The National Longitudinal Study of Adolescent Health, a school-based study of the health-related behaviors of adolescents, shows that parents who do not take care of their health are much more likely to have children who engage in unhealthy behaviors as well.
Specifically, the study showed that children of parents who smoke were around 50 percent more likely to have had sex -- and also more likely to have had sex by age 15. Teenagers whose parents engage in risky health behaviors -- defined in the report as "those behaviors that endanger one's physical being or health" -- were also more likely to smoke, drink, associate with peers who use drugs, and engage in delinquent behavior such as stealing and damaging property.
"Unsafe parental behaviors are not only associated with an increased likelihood that adolescents often practice these same behaviors, but also that they engage in analogous risky behaviors," says Esther I. Wilder, a professor of sociology at Lehman College who co-authored the study with Toni Terling Watt of Southwest Texas State University. "For example, adolescents whose parents smoke are not only more likely to smoke themselves, they are also more likely to drink, associate with friends who use substances, be sexually active, and/or have sex at early ages."
Of those who participated in the study -- which involved about 19,000 children in grades 7 through 12 -- 37 percent of girls and 39 percent of boys reported having had sex. However, Wilder and Watt found no correlation between unsafe parental behavior and whether the sexually active teen used contraceptives. Contraceptive use was more connected to the year in which the adolescent first had sex, with use being more likely after 1990 and the onset of the AIDS awareness movement.
The researchers also found that teenagers whose parents drink heavily tend to drink as well, and teen alcohol use is also closely linked to earlier sexual activity. For boys only, a parent's failure to wear a seat belt was also linked with a modest increase in the likelihood of adolescent sex.
The study showed different effects of parental supervision. Boys whose fathers are present at bedtime and when they leave for and return from school, for instance, were less likely to have had sex. The same was true for girls whose mothers were present at those times. However, the mother's presence had no impact on whether a boy was sexually active, and the father's presence had no bearing on a girl's likelihood to engage in sex.
Jennifer Lansford, a research scholar at Duke University's Center for Child and Family Policy, says the study's findings raise the question of through what mechanisms parents' own risky behaviors influence their adolescents' risky behaviors.
"Modeling particular behaviors is certainly one possibility," she says. "That explanation is clearest for the finding that parents who smoked and drank were more likely to have adolescents who also smoked and drank. Modeling is less likely to be the explanation for the finding that parents' smoking and drinking also increase adolescents' likelihood of engaging in sexual activity and decrease adolescents' likelihood of wearing a seat belt."
The National Longitudinal Study of Adolescent Health assesses a wide variety of health behaviors such as substance use, diet, physical disability and sexual behavior. According to Wilder, it also seeks to identify the social context of these behaviors and examine individual, family, peer, school and community characteristics as well.
The report will appear in the September issue of the Milbank Quarterly, a journal of public health and health care policy.
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