It was at a Ladi6 concert at the Powerstation recently that Nick Dwyer was tackled by a security guard.

He had taken out an e-cigarette and was taking a drag when she accosted him.

"But as soon as I said, 'no it's electronic', she was fine and started talking about getting one for herself," he remembers.

The breakfast radio host had tried several times to kick his smoking habit. Patches, lozenges, the Allen Carr quit smoking book ... nothing worked.

But when he started to have problems with his voice, he decided something had to be done.

The answer was e-cigarettes, filled with liquid nicotine and available in a range of flavours, including one similar to the Dunhill Blue he used to smoke.

Dwyer smokes them on air, in the back of taxis and even on planes.

"I haven't had a single cigarette in five months," he says. "I used to smoke a pack or a pack-and-a-half a day but I love this stuff. You get the nicotine hit and you're holding something that in every way, shape and form feels like a cigarette."

Now, the Herald on Sunday can reveal that electronic cigarettes are more effective in helping smokers quit - and keeping them smoke-free - than nicotine patches and non-nicotine cigarettes.

That is the finding in world-first research, which Auckland University associate professor Chris Bullen will present to the European Respiratory Society Annual Congress in Spain today.

E-cigarettes have been around for less than 10 years, but their popularity is soaring in the United States and Europe.

From a few thousand users in 2006 to millions this year, e-cigarettes are now a billion-dollar industry.

The proportion of US teenagers who say they have tried e-cigarettes has doubled to 10 per cent over the past two years.

In New Zealand, 6 to 8 per cent of young people say they have tried e-cigarettes; a third of those who smoke say they have tried "vaping", as it's been dubbed.

Next week, e-cigarette vendors will show their wares at an expo in Anaheim, California.

At Vapefest in Las Vegas the same weekend, more than 50 companies will offer free samples and discounts on the latest electronic cigarettes, ranging from traditional tobacco flavour to coffee, grape and cherry.

But in a throwback to the 1940s and 50s when tobacco companies paid Hollywood actors including Betty Grable, Jean Harlow, Clark Gable and Frank Sinatra to promote their product, a new generation of stars is now popularising e-cigarettes.

Jenny McCarthy, former Playmate of the Year and wife of Hollywood A-lister Jim Carrey, has built a mass media profile on American talkshow The View.

This year, she became the face of Blu e-cigarettes, one of the most popular brands in the US. She says in an TV advertisement that one of the reasons she switched to them is because smoking turns men off.

In another Blu TV advertisement, against a backdrop of fresh air and crashing surf, movie pin-up Steven Dorff proclaims: "I'm tired of being a walking ashtray ... We're all adults here. It's time to take our freedom back."

Sound familiar? Yes, individual freedom is the same mantra now chanted by tobacco companies around the world as they fight encroaching public distaste and government regulation.

And the Blu e-cigarette brand is owned by - uh-huh - Lorillard, an American tobacco company.

In New Zealand, scientists, doctors and public health workers are split on e-cigarettes. One half say we should steer clear of the latest addictive offering, lookalike cigarettes that keep smokers on a nicotine leash still held by Big Tobacco.

The other half say what the hell: if it helps people quit, why not go with it?

"There's vapour like smoke," marvels Matthew Theunissen. "It crackles like a cigarette, gets warm in your hand like a cigarette and there's that familiar sensation in the back of the throat."

Theunissen stopped smoking this week, one of a team quitting as part of the Herald on Sunday's Quitters campaign. The journalist, 27, had been 10 years on the baccy, but has now bought himself an e-cig and is impressed.

It is that sort of reaction that Christopher Bullen and his team of Kiwi researchers have seen among the 650 smokers they tracked.

E-cigarettes are more socially acceptable than cigarettes or patches, and people are willing to use them for much longer, Bullen says.

"E-cigarettes give the whole enjoyment of seeing the vapour cloud coming up, and there's the manipulation of the product in the fingers, which is cool and sexy."

Bullen says e-cigarettes are the biggest thing in smoking cessation efforts for decades.

"They have been bigger in sales and popularity than anyone ever forecast."

In his six-month study, to be published in The Lancet medical journal, one group of smokers was given e-cigarettes containing 16mg of nicotine. Another group received patches and a smaller number were given placebo e-cigarettes.

At the end of six months, 5.7 per cent of all participants had succeeded in stopping smoking. Just over 7 per cent of those smoking nicotine e-cigarettes had given up, compared to 5.8 per cent who were using patches and 4 per cent who were smoking non-nicotine e-cigarettes. Among those who did keep smoking, most of those with e-cigarettes managed to at least cut back their tobacco consumption.

