A new report from the U.S. Centers for Disease Control and Prevention (CDC) says that just 15 percent of adults in the United States are now lighting up.

The figure has declined from the 17 percent of adults reported in 2014. The year before, almost 18 percent of adults were smoking.

defines current smokers as those who have smoked more than 100 cigarettes in their lifetime and now smoke every day, or at least on some days. The report does not refer to electronic cigarettes.

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Why Is The Rate Declining?

VJ Sleight, a tobacco treatment specialist based in California, said the drop in smokers is a good thing, but there are still about 45 million people in the U.S. lighting up — and that’s nothing to celebrate.

The barriers to quitting include inadequate medical coverage. Some people can get medication but not the right type, or the medication is not covered for the duration needed to help people quit.

What’s helping people quit?

The CDC’s campaign “” was effective at educating smokers about how many complications the habit can cause.

“Most of them have absolutely no idea the extent [of the damage] that smoking has done to the body,” Sleight told Healthline.

Smoking has also declined in areas where taxes have been raised and cigarettes have been banned.

“I am seeing a lot of clients who are stopping because it is too difficult to smoke anymore. They feel like pariahs. They are having a difficult time finding a place to smoke,” Sleight said.

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The E-Cigarette Factor

Increasing e-cigarette use may also explain why traditional cigarette use is down.

Brad Rodu, D.D.S., a professor at the University of Louisville and endowed chair of Tobacco Harm Reduction Research, recently addressed this issue on his blog.

Rodu noted that almost 2 million former smokers were currently using e-cigarettes in 2014. 

“While it is not possible to prove that they had used e-cigarettes to quit, 85 percent of these former smokers had quit five years or less prior to the survey, making it plausible that e-cigarettes played some role in their becoming or staying smoke-free,” he said.

Rodu said that cigarette smoking in the U.S. continues to decline.

“Rather than impeding progress, e-cigarettes may be accelerating a smoke-free revolution,” Rodu added.

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The Fight Must Continue

Sleight said the battle to lower the number of smokers in the U.S. is far from over.

“This is costing us, taxpayers, a tremendous amount of money,” Sleight said.

“The tobacco companies are fighting back and they’ve got a lot of money to spend,” she added. “The public needs to be aware that this is still an ongoing issue.”

Cliff Douglas, a tobacco control expert with the American Cancer Society, echoed Sleight's comments.

He said traditional cigarette smoking may be down, but people are still using other deadly combustible products such as cigars and hookah.

Douglas called for the U.S. Food and Drug Administration to approve graphic warning labels. He wants states to continue to enact strong tobacco control laws aimed at smoking cessation and prevention.

Teens Require Special Focus

Smoking may be down among adults, but what about those under the age of 18?

“In fact, some groups have seen increases in tobacco use. Young people have not seen the same declines as adults have experienced,” noted Dr. Michael B. Steinberg, an associate professor at the Rutgers Robert Wood Johnson Medical School and director of the Rutgers Tobacco Dependence Program.

“As far as teens go, the smoking rates have dropped but vaping rates are going up,” Sleight added.

She said that e-hookahs are popular because the teens claim they do not contain nicotine.

“But we don’t know if teens using them will become addicted to nicotine and/or switch to tobacco cigarettes,” she said. “Most likely the disease profile for using e-cigs will be very different than tobacco cigarettes, but it will be decades before we know what the long-term effects will be.”

Teens aren’t the only ones turning to the act of smoking.

Steinberg said people with mental health issues, substance abuse and multiple diseases continue to smoke traditional cigarettes.

“These high-priority groups need much more attention if we hope to reach our public health goal of continued improvements in tobacco rates,” he told Healthline.