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I've heard that e-cigarettes are a healthier alternative to regular cigarettes, but what's the real deal?
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E-cigarettes contain nicotine and other chemicals. They're designed to simulate smoking by vaporizing a solution of propylene glycol and/or vegetable glycerin, flavoring, and sometimes nicotine. The idea is that they can help smokers quit or reduce their dependence on regular cigarettes. However, there isn't much evidence yet that they work for this purpose, and some studies suggest that they may even be harmful in certain ways. For example, one study found that e-cigarette use was associated with an increased risk of heart attack and stroke. So it's important to talk to your doctor if you're considering using them.