Few would disagree that sitting down to dinner together as a family is a good thing. It can help families eat healthier, encourage meaningful conversation and according to some addiction researchers, it even keeps kids from using drugs.
Indeed, dining together has been so widely touted as a critical anti-drug measure that the fourth Monday in September has been designated "Family Day — A Day to Eat Dinner with Your Children" and is observed in all 50 states. In 2009, President Barack Obama even recognized Family Day in an official proclamation.
“America’s drug problem is not going to be solved in courtrooms or legislative hearing rooms by judges and politicians. It will be solved in living rooms and dining rooms and across kitchen tables — by parents and families,” declares Joseph Califano, the founder of the National Center on Addiction and Substance Abuse, which created Family Day, on the center's website.
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Problem is, the data don't clearly show that family dinners alone are what matter. According to a large new study published in the Journal of Marriage and Family, teens who dine together with their families aren't any less likely to use drugs or become delinquent in the long run, compared with teens who eat fewer family dinners. The reason previous studies found such a strong association, the researchers say, is that they didn't last long enough to gauge the full effect or they failed to control for family-related factors other than dinner that can influence children's drug and delinquency risk.
For instance, consider the kinds of families who are least likely to share meals regularly: those with actively addicted or alcoholic parents, families with disengaged parents, those in which parents are in the midst of intense family conflict, and families with demanding jobs or economic hardships that simply don’t permit parents and kids to spend much time together. All of these factors are independently linked with problematic teen behavior.
In contrast, parents who have high-quality relationships with their children, those who are able to monitor their kids' activities and who spend time more time with them on things like homework and outings are also those who are more likely to eat dinner with their children, says Kelly Musick, an associate professor of policy analysis at Cornell University and co-author of the new study.
“The ability to manage a regular family dinner is in part facilitated by family resources, such as time and money, and in part a proxy for other family characteristics, including closeness, communication and time together,” says Musick.
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In her new study, which was the first to follow teens into adulthood, Musick says that "controlling for the quality of family relationships in particular explained much of the family dinner’s association with teen depressive symptoms, substance use and delinquency.”
The study relied on data from the National Longitudinal Survey of Adolescent Health, which includes nearly 18,000 teens who were first surveyed in grades 7-12 in 1994-95, then queried again in 1996, and again for a third time in 2001-03.
When the researchers looked at teens at a single point in time, they found that those who were eating five or more dinners a week with their families were 18% less likely to use drugs than teens who ate with their families on two or fewer evenings. But after controlling for factors like socioeconomic status and the quality of parent-child relationships, that effect was halved to 9%.
And when the authors looked at changes in dinnertime habits over the years, they found that no significant effect on drug use remained after accounting for other factors. Not surprisingly, teens who had better relationships with their families and fewer arguments with parents — factors that were closely tied to the frequency of family dinners — tended to be less likely to use drugs or to be delinquent.
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Interestingly, however, the analysis also found that family meals were associated with significantly lower rates of depressive symptoms in teens, a finding that persisted, even after researchers controlled for other factors. The more dinners teens ate at home, the less depressed they were: kids who ate at home seven nights a week had 15% fewer symptoms of depression than those who dined with their families only twice a week. That’s a large effect, comparable to the difference in depressive symptoms measured in teens living in single-parent homes, compared with those being raised by two biological parents.
Still, even that positive effect didn’t outlast adolescence. “Following teens even further into young adulthood, we found no direct link between family dinners and young adult outcomes,” says Musick. “It could be that the effects of family dinners work indirectly through earlier contributions to well-being, but taking those earlier contributions into account, we found no direct, lasting effect of family dinners into young adulthood.”
Moreover, the study couldn’t determine which came first: drugs or family dinners. That is, do teens who use drugs or feel depressed avoid family dinners to begin with, or does having dinner together actually prevent such problems? Also, because the researchers measured drug use, rather than abuse or addiction, they could not determine whether family dinners were preventing short-term experimentation that teens would have eventually outgrown or genuine drug problems. About two thirds of the teens in the study said they had tried drugs, including alcohol, but previous research shows that fewer than 15% of drug users typically become addicted.
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“We don’t dismiss the possibility that family meals matter for children, but we are much more cautious than prior research about the unique contributions of family meals to child well-being,” says Musick, noting that there is still much that is unknown about the issue.
For instance, are family dinners always a good thing? Musick is now studying whether eating together may be less helpful — or even harmful — in families who are in conflict or have otherwise troubled relationships. “Our preliminary findings suggest that dinners are more strongly associated with child well-being in families with high-quality relationships,” Musick says. “It’s questionable, then, whether sending a distant, distracted or high-conflict family to the table would do any good for the children involved.”
Maia Szalavitz is a health writer at TIME.com. Find her on Twitter at @maiasz. You can also continue the discussion on TIME Healthland’s Facebook page and on Twitter at @TIMEHealthland.