We all know that cigarette smoke is bad for children, but new research has suggested that your habit could still affect your kids' health even if you never do it in their presence. According to the research, mice born to fathers who were exposed to nicotine inherited enhanced chemical tolerance and drug clearance abilities. If the same proves true in humans, it could mean that children of smokers may have enhanced tolerance for certain chemical procedures, such as chemotherapy.

The study found that mice with fathers exposed to the nicotine equivalent of a habitual smoker inherited epigenetic changes that gave them higher chemical tolerance and allowed them to clear drugs from their system more efficiently, possibly by helping their livers metabolize drugs better. In addition to nicotine, these mice also had enhanced protection from the toxicity of cocaine. 

Read: Secondhand Smoke Exposure In Early Childhood May Increase Risk Of Baby Tooth Decay

"This demonstrates that 'dad' paints with very broad brush strokes. Fathers exposed to nicotine do not specifically program changes in nicotine receptors in their children, as these children are broadly resistant to multiple toxins," said study author Oliver J. Rando in a recent statement.

Although it's too soon to say if the same changes would be seen in human children with smoker dads, the research shows us several possibilities — it could lead to various health effects, from reducing their sensitivity to chemotherapy to increasing the likelihood they too will smoke.

"There are obvious reasons to be interested in whether this type of effect also happens in human beings, but given the differences between mice and humans in their metabolism of nicotine, it will need to be tested rigorously in future studies of human populations," added Rando in a statement.

Children exposed to secondhand smoke are at increased risk for a host of nasty health problems, including tooth decay. A 2015 study found children exposed to secondhand smoke were twice as likely to experience baby tooth decay

In addition, a mother’s smoking during pregnancy can even affect the developing child’s brain and increase their risk of developing schizophrenia. A 2016 study found that higher maternal nicotine levels in a mother’s blood were linked to a higher risk of schizophrenia among their children. The precise cause for this relationship is not yet clear, but it's one more reason for expectant parents to kick the habit. 

Source: Vallaster MP, Kukreja S, Bing XY, et al. Paternal nicotine exposure alters hepatic xenobiotic metabolism in offspring. eLife . 2017

See Also:

Kids Drink And Smoke Even Younger When Parents Are Absent

Smoking During Pregnancy Could Increase Risk Of Your Children Having Schizophrenia