Want to slap your teenager for smoking pot? That would make his drug use one and a half times more likely.

Hitting Your Kids Increases Their Risk of Mental Illness

What qualifies as appropriate punishment is a hot-button topic among parents. The American Academy of Pediatrics opposes corporal punishment, but studies have shown that up to 80% of parents report that they rely on it to some extent. What constitutes physical punishment is also wide-ranging: everything from a light slap on the hand to an all-out whipping with a belt or a paddle.

“In the general population, there is a belief that physical punishment is O.K. as long as you’re not doing it in anger and you’re a warm and loving parent,” says Tracie Afifi, the study’s author and an assistant professor in the Department of Community Health Sciences at the University of Manitoba in Canada. “But there’s no data supporting that.”

Afifi and colleagues decided to examine five forms of physical punishment — pushing, grabbing, shoving, slapping and hitting — that took place in the absence of even more severe acts of abuse or neglect such as punching, burning, physical neglect or sexual abuse.

She did not examine spanking because it’s not easy to define: what’s considered spanking varies from parent to parent. But, she says, “a push is a push, and a grab is a grab.”

In the study, researchers analyzed more than 20,000 people in the U.S. who were age 20 or older: 1,258 who had experienced pushing, grabbing, shoving, slapping and hitting sometimes or very often, and 19,349 who reported they had experienced it rarely or never. They adjusted results for gender, race, marital status, education and a history of family dysfunction; if the person’s parents had drug problems or were hospitalized for mental illness, that could have affected their use of physical punishment.

Across the board, people who’d experienced physical punishment were more likely to experience nearly every type of mental illness examined. Their risk of mood disorders, including depression and mania, was 1.5 times greater than people who hadn’t been slapped or grabbed. The risk of depression alone was 1.4 times greater, which was the same rate for anxiety. People who’d been physically punished were 1.6 times more likely to abuse alcohol, and 1.5 times more likely to abuse drugs.

“There’s going to be lot of people that think that a parent absolutely needs to use physical force to raise a compliant child,” says Afifi. “It’s pretty well established that physical abuse has a negative impact on mental health, but this is showing the same effect even when you look at milder forms of physical force. This is saying that physical punishment should not be used on children of any age.”

“Other studies have shown corporal punishment in childhood carries over to adulthood in terms of aggression, so there’s no reason why it wouldn’t in the area of mental health.”