Reprinted from Eating Disorders Review
September/October Volume 26, Number 5
Q. I’ve been reading that more than one-third of American children are either overweight or obese. I know genetics plays a role, but what specific behaviors place some young children at greater risk for obesity than others? (L.B., Houston)
A. Two psychologists, Drs. Silje Steinsbekk and Lars Wichstrøm, at the Norwegian University of Science and Technology, Trondheim, recently addressed this question. The clinicians followed changes in body mass index (BMI, kg/m2) among 995 children in Trondheim, Norway, from 4 to 8 years of age. Then they analyzed appetite level, physical activity, and television-watching time among the children at three time points: at 4, 6, and 8 years of age. All 995 children participated at 4 years, and 760 and 687 of the children took part in the assessments at 6 and 8 years, respectively.
The children’s weights and heights were measured at ages 4, 6, and 8, and BMI was calculated. The Children’s Eating Behavior Questionnaire was used to assess appetite traits at age 6. Physical activity was measured at age 6 using an accelerometer, and daily mean television watching time was gathered by interviewing the parents when their child was 6. Parents’ occupations were also recorded.
It turned out that food responsiveness was highly important. Children with high food responsiveness at age 6 had a steeper increase in BMI from age 6 to age 8. Also, greater increase in BMI from age 4 to age 6 predicted higher food responsiveness.
Thus, high food responsiveness predicts more rapid weight gain in children. However, neither satiety responsiveness nor slowness in eating affected BMI, suggesting that appetite traits previously thought to be important may play a smaller role or any role at all in the development of obesity as a child ages. Interestingly, physical activity and TV-watching time were not related to BMI.
There were some limitations to the study as well.. First, while the Children’s Eating Behavior Questionnaire has shown good validity, it has not been validated in a Norwegian sample. Another possible element was the parents’ subjective evaluation of their child’s appetite traits, which might reflect social desirability rather than a factual and nonbiased report. In addition, different methods were used to measure weight and height at the three age points. The authors also added that the increased risk of obesity is related to an early adiposity rebound, somewhere around the age of 5 years.
Drs. Steinsbekk and Wichstrøm concluded that children whose eating is markedly triggered by the sight and smell of food show prospective increased weight gain. Excess weight and weight gain also predict increased food-approaching behavior, according to the authors.
So, children whose eating is strongly driven by the sight and smell of food are at risk of weight gain. Perhaps this trait is one of the ways that genes place a child at risk for obesity (or for disordered eating?).