Bullen said more research was required, but he expected it to show that e-cigarettes were about 25 per cent more effective than patches and 50 per cent more effective than zero-nicotine cigarettes.

It's the "cool and sexy" factor that the big tobacco companies are interested in. Britain has reported a 10-fold increase in e-cig sales between last year and this year, and ads like those fronted by Dorff and McCarthy have been given the credit. Simon Cowell and Kate Moss have been seen smoking them.

They have the kind of old-school Hollywood glamour and sophistication that cigarette advertisements used to have.

That's one of the biggest concerns for Marewa Glover, joint director of tobacco control research at the University of Auckland. She is willing to embrace e-cigs because they are one more tool to help people quit, though she worries about tobacco companies taking over the e-cig industry and again glamourising the image of people dragging on small white sticks.

"It's kind of a shame," she says. "We could have done a lot with e-cigarettes, but because tobacco companies have seen how they can use it for their benefit there will have to be wider regulation of e-cigarettes."

Otago University associate professor in public health Nick Wilson is far more dubious about e-cigs, saying tobacco companies were focused on profits and keeping people hooked.

"They won't be in it hoping to use e-cigarettes to reduce harm and get people on to the path of quitting. Fifty years of history shows they're not interested in the health of their customers."

In New Zealand, Imperial Tobacco Group says it is making good progress with e-cigarettes through its subsidiary Fontem Ventures, and expects to introduce its own products next year. "There is a grey area around the legal status of e-cigarettes, including in New Zealand," says Imperial Tobacco's market manager, Brendan Walker.

"The future of these products will depend on how countries decide to regulate them."

He rejects any suggestion the company is using e-cigs to make smoking acceptable to young people. "We believe that the decision to enjoy tobacco products is a choice for adults," he says. "We do not want children to smoke, or to use tobacco products."

It was a Tuesday morning in May, when Shimon Elbaz and his wife left their Jerusalem home, leaving their two young daughters in the care of their grandparents.

Two-and-a-half-year-old Naomi wandered into her grandfather's room, where she found a small bottle of liquid nicotine used to refill his electronic cigarette and drank from it.

Little Naomi was found in a dazed state and an ambulance crew took her to hospital. Her condition deteriorated over the next eight hours, and she died.

Clearly, the contents of e-cigs are dangerous when consumed in such concentrations - but how dangerous are they to e-cig users?

Last week, a French study made international headlines with the finding that e-cigs contained carcinogenic chemicals as harmful as those in tobacco.

But Bullen dismisses many of the study's findings. Yes, there are toxins in e-cigarette fluid, but they are no different from those in any nicotine replacement therapy, he says, "and still much lower than cigarettes".

Smokers could stay on e-cigarettes for the rest of their lives if they wished to, he says. Nicotine is far less dangerous than most of the chemicals in cigarettes - the chemicals that kill. "It's not the nicotine that kills you, it's the junk and the tar."

The only way - officially - to get nicotine e-cigarettes in New Zealand is to buy them online from overseas, although some corner stores and herbal high shops sell them. Smokers have been finding them fairly easily.

MedSafe has not approved any e-cigarettes for sale and it is illegal to sell any e-cigarette that claims to help people quit.

Nick Wilson says e-cig vapour can irritate other people's cardiovascular systems, and some airlines have banned them.

"The idea is to have a system where smart regulation maximises the benefits of switching and minimises the risks."

The Ministry of Health says there is not enough evidence to recommend e-cigarettes as a quit-smoking aid.

"The Ministry will be assessing new evidence as it arises, but in the meantime smokers should continue to use approved smoking cessation aids."

Tobacco researcher Murray Laugesen says the Government is standing in the way of smokers' human rights by making it difficult for them to obtain a product that could help save their lives. "They're entitled to obtain them as a lifestyle product without going to the doctor. You wouldn't have to go to the doctor to buy diet Coke," he says. "The whole thing is a tragic farce for smokers."

At the George FM radio studio in Ponsonby, Dwyer says despite using e-cigarettes, he no longer feels like a smoker. He can go to pubs and other places where once he might have been tempted to smoke; he's no longer constantly thinking about smoking.

"I'm still a nicotine addict, I love the stuff. But I don't have a cigarette smoking habit any more. When I see a cigarette or smell a cigarette, it grosses me out."

Dwyer isn't sure whether he'll ever give up smoking e-cigarettes. "Maybe I'll cut down. The end game would be to, but it's neat and it's not harming me."