The study, published in the journal JAMA Paediatrics, examined the role of frequent family meals in reducing the impacts of online bullying on adolescent mental health.
The researchers surveyed 20,385 adolescents in the state of Wisconsin.
They measured exposures to cyberbullying and traditional face-to-face bullying and a wide range of mental health issues including depression, anxiety, substance use, self-harm, suicidal thoughts, and suicidal attempts.
Prof Elgar, whose research centres on social inequalities in health and family influences on child mental health, said: "We found that emotional, behavioural, and substance use problems are 2.6 to 4.5 times more common among victims of cyberbullying.
"And these impacts are not due to face-to-face bullying; they are specific to cyberbullying."
The researchers found that cyberbullying victimisation relates more strongly to these problems in adolescents that have fewer family dinners, which suggests that family contact and communication reduces some of the distressing effects of cyberbullying.
Prof Elgar said: "The results are promising, but we do not want to oversimplify what we observed.
"Many adolescents do not have regular family meals but receive support in other ways, like shared breakfasts, or the morning school run."
Prof Elgar also said that parental involvement and supervision may go a long way to helping victims of cyberbullying, adding: "Checking in with teens about their online lives may give them tools to manage online harassment or bullying that can easily go undetected."