Fifty years after the first Surgeon General’s report on tobacco in 1964, the latest report highlights improvements in American’s smoking habits, as well as a potentially new hazard for Americans’ health.

Smoking cigarettes kills about half a million Americans every year, and 16 million Americans are living with smoking-related health problems. These are costing the nation more than $289 billion each year in medical care and related costs.

The report acknowledged a new way of smoking — with electronic cigarettes or e-cigarettes, which are tobacco products with lower nicotine levels. More young people are using these products; the number of middle school and high school students who use e-cigarettes doubled from 2011 to 2012.

MORE: The Future of Smoking

“We need to monitor patterns of use of an increasingly wide array of tobacco products across all of the diverse segments of our society, particularly because the tobacco industry continues to introduce and market new products that establish and maintain nicotine addiction,” Dr. Thomas R. Frieden, the director of the CDC writes in the foreword of the report.

The report doesn’t conclude whether e-cigarettes are a healthy option to regular cigarettes, but says more study of these products are needed in order to weigh their risks and benefits. While they may contain less nicotine, some studies suggest that e-cigarette smokers inhale more deeply and therefore are exposed to higher levels of nicotine per puff than smokers of regular cigarettes. Others hint that because of e-cigs’ lower nicotine levels, smokers inhale less of the potentially harmful compound. And the studies on second-hand exposure showed that compared to regular cigarettes, e-cigs release nicotine but not other emissions such as carbon monoxide. So far, several states have banned e-cigarettes from non-smoking areas, but in coming months and years, more cities and states will likely turn to the Surgeon General and other public health authorities in deciding how to regulate e-cigarette use.

“Further research and attention to the consequences as well as regulatory measures will be necessary to fully address these questions,” the report authors write. They also recognize the urgent need for answers, since the popularity of e-cigarettes will only rise as continued regulation of traditional cigarettes increases. “The promotion of electronic cigarettes and other innovative tobacco products is much more likely to be beneficial in an environment where the appeal, accessibility, promotion, and use of cigarettes are being rapidly reduced,” they write.

(MORE: Smoke from E-Cigs Still Poses Some Second-Hand Risk)

The first Surgeon General’s report on tobacco made the connection between smoking and the risk of lung disease. A recent study credited this report, and the anti-smoking efforts it launched, with saving 8 million American lives from tobacco-related deaths. Still, Frieden and other public health experts note, more lives could be saved if people stopped smoking. Two decades ago men were dying faster than women from smoking-related illness, but numbers now show those rates are about even. And although smoking among youth has decreased, the report found that every day 3,200 children under age 18 try their first cigarette and 2,100 youth and young adults become what’s considered daily smokers.

The new report also highlights a long list of health problems, in addition to lung disease, caused by smoking, including diabetes, colorectal cancer, and facial deformities among babies whose mothers smoke.

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