SYDNEY - Children with fat fathers are more likely to be obese by age of eight or nine than those with healthy weight fathers, a new study by researchers at Australia's University of Newcastle found on Thursday.

Researchers at the University of Newcastle found that children who had an overweight or obese dad were four times more likely to follow in their father's footsteps than those with a dad in the healthy weight range.

They also found in the study that only having an obese or overweight mum in the family did not have the same effect.

Lead researcher Emily Freeman said it was still unknown why overweight dads had such a significant effect on their children's weights.

The researchers conducted their study using data collected from 3000 Australian families between 2004 and 2008 for a longitudinal study.

They looked at the weights of children when they were aged four to five and then again when they turned eight and nine years old.

According to Freeman, around 25 percent of Australian children are overweight or obese.

She said helping fat dads lose weight could make a difference to the youngsters.