Parental smoking affects immune system development

Even post-natally, parental smoking seems to result in a depression of interferon {gamma} production at age 11, according to a study published in the June 2008 issue of Pediatrics. Interferon {gamma} is involved in "pathogen recognition, antiviral response, and activation of immune effector functions," and deficits in its production may leave kids vulnerable to recurring infections. You can read more here.