An overweight mother, watching TV and being a girl increase your odds of being an obese child.

A study from The University of Auckland, published in the Archives of Disease in Childhood, monitored the weight of 571 New Zealand children of European heritage from birth to age 7. The research found having a mother who was overweight or obese, being a girl, and spending a lot of time in front of the TV were all independently associated with the chances of becoming obese.

Other factors include rapidly gaining weight in early childhood and having rapid growth spurts.

Percentage body fat, a reliable indicator of overweight and obesity, was calculated at the age of 3½ and 7 years, as well as TV viewing time and the amount of physical activity they took part in at the age of 7.

Children who had acquired a high percentage body fat by the age of 3½ were significantly more likely to be obese at the age of 7 than those with low percentage body fat. Children whose mothers were overweight or obese had around 4% more body fat than those whose mothers were of normal weight. Children who spent more than 3 hours a day in front of the TV had 5% more body fat than those who watched TV for less than an hour.

"Children with overweight mothers tend to be overweight themselves at a very early age," says Professor Ed Mitchell of the Faculty of Medical and Health Sciences. "It is not clear if genes, exposure to specific factors during pregnancy, or shared lifestyle factors are to blame, but children seem to start on the trajectory to overweight and obesity early in life. Consequently, we need to put counter measures in place as early as possible to keep our children healthy."