According to a decade long study from the National Center on Addiction and Substance Abuse (CASA), teens who regularly have meals with their family are less likely to get into fights, think about suicide, smoke, drink, use drugs, and are more likely to have later initiation of sexual activity, and better academic performance than teens who do not.
Rutgers University anthropologist Robin Fox emphasizes the importance of positive intention in family meals. "It's like the American Indians. When they killed a deer, they said a prayer over it," says Fox. "That is civilization. It is an act of politeness over food. Fast food has killed this. We have reduced eating to sitting alone and shoveling it in. There is no ceremony in it."
The CASA study also showed that eating with parents is also an important factor for the nutrition and eating habits of adolescents, with research showing that family meals and parental presence at meals is associated with higher intake of fruits, vegetables, and dairy products. http://www.organicconsumers.org/2006/article_752.cfm