If you think just one cigarette a day is harmless, a new study might make you kick the habit for good.

The study, published in the American Heart Association Journal, Circulation: Arrhythmia & Electrophysiology, shows that women who smoke anywhere from one to 14 cigarettes a day have nearly two times the risk of sudden cardiac death than non-smoking women.

That may be a scary stat, but it gets worse.

"Sudden cardiac death is often the first sign of heart disease among women, so lifestyle changes that reduce that risk are particularly important," the study's lead author, Roopinder K. Sandhu, said in a press release.

In other words, you likely won’t know you have heart disease—until it’s too late.

Luckily, there is one way to drastically reduce your risk: Quit smoking.

According to the study, women without heart disease who quit smoking will see an immediate reduction in sudden cardiac death risk. Those who already have heart disease can reduce their risk to that of a non-smoker within 15 years of quitting.

“Until now, we didn't know how the quantity and duration of smoking effected the risk among apparently healthy women,” says Sandhu.

Well, now we do—so before you think having “just one” won’t make a difference, decide whether it’s worth the risk.

What do you think? Will you kick your casual smoking habit after learning how harmful it can be?

-Katharine Watts, Associate Web Editor

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