Culturally we pretty much inhale our food. We eat at our desks; we gobble standing up; we down food mindlessly in the car and while multitasking. Such practices are not only unhealthy for adults; they also send kids an unhealthy message that negates the importance of appreciating food and enjoying its social aspects. Eating fast literally drowns out the critical satiety signal that would tell kids to stop eating.
Researchers reporting in the online edition of Pediatric Obesity (doi: 10.1111/ijpo.12091) concluded that waiting 30 seconds between bites of food allows children to realize they’re no longer hungry before they overeat—preventing excessive weight gain.
The study’s goal was to minimize the amount of food children ate before their stomachs told their brains they were no longer hungry—the so-called “satiety reflex.” That signal usually takes about 15 minutes to kick in. But in modern society whole meals can be consumed in much less time, the researchers said.
The study monitored the eating habits of 54 children aged 10-14 in Durango, Mexico, for a year. They were divided into two groups: those who ate slowly, as instructed by researchers (compliant group), and those who didn’t (noncompliant group). Students with similar demographics served as a control group.
Compelling results showed that weight decreased among compliant students by 2% ± 5.7% in 6 months and by 3.4% ± 4.8% in 1 year. By contrast, weight increased among noncompliant students by 5.8% ± 4.4% in 6 months and by 12.6% ± 8.3% in a year. In the control group, weight increased by 8.2% ± 6.5% in 1 year.
Unlike most diets, the slow-eating approach has the advantage of being sustainable over the long term because it doesn’t require you to change what you eat on a daily basis, said Geert Schmid-Schonbein, PhD, a study co-author and bioengineering professor at the Jacobs School of Engineering, University of California, San Diego. Slow eating doesn’t deprive you of your favorite foods, and it can be applied in any cultural and ethnic context.
“You can adopt this slow eating approach for yourself and keep it up for the rest of your life,” Schmid-Schonbein suggested. “You can teach this approach to your children, and they can teach it to their children in turn.”
To avoid overeating, students were instructed to chew each bite for 30 seconds before taking the next bite. This gave them time to realize that they were no longer hungry and to stop eating. To make sure they waited the right amount of time, they all received small hourglasses that emptied in 30 seconds. Researchers instructed them to take a bite, flip the hourglass and not take another bite until the hourglass ran empty. Researchers also instructed the students to drink a glass of water before each meal and avoid snacking between meals.
The results were so promising that the Mexican states of Michoacán, Yucatán and Veracruz have invited researchers to take the study’s methods into schools.
The study authors would like to conduct further research with a larger sample size, drawn from both Mexico and Southern California, targeting the region’s large Hispanic population. The authors also noted that this approach is untested in adults.