Low inhibitory control and restrictive feeding practices predict weight outcomes

Abstract

Objective: A priority for research is to identify individuals early in development who are particularly susceptible to weight gain in the current, obesogenic environment. This longitudinal study investigated whether early individual differences in inhibitory control, an aspect of temperament, predicted weight outcomes and whether parents' restrictive feeding practices moderated this relation.

Study design: Participants included 197 non-Hispanic white girls and their parents; families were assessed when girls were 5, 7, 9, 11, 13, and 15 years old. Measures included mothers' reports of girls' inhibitory control levels, girls' reports of parental restriction in feeding, girls' body mass indexes (BMIs), and parents' BMIs, education, and income.

Results: Girls with lower inhibitory control at age 7 had higher concurrent BMIs, greater weight gain, higher BMIs at all subsequent time points, and were 1.95 times more likely to be overweight at age 15. Girls who perceived higher parental restriction exhibited the strongest inverse relation between inhibitory control and weight status.

Conclusion: Variability in inhibitory control could help identify individuals who are predisposed to obesity risk; the current findings also highlight the importance of parenting practices as potentially modifiable factors that exacerbate or attenuate this risk.

Figure 1

BMI over time in girls with low and high inhibitory control. Girls with lower inhibitory control tended to have a higher BMI at each time point, as well as a faster rate of BMI increase over time. Although the corresponding analyses reported in this manuscript were conducted using a continuous measure of inhibitory control, the categorical comparisons depicted in this figure were also statistically significant, including the comparisons between low and high inhibitory control groups at each time point (represented by the asterisks, all p<.05), as well as the comparison of the slopes of the two lines (p<.05; low inhibitory control group n=41; high inhibitory control group n=151).

Figure 2

Average BMI change by inhibitory control and restriction groups, with corresponding BMI percentiles. Girls with lower inhibitory control and higher parental restrictive feeding tended to show the most weight gain over time and the highest BMIs at study termination. This group’s average BMI crosses into the overweight range over time (greater than the 85^th percentile for age and sex; CDC Growth Charts). This group’s BMI and BMI change were significantly different from those of girls with higher inhibitory control (the two gray lines). Different subscripts to the right of the lines indicate statistically significant differences between groups on average BMI change (slope) and age 15 BMI (p<.05; low IC/low res n=15; low IC/high res n=21; high IC/low res n=69; high IC/high res restriction n=62).