Vaping was marketed as an avenue to quit smoking cigarettes. But some smokers are now just doing both, CDC study finds.

• A new CDC study found that some people have taken to smoking both cigarettes and vapes.
• Vapes were previously pitched as a way to switch or quit smoking cigarettes.

Why would you "pick your poison" when you can enjoy both? Poor health outcomes. That's why.

The Centers for Disease Control and Prevention is now warning people who smoke both vapes and cigarettes about the negative health effects.

"Dual use of tobacco products is a health concern because it may result in greater exposure to toxins and worse respiratory outcomes than using either product alone," the CDC said in a newly released study on e-cigarette (or vape) use in adults in 2021.

Use of both products was highest in adults aged 18 to 44, the CDC found.

Vapes have previously been marketed as a way to quit smoking cigarettes. A past campaign for Juul, an e-cigarette company that was federally investigated for its marketing to young people, encouraged people to "make the switch" to e-cigarettes.

It seems some of those people just ended up smoking both.

"The Food and Drug Administration has not found any e-cigarette to be safe and effective in helping smokers quit. The fact is, e-cigarettes are tobacco products too," reads a statement from the American Lung Association, a nonprofit group.

Among all American adults, the CDC study found that 10.2% smoked only cigarettes, 3.2% smoked only e-cigarettes, and 1.3% smoked both.

E-cigarette use was greatest in young adults aged 18 to 24, where 11% reported using them. Most adults in that age category reported that they never smoked cigarettes.

"Despite this, the percentage of adults aged 18-24 who were dual users of e-cigarettes and cigarettes was similar to the percentage among adults aged 25-44 (1.8% compared with 2.0%)," the study found.

Meanwhile, adults aged 45 and over largely preferred cigarettes only, reporting the lowest percentages of e-cigarette use or dual use.