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Smoking Cessation Health Center

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E-Cigarettes: What the Research Shows

E-Cigarettes vs. Tobacco Cigarettes

Tobacco contributes to 5 million deaths worldwide a year. For centuries, cigarettes have remained basically the same: tobacco rolled in paper. What makes them so deadly are the estimated 4,000 chemicals they give off when lit. Some of those chemicals, like arsenic, formaldehyde, and lead, can cause cancer and a long list of other deadly diseases.

An e-cigarette is a battery-powered tube about the size and shape of a cigarette. A heating device warms a liquid inside the cartridge, creating a vapor you breathe in. Puffing on an e-cigarette is called "vaping" instead of "smoking." E-cigarettes also make chemicals, but in much smaller numbers and amounts than tobacco cigarettes.

What’s in E-Cigarettes?

The nicotine in e-cigarettes goes to your brain quickly. It can cause a brief feeling of relaxation and can lift your mood. As the nicotine leaves your system, your body craves another cigarette. Some research links nicotine to a higher risk of heart disease.

While the amount of nicotine in e-cigarettes is far lower than in regular cigarettes, the doses can vary greatly by e-cig brand.

The other main chemicals in e-cigarettes are propylene glycol and vegetable glycerin. They are used either separately or together as liquids to make the vapor.

Propylene glycol is a food additive and an ingredient in the fog machines used in clubs and theater shows. It has been through a lot of testing, and the FDA considers it safe for use in food and medicine. It's an ingredient in many food flavorings, toothpastes, and cough syrups. It has been linked to minor skin and lung irritation.

The FDA also considers vegetable glycerin safe for people to use, but there's not a lot of research to confirm its effects on health.

There’s also a lack of research into what's produced when you "light up." The heat can create potentially harmful chemicals, although in amounts 9 to 450 times lower than in real cigarettes. The evidence isn't clear on the health effects of these lower amounts of chemicals.

Also worrisome is the rainbow of flavors added to make e-cigarettes taste like everything from mint to bubblegum. Although the FDA says these additives are safe enough to be eaten in food, "we don't have enough data showing the potential risk from inhaling these flavors," says Maciej Goniewicz, PhD, PharmD. He's an assistant professor at Roswell Park Cancer Institute in Buffalo, N.Y.

The sheer number of e-cig varieties on the market adds to the problem. "There are different models, different types, different brands," Goniewicz says.

The chemicals in them can vary, too. That makes it hard to draw any conclusions about their safety.

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