A new study shows spanking your child can be more damaging to them than first thought.
Scientists at Columbia Unversity School of Social Work looked at nearly 2,000 children from 20 large cities in the United States. They found spanking is still very common.
A third of fathers, and half of mothers were spanking their children by the time the kids were five and that was only looking at spanking in the past month.
Study Author Dr. Michael McKenzie says, "we found that children who were spanked by fathers at high levels showed decreases in verbal capacity by age 9."
Dr McKenzie says children who were spanked at least twice a week by their mother at age 3 or 5 were also more likely to break rules and act aggressively.
Critics say one issue with the study is that researchers did not define spanking which can range from a swatting to more forcefuil hitting.