Obesity is directly related to variations in appetite – apparent from the first weeks of a baby’s life, a conference has been told.
From early life, there are profound variations in babies’ appetites, largely explained by genetic factors, the conference organised by Safefood heard.
These differences in appetite are driving early weight gain "quite potently", according to Dr Clare Llewellyn of University College London.
Inherited differences in appetite predispose some people to obesity, making them more susceptible to obesity than others, she said.
“Can this be changed? Yes, if you change the environment [in which food is consumed], you change the way people respond to the environment.”
Almost 100 genetic variants are robustly associated with body mass index in adults and children, and genes partly influence weight through their influence on appetite, she pointed out.
Environmental factors, such as family influences on children's eating behaviour, help to explain increased obesity, as well as genetic factors, according to Dr Faye Powell of the University of Bedfordshire.
Parental choices
This is because parental choices at home influence children’s emerging ability to self-regulate their energy intakes, she told the conference on the role of appetite in obesity.
This wasn’t just about the food served but was also linked to feeding practices.
Where parents overeat due to emotions, for example, children tend to do the same. Parents’ attempts to modify behaviour by, for example, pressurising children to consume more of certain foods can be detrimental.
Dr Powell said this practice was linked to fussy eating by the child and lower fruit and vegetable intake, as well as weight gain.
Availability of and exposure to food can be used to influence behaviour, she said, and encouragement and positive reinforcement works better than pressure. Involving children in food-related activities had also been shown to have positive results.
Family mealtimes offer parents the opportunity to act as role models but it was important not just to eat together but for all family members to eat the same food.
Prof Kees de Graaf, of Wageningen University in the Netherlands, said the speed at which food was consumed affected consumption.
We consume apple juice 10 times as fast as apples, he pointed out.
Eating soft, energy-dense foods leads to over-consumption and obesity, he said.
It wasn’t about sugar or fat per se, but about texture and energy density.
