Smacking naughty toddlers may cause them to become aggressive teenagers, new research suggests.
Toddlers who are severely punished are more likely to be aggressive at 10 to 11 years old, a study found.
Such children are also less likely to show positive behaviors, such as helping others, the research adds.
The researchers warn that how parents treat their children at a young age can have a long-lasting impact on youngsters' behavior.
They advise grown-ups encourage children to self-regulate their emotions from an early age.
Smacking naughty toddlers may cause them to become aggressive teenagers (stock)
Watching television for three or more hours a day may increase a child's risk of diabetes, research suggested last month.
Children who spend at least three hours in front of a screen are heavier and have greater insulin resistance, a study found. Both of these are risk factors for type 2 diabetes.
Such youngsters also produce impaired amounts of the hormone leptin, the research adds. Leptin is involved in regulating appetite.
These results remained even after the study's participant's activity levels were taken into account, the study found.
Study author Dr Claire Nightingale from St George's, University of London, said: 'Our findings suggest that reducing screen time may