Kids who are given larger bowls will ask for more cereal than when they're given smaller bowls, and will more than likely overeat or waste the excess food, according to a new study.
Research has show that adults serve themselves bigger portions when they're given bigger plates, by as much as 22 percent, said Brian Wansink, a professor of consumer behavior at the Cornell Food and Brand Lab at Cornell University.
Wansink and colleagues wanted to see if bowl size had any influence on the amount of cereal requested by young children, so they carried out two separate studies. The results of both were published in The Journal of Pediatrics.
The first study involved 69 preschoolers and took place at Cornell, in Ithaca, New York. Each child was randomly selected to receive either a small eight-ounce bowl or a large 16-ounce bowl. Researchers asked the children how much cereal they wanted for a morning snack and then poured dry cereal into the bowls until the kids said to stop.
In general, the children who had the larger bowls asked for 87 percent more cereal than the children who were given the small bowls. The results were about the same for both boys and girls and for kids of any weight or body mass index.
The children were not allowed to eat the cereal so it isn't known how much would have gone to waste.
The second study involved 18 elementary school children attending a summer camp, who were randomly assigned either small eight-ounce bowls or larger 16-ounce bowls for breakfast.
Cafeteria workers asked the children how much cereal and milk they wanted. The workers poured the cereal and milk into the bowls, while scales hidden in the tables measured the amounts of cereal and milk that were served to each child.
The scales and remote sensors also allowed the researchers to determine how much cereal was eaten and how much was left behind after breakfast.
The process was repeated on another day and each child was given the other size bowl.
The children asked for 69 percent more food when they were given the larger bowls. They also ate 42 percent more and wasted 26 percent more when they used the larger bowls.
According to these results, kids are even more influenced by bowl size than adults might be, Wansink said. That may be because they don't have enough experience to know how much food it takes to satisfy their hunger.
"They pour more, they eat more and they also waste more," he told Reuters Health.
Wansink also noted another finding that his group will describe in a forthcoming paper: the effect of bowl size is stronger in kids with outgoing, extroverted personalities. In that analysis, extroverted children were found to serve themselves 33.6 percent more food into larger bowls compared to 5.6 percent served by the typically quieter, introverted children when they were given large bowls.
"Even with a normal sized bowl extroverts are just much more likely to pour a lot more food - not just cereal, we've found it with other things. Probably just because they're excitable people," Wansink said.
"If you have really extroverted kids, you're better off serving them yourself," Wansink said.
Wansink thinks it's a good idea for parents to use smaller bowls for all kids. That way kids will be happy because they're getting a full bowl and parents won't have to deal with excess consumption or wasted food.
"Don't give them the same size bowl that you eat out of, give them something that's more their size," he said.
