OK, this one may be a bit of a no-brainer, but I'm still glad that someone has finally tested the theory.

A new study from researchers at Concordia and University of Montreal found that tweens who repeatedly see a trusted adult such as a parent, sibling, friend or neighbor smoking cigarettes are more likely to start smoking themselves. You don't say? But still, I have witnessed countless adults smoking cigarettes in front of young children who think they can negate their behavior by warning kids about the dangers of smoking — all while puffing away on their Marlboros. Don't these adults realize that their words mean nothing? Only their actions are making an impression. And now this study proves it.

For the study, researchers questioned 327 11- to 13-year-olds enrolled in public schools about their smoking habits, the number of smokers in their home and the situations where they observed smoking. Each child also provided a saliva sample from which the researchers were able to measure their exposure to secondhand smoke.

Parents may already be aware that secondhand smoke is harmful to kids, but they may not realize that secondhand smoke exposure could possibly trigger addiction in the brain — before kids actually start smoking themselves. 

So whether you're in the car, in the living room, or on the front porch — put that cigarette out! You owe it to your kids to curb the habit if it keeps them from seeing their health and their money go up in smoke.

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