Story highlights Smoking is still the leading cause of avoidable death in the United States

E-cigarettes are being used by more people as a nicotine alternative

Opponents worry e-cigarettes are being marketed to kids, who may be hooked for life

If the tiny sample of smokers in a new study in the British journal Lancet are any indication, electronic cigarettes might be slightly more effective than nicotine patches in helping people quit smoking.

Great, right? Except another new study from the Centers for Disease Control and Prevention suggests more children and teens are trying them.

The implications of both these studies means electronic cigarettes have been getting a lot of attention lately. Just what e-cigarettes are and what role they should play in helping people quit smoking depends very much on who you speak with about this topic.

Smoking is still the leading cause of avoidable death in the United States. The devices are not one of the FDA-approved methods to help people quit, but many people are using them this way. A growing number of scientists are studying them to see whether they may be a way to end an epidemic.

The topic, though, remains as polarizing a health issue as sex education or diet sodas

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An e-what?

The e-cigarette was actually developed by a pharmacist in China.

The pharmacist, Hon Lik, was a three-pack-a-day smoker. That was nothing unusual -- more than 300 million people in China are regular smokers. But when Lik's father, who was also a heavy smoker, died of lung cancer, Lik decided he had to come up with an alternative that wouldn't kill him.

Most scientists believe nicotine itself, while highly addictive, is not what causes cancer for smokers or for the people around them who breathe their second-hand smoke. Instead, it's the toxic chemicals that are created when tobacco and filler products burn that are dangerous.

If there was a way to get nicotine addicts their fix without the burn, you just might avoid the health problems. Nicotine then becomes as harmless as any other addictive substance, such as caffeine, some experts say.

So Lik developed an e-cigarette -- a device that uses a small battery to atomize a pure liquid solution of nicotine. Nothing is burned. There is no ash. There is no smoke. There is nicotine, and then there is flavoring added for taste.

Essentially the person using these inhales a kind of vapor that looks like fog from a fog machine. A recent review of all the scientific research done on e-cigarettes by Drexel University professor Igor Burstyn concludes "current data do not indicate that exposures to vapors from contaminants in electronic cigarettes warrant a concern."

In plain language, Burstyn concludes: "It's about as harmless as you can get."

"I wouldn't worry at all if someone was smoking one of these by my kids," Burstyn said. "From a pure health perspective, these are not as bad as a cigarette."

E-cigarettes came to the U.S. market around 2009. The CDC now estimates about one in five American smokers have tried an e-cigarette -- that's about 6% of all adults.

There are e-cigarette stores, but now you can also buy them online or in convenience stores. Some look like regular cigarettes; some look like pens or thumb drives.

First you buy a starter kit, which costs between $40 and $130. In the kit is the e-cigarette, a charger and a few cartridges. The cartridges typically last as long as a 20-pack of cigarettes and sell for around $10. You can also buy a bottle of e-liquid to refile the cartridge yourself.

The anti-e-cigarette camp

Critics point out e-cigarettes come in kid-friendly flavors such as gummy bear, atomic fireball candy and cookies and cream . It makes them worry that e-cigarettes will become a gateway to encourage kids to develop a lifelong nicotine addiction -- or worse, try the real thing.

Only about 20 states specifically forbid the sale of e-cigarettes to children.

Tobacco use has been on the decline with kids; it's about half what it was in the mid-1990s. But the latest CDC study shows a growing number of middle and high school students have tried e-cigarettes.

One in 10 high school students surveyed said they had tried e-cigarettes last year. That's double the number from 2011. One high school in Connecticut banned them after the principal said administrators dealt with at least one incident involving e-cigarettes every day.

CDC director Tom Frieden characterized this trend as "deeply troubling."

But as far as risky behavior goes, it's still a tiny fraction of students. The survey showed about 3% of these kids said they had used one in the last 30 days. By contrast, 39% of students said they drank some amount of alcohol in the past 30 days, 22% binge drank and 24% rode with a driver who had been drinking.

The real problem is that 88% of adult smokers who smoke daily said they started when they were kids, according to the CDC. Kids who start down the path to using e-cigarettes may stick with them for life.

"So much is unknown about them and what the long-term complications could be with their use," said the American Lung Association's Erika Sward. "Bottom line, we don't know what the consequences of using them are, and we are very troubled that kids would find them attractive."

E-cigarettes are unregulated in the United States; no laws make manufacturers tell you what you are actually inhaling. The unknown is one of the many qualities of e-cigarettes that the American Lung Association doesn't like.

