(CNN) - For 15 years, e-cigarettes have been billed as a safer alternative to traditional cigarettes.
But a study found e-cigarettes can make it harder to quit smoking and, in most cases, people end up vaping and smoking.
The study also found daily e-cigarette use can double the risk of heart attack.
If you're a dual user, that is vaping and smoking cigarettes every day, the combined risk for heart attack goes up five times.
E-cigarettes have lower levels of carcinogens than cigarettes. But researchers say the electronic versions have other toxins that can have detrimental effects such as increased cardiovascular and lung disease risks.
If you are a smoker, here's something you can do now: Stop.
Scientists say stopping smoking immediately drops your risk for heart attack.
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