermatologist in Manhattan, Steven Victor, who injects her skin with his vitamin C solution, which also includes traces of vitamins A, B and E and zinc and copper. Fergie, too, is said to be a devotee of the treatment. “I see him every four months or so,” Sykes says. “Your skin is pricked all over by these tiny needles, like acupuncture, which injects vitamin C just below the skin’s surface. It’s wonderful – and addictive!”

Addictive it may be, but the new shot culture isn’t without its dangers. A cursory search of the internet reveals injectable vitamins of every type for sale for DIY use, including the potentially dangerous vitamin A, which is implicated in an increased risk of cancer and birth defects. You can buy ultra-high-dose vitamin A, direct from Romania, for less than £10 for five phials.

Most British nutritionists throw up their hands in horror at the idea of people self-administering. “Vitamin injections are an extreme and dangerous fad,” says Claire MacEvilly, of the British Nutrition Foundation. “Overinjecting non-water-soluble vitamins A and D is easy and a real cause for concern. It can cause cramps, nosebleeds, nausea, blurred vision, dry skin, liver disease, weight loss, kidney stones and permanent kidney damage, irritability and jaundice. In the most extreme cases, it can lead to death.”

But vitamin therapies are just part of the lifestyle-injections story. The needle is increasingly seen as the answer to every conceivable modern ill. Flabby thighs? One jab of Lipostabil, and you’ll melt that fat away. Sex drive not what it used to be? Break out the testosterone and watch that lion roar. Though nobody in the medical world will talk about it openly, there’s a tacit understanding that almost anything is available to those who are prepared to pay. Rumours abound of doctors being asked to inject adrenaline – usually used to restart stopped hearts – or to slip a bit of something in with the vitamins to help a sluggish libido.

Even legal shots are entering realms that, only a few years ago, would have been seen as perilous ground. In America, there has been a huge rise in the use of human growth hormone (HGH) injections as an anti-ageing tool. A 2005 report estimated that 20,000 to 30,000 people in the USA were using HGH shots as an anti-ageing therapy, at a cost of up to $1,000 a month, even though such use is illegal in America. Anna Nicole Smith took the hormone regularly (the coroner who examined her body found that she had blood poisoning probably caused by an injection piercing an abscess on her bottom), and Sylvester Stallone was recently detained by Australian customs officials who found 48 phials of HGH stuffed in his luggage.

Bird-Tchenguiz has tried HGH in Britain, where its use is permitted, with, she says, good results. “I used HGH after I had had my appendix out and developed an abscess. I was thin and too weak to exercise. I had injections for a couple of months and saw the muscle mass increase. It also provided energy. I also used it to get my hormone levels back to normal after giving birth and a year of breast-feeding, when I wanted to conceive my next child, and once for a couple of weeks to lose weight before a holiday. It works.”

She admits, though, that some people are turning to such shots for the wrong reasons. “There are the health enthusiasts like myself, who want to go the route of prevention rather than cure,” she says. “If you want to run a Ferrari at peak performance, you have to provide the correct quality of petrol, oil, spark plugs and so on. But there are those who are in it because they do not want to change their lifestyle and are looking for a quick fix – often pill-poppers looking for something that gets more results. For a time, they enjoy the benefits – increased muscle mass, decrease in body fat, more energy, a body that performs as it did when it was younger. But if you ask a Ferrari to perform at peak performance without providing the right servicing, it will eventually burn out.”

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