(Reuters Health) - - Teaching preschoolers to regulate their own behavior around food, combined with obesity prevention messages, did not reduce obesity or most obesity-related behaviors in a four-year U.S. trial.
But there are several potential reasons for the lack of effect, the researchers say, and they think more study is needed and clearly worth doing.
Almost a quarter of preschool-age children in the United States are overweight or obese, yet few obesity-prevention programs for this age group have been tested, Dr. Julie Lumeng of the Center for Human Growth and Development at University of Michigan in Ann Arbor and colleagues write in the journal Pediatrics.
They tested two interventions, alone and in combination, embedding the experiment within the federally-funded Head Start program for low-income children. During each of four academic years, classrooms were randomly allocated to one of three groups: Head Start alone (HS), Head Start plus the Preschool Obesity Prevention Series (HS+POPS), or Head Start plus POPS and the Incredible Years Series (HS+POPS+IYS).
POPS provides obesity prevention messages to preschoolers and their parents while IYS emphasizes positive behavioral management techniques and self-regulation.
Altogether the study involved 697 children around 4 years old, about half of them white, 30 percent black and 12 percent Hispanic. Some 16 percent to 17 percent of kids in the intervention groups were obese at the start while about 12 percent in the Head Start alone group were obese.
According to the researchers, HS+POPS+IYS improved the kids' teacher-reported self-regulation compared with HS+POPS and HS alone. But the programs failed to have significant effects on the prevalence of obesity, which was about 14 percent in both the HS+POPS+IYS and HS+POPS groups after the interventions. Obesity prevalence rose to about 13 percent among kids in the HS alone group.
The interventions also had no effect on other outcomes aside from sugar-sweetened beverage intake.
Lumeng told Reuters Health she really thought the intervention would be helpful. "Unfortunately, it was not.”
The study team writes that the intervention might not have been intense or long enough, or the assessment might not been long enough to reveal any effects on weight.
“It may be that the effects of promoting self-regulation to prevent obesity do not emerge until children are older,” Lumeng said by email. “For example, it may be that self-regulation of emotion and behavior may not impact food intake until children start to consciously attend more to their dietary intake, perhaps at ages 9 to 10 years or even a little older. When children are in the preschool age range, most of their food choices and dietary intake may still be primarily governed by parents and other adults,” she said.
More work is needed with more powerful and targeted behavioral approaches to self-regulation to adequately test whether improving children's self-regulation can prevent obesity, the researchers conclude.
“Stress has been linked to overeating and obesity in multiple studies," Lumeng noted. "Providing children tools to better regulate emotion and behavior in the context of stress may still be an important strategy. Future work may wish to more closely tailor these types of interventions specifically to emotional overeating or eating in response to stress.”
In a related editorial, two pediatricians write, “We live in an obesity-promoting environment, with ubiquitous highly palatable, energy-dense foods and easy access to reinforcing sedentary activities. To navigate through the environment unscathed by these dual threats, children need adult supervision and guidance and an ability to control temptation.”
Dr. Leonard Epstein and Dr. Stephanie Anzman-Frasca of the University of Buffalo in New York call the study "valuable," and write that while it didn't show improving self-regulation impacted on kids' weight, it's premature to call the case closed.
“This research offers the potential for collateral benefits, given that self-regulation is linked with multiple aspects of well-being over time,” they write.