A new study shows that kids whose dads smoked—even before their child was conceived—are more likely to have asthma.
Young man smoking a cigarette
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Hey guys: you might want to jettison those cigarettes if you plan to have kids one day. Because as it turns out, it's not just a mom-to-be's smoking habit that's bad for your future offspring.

According to a new Norwegian study published in the International Journal of Epidemiology, kids with a father who smoked prior to conception are three times more likely to have early-onset asthma than children of fathers who never lit up.

That's pretty major—and even more surprising was the finding that the kids most in jeopardy of developing early-onset asthma were the ones whose dads started smoking back when they were just teenagers.

"The greatest increased risk for their children having asthma was found for fathers having their smoking debut before age 15," said Cecilie Svanes, a study author and a professor at the Centre for International Health, Department of Global Public Health and Primary Care, at the University of Bergen, Norway.

Translation: a dad-to-be's health habits before a pregnancy (way before!) matter just as much as mom's during it!

Speaking of which... the research found more asthma in offspring if the mother smoked around pregnancy, which is consistent with previous studies. "However, no effect of maternal smoking only prior to conception was identified," said Svanes, who added that the difference from father's smoking suggests effects through male sperm cells.

"Smoking is known to cause genetic and epigenetic damage to spermatozoa, which are transmissible to offspring and have the potential to induce developmental abnormalities," she explained. "There is growing evidence from animal studies for so called epigenetic programming, a mechanism whereby the father's environment before conception could impact on the health of future generations."

Just another reason we need to educate our kids about the dangers of smoking sooner rather than later.

If you a dad or hopeful dad who needs help kicking the habit, check out our tips to quit here.

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Hollee Actman Becker is a freelance writer, blogger, and a mom. Check out her website holleeactmanbecker.com for more, and then follow her on Twitter at @holleewoodworld.