Researchers found a link between a genetic predisposition to obesity and a larger appetite.
Researchers analyzed at how weight gain was related to lower satiety responsiveness ("a reduced urge to eat in response to internal 'fullness' signals") and higher food responsiveness ("an increased urge to eat in response to the sight or smell of nice food"), a University College London news release reported.
The researchers looked at non-identical, same-sex twins with different satiety responsiveness (SR) and food responsiveness (FR); the study subjects were followed between the ages of three and 15 months.
The researchers found the twin with the higher food response was about1.4 pounds heavier at the age of six months than their twin with a lower response; but the age of 15 months they were 2.1 pounds heavier. The less satiety responsive twin was 1.4 pounds heavier than their co-twin at six months and two pounds at 15 months.
"Obesity is a major issue in child health" Professor Jane Wardle, lead author of the study from the UCL Health Behaviour Research Centre said in the news release. "Identifying factors that promote or protect against weight gain could help identify targets for obesity intervention and prevention in future. These findings are extremely powerful because we were comparing children of the same age and same sex growing up in the same family in order to reveal the role that appetite plays in infant growth.
"It might make life easy to have a baby with a hearty appetite, but as she grows up, parents may need to be alert for tendencies to be somewhat over-responsive to food cues in the environment, or somewhat unresponsive to fullness. This [behavior] could put her at risk of gaining weight faster than is good for her," she said.
The research team also looked at 2,258 10-year-olds and calculated each subject's polygenic obesity risk score (PRS) that calculated their genetic susceptibility of obesity. Higher PRS scores were linked with a higher genetic predisposition to obesity.
"As expected, we found that children with a higher PRS score (more obesity-risk' genetic variants) were likely to have larger BMI and waist circumference," Doctor Clare Llewellyn, lead author from the UCL Health Behaviour Research Centre said in the news release. "But more importantly, we also found that these children were more likely to have low satiety responsiveness.
"This suggests that satiety sensitivity could be targeted for pharmacological and behavioural interventions, to prevent or treat obesity. For example, children with lower satiety sensitivity could be taught techniques that might improve their fullness signals when eating, such as slowing their eating speed. Another approach might be to provide better advice to parents and children about appropriate portion sizes, limiting access to 'second helpings' and ensuring tempting treats are out of sight between meals," she said.
