Initiatives like raising the price of tobacco, educating consumers on the dangers of smoking and efforts to help people quit are the primary drivers behind the decline, said King. Fewer young people are starting to smoke, older smokers are dying and others are quitting, he said.
When adding other categories, including e-cigarettes and smokeless tobacco, 19.3 percent of adults, or 47 million people, used tobacco products of some kind in 2017, according to the CDC. Cigars, cigarillos or filtered little cigars were the second-most used product behind cigarettes, with 3.8 percent of adults, or 9.3 million people, saying they used them.
Nearly 4 percent of adults use two or more tobacco products, with cigarettes and e-cigarettes representing the most common combination. It's unclear whether people are initially using both as part of the process to switch from cigarettes to e-cigarettes, but officials warn that people must fully switch in order to cut smoking risks.
Juul, the most popular e-cigarette on the market, was created to help smokers switch from cigarettes. While some adults are using the Juul devices to do just that, anecdotal evidence suggests many teens are also using the devices. Preliminary federal data show a 77 percent surge in high school students using e-cigarettes, figures that have prompted the Food and Drug Administration to label this an "epidemic."
The agency ordered five manufacturers — Juul, British American Tobacco's Vuse, Altria's MarkTen, Imperial Brands' Blu E-cigs and Japan Tobacco's Logic — to submit plans within 60 days on reducing teen use. The five companies represent about 97 percent of the e-cigarette market, according to the FDA.
Among adults, 2.8 percent used e-cigarettes last year, according to the CDC, down slightly from 3.2 percent in 2016. King cautions that this survey may not have captured how many adults are using Juul because the trend picked up in the later half of 2017 and the survey was conducted on a monthly basis.
He also worries that young adults are using these products more than older demographics even though they're less likely to smoke conventional cigarettes. For adults ages 18 to 24, 5.2 percent used e-cigarettes and 10.4 percent smoked cigarettes last year, according to the CDC.
"If e-cigarette use was responsible [for declines in cigarette use], you would expect to see a perfect correlation, but that's not what we're seeing," he said. "If anything, e-cigarettes have complicated the tobacco product landscape."
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