Parents who hit their children to discipline them could be increasing their risk of mental illness in adulthood, according to a new Canadian study.
Researchers from the University of Manitoba studied data collected from more than 34,600 American adults who were surveyed in 2004 and 2005.
Participants were asked: "As a child, how often were you ever pushed, grabbed, shoved, slapped or hit by your parents or any adult living in your house?"
About 6 percent of respondents said they had been physically punished sometimes, fairly often or very often as a child but weren't abused in other ways.
The researchers found those people were 59 percent more likely to have alcohol problems, 41 percent more likely to have depression and 24 percent more likely to have a panic disorder than those who weren't punished physically.
The researchers said 2 to 7 percent of adult mental disorders occur as a result of physical punishment during childhood.
But the researchers said there were limitations to their study, because it required adults to recall memories of their childhood, and those memories may not be entirely correct.
The study did not include people who were maltreated as children and suffered such things as physical and sexual abuse or emotional neglect.
Clinical psychologist Sally-Anne McCormack from Parentsonline.com.au told ninemsn she's not surprised to hear this study confirms smacking regularly can cause psychological damage.
"Smacking as a strategy is going to cause various mental health issues for a child because that's all that they ever see," she said.
"If someone is regularly smacked or hit, it's seen as a punishment so a child will have a reduced self-esteem and self-concept, which does put them at risk of mental health issues like depression and anxiety."
Instead, she recommends more placid approaches to correcting misbehaviour.
"There's a million different strategies to use instead of smacking distraction, veering them in a different direction and spending time with them all work," McCormack said.
"One of the mistakes parents make is to tell them what not to do rather than tell them what to do. So instruct them and give them ideas of what they can do instead [of being naughty]."