It's "a complete unregulated Wild West," Sward said. She wants the FDA to move quickly with regulatory oversight, which she says would make manufacturers disclose what the actual ingredients are in each of the 250 or so brands available.

In 2009, a FDA test on a small number of e-cigarette samples found "detectable levels of known carcinogens and toxic chemicals to which users could potentially be exposed." They found diethylene glycol in one cartridge at a 1% level; this is an ingredient used in antifreeze and can be toxic to humans in large quantities. Diethylene glycol is also found in some dental products and in some pharmaceuticals.

After that study, the FDA banned the sale of e-cigarettes. They warned e-cigarette smokers that they were inhaling "toxic" and "harmful" chemicals. However, in 2010 , a court ruled that "the FDA had cited no evidence to show that electronic cigarettes harmed anyone," and stores could go on selling them.

The early e-adopters

On the other side of the debate are the passionate supporters of e-cigarettes. Many who use them say it is the first thing that has helped them stop using cigarettes -- something more than 90% of smokers fail to do with any of the existing FDA-approved methods. There are blogs and message boards dedicated to them. And there are countless impassioned testimonials from the people who use them.

Florida resident Craig Lashley says they've changed his life.

"I got tired of being like that little kid in 'Peanuts' who had the cloud of smoke following him all the time," Lashley said. "I didn't like the way I smelled when I smoked, and I didn't like what smoking said about me, especially to kids."

He discovered the e-cigarette about a year ago and hasn't smoked a regular cigarette since.

He says he smells better, feels better and spends a lot less -- about $10 a week on e-cigarettes. He used to spend about $45 a week on regular cigarettes.

"I like the feel of blowing smoke," Lashley said. "It seems to me like (e-cigarettes are) a healthier alternative."

A growing number of respected physicians and scientists agree, and they say these products could end a major health problem.

"Electronic cigarettes and other nicotine-containing devices offer massive potential to improve public health, by providing smokers with a much safer alternative to tobacco," the Royal College of Physicians says. "They need to be widely available and affordable to smokers."

The latest study, published in the British journal the Lancet, examined whether people who used them as an alternative to smoking would abstain from using regular cigarettes.

The New Zealand authors studied the behavior of 657 people who were trying to quit. One group got nicotine patches, another got nicotine e-cigarettes and others got placebo e-cigarettes without the nicotine.

Over a period of six months, only a tiny fraction of the people in the study actually quit smoking.

People using the nicotine e-cigarettes quit at a slightly better rate compared with those using the patch, though. Some 7.3% using the e-cigarettes abstained from smoking traditional cigarettes compared with the 5.8% who stopped with the patch. About 4.1% stopped with just the placebo e-cigarettes.

It was such a small number of people who quit that the authors concluded "more research is urgently needed to clearly establish their overall benefits and harms at both individual and population levels."

Dr. Michael Siegel , a physician who has spent the past couple decades working on tobacco control initiatives, has been surprised by the negative reaction to e-cigarettes from so many people in the public health sector. Siegel says the studies he's done have shown e-cigarettes are a help.

"True we don't know the long-term health effect of e-cigarettes, but there's a very good likelihood that smokers are going to get lung cancer if they don't quit smoking," he said. "If they can switch to these and quit smoking traditional cigarettes, why condemn them?"

Siegel theorizes the e-cigarettes might look too much like smoking.

"It's ironic the very thing that makes them so effective ... drives the anti-smoking groups crazy. But what makes them so effective is it mimics the physical behaviors smokers have, which is something the patch can't do."

Siegel does believe there is an urgent need for more regulations.

Ray Story, founder of the Tobacco Vapor Electronic Cigarette Association , agrees. He says his association has also pushed for age verification legislation.

"When you have these companies trying to promote these as something they are not, and you have stores that sell them in the candy aisle, you are going to have a problem," Story said. "If they are officially categorized as a tobacco product, you get an automatic age verification put in place.

"Nicotine is addictive, and we want the federal government to create guidelines and a structure that will confine these to being sold as adult products."

Lashley says no matter what the debate, he will continue to spread the e-cigarette gospel to his fellow adults.

So far, his co-workers have been receptive to the idea. He used to be the only one with an e-cigarette on smoke breaks. Now he says he's got more than a dozen colleagues doing the same.

One colleague, though, complained about it.

"He said 'I'm sick of all these people smoking electronic cigarettes," Lashley said. "When I asked him why he said. 'Simple, now I can't bum any off of them.' "