If you have lung disease and you're a smoker, you undoubtedly know the importance of breaking the cigarette habit. You may even have tried to quit smoking before but to no avail. Could electronic cigarettes -- also known as e-cigarettes -- be the answer?

These battery-powered devices look like real cigarettes, have a light-emitting diode (LED) on the tip that lights up when you inhale and even produce fake smoke in the form of water vapor. They also deliver nicotine via cartridges, but spare you the tar, carbon monoxide, formaldehyde and other toxins found in tobacco smoke. 

If e-cigarettes sound too good to be true, that's because they probably are. With a dearth of rigorous studies on their safety and effectiveness, experts are increasingly concerned that e-cigarettes may do little to help you stop smoking -- and may actually do more harm than good. 

Some manufacturers of e-cigarettes tout their products as an effective form of nicotine replacement therapy. And, in theory, they could work, since the principle is the same. The e-cigarette's cartridges are available in progressively lower concentrations of nicotine, so you can wean yourself off nicotine over time just like with traditional nicotine replacement products. 

So what's the problem? For one thing, some e-cigarettes may not deliver enough nicotine to the bloodstream to effectively suppress cravings. In one study, published in Tobacco Control, the investigator compared levels of nicotine in the blood of 16 smokers after they smoked two of their usual brand of cigarettes, puffed on two unlit cigarettes or "smoked" two brands of e-cigarettes, each containing a 16 mg (high) cartridge of nicotine.  

After smoking the e-cigarettes, participants had nicotine levels virtually the same as they did after puffing on an unlit cigarette and significantly lower than the blood nicotine levels detected after they smoked a conventional cigarette. In addition, the smokers' heart rate increased after smoking tobacco but not after using the e-cigarette or unlit cigarette, again suggesting a negligible delivery of nicotine to the bloodstream with the e-cigarette. Another problem: Some cartridges may contain more or less nicotine than noted on the label. 

Our advice: Some manufacturers and retailers of e-cigarettes claim these products are healthier than normal cigarettes and can help you quit smoking. But in the absence of scientific evidence to support those contentions, it's best to avoid e-cigarettes until more research has been done. For now, if you're trying to quit smoking, stick with proven, FDA-approved stop-smoking strategies.          

Article taken from John Hopkins Health Alerts.