London, Jul 11 (IANS): Did you know even your mood and attitude during pregnancy can have an effect on the body weight of your children when they grow up? A new study has found that teenagers are less likely to be overweight if their mother or father had a positive attitude during pregnancy.

Negative attitude, or a lack of self-belief in your ability to bring in changes to your lifestyle through your actions, may be associated with unhealthy weight gain in your children during teenage years, suggests the study published in the International Journal of Obesity.

"We've been able to show that a lack of self-belief in a parent's ability to influence change by healthy eating, stopping smoking or breast feeding is a contributing factor to their child being overweight by the time they are 15," said lead study author Jean Golding, Professor at University of Bristol in Britain.

For the study, the researchers analysed responses from 7,000 parents about their personality, mood and attitude during pregnancy.

Similar answers from their children at age of eight and the child's fat mass measurement up to the age of 17 were also analysed.

The results showed that a mother's psychological background during pregnancy is a factor associated with teenage weight gain.

The study examined a personality attribute known as the Locus of Control. It is a psychological measure for an individual's attitudes towards their lifestyle and a belief in being able to change outcomes, such as health, through their own actions.

Someone with an external Locus of Control would feel that there is little point in making an effort as what happens to them is due to luck and circumstance.

The researchers found that teenagers at age 15 had an excess weight of actual fat to the extent of 1.7 kg if their mothers did not think their actions would make a difference and held a laissez-faire attitude.

If their fathers had this attitude the excess weight of fat was 1.49 kg and if the child later thought this way the excess was 1.5 kg, the study said.

"This is important research for health campaigners looking to change behaviours and the next steps should be looking at the differences between parents who managed to change their Locus of Control compared to those who did not change," Golding added.