Survey: More than 2.5 million U.S. students say they currently use e-cigarettes

More than 2.5 million middle and high school students in the United States say they use e-cigarettes, according to a new National Youth Tobacco Survey.
Researchers say e-cigarettes continue to be the most commonly used tobacco products among students.
A total of 42% of those surveyed say they smoke frequently.
Almost 28% say they use e-cigs every day.