Researchers found that even though 5-year-olds in their study generally didn't finish small-size portions of various entrees, they typically ate more when they were given a super-sized serving of the same food.
The findings, published in the American Journal of Clinical Nutrition, add to evidence that large portion sizes encourage overeating.Experts have pointed to the food industry's often generous portion sizes as one of the factors fuelling the obesity problem. And some studies in the nutrition lab have shown that adults and children tend to eat more when their meal is served in large portions.
The study, led by Dr Jennifer O. Fisher of the Baylor College of Medicine in Houston, included 59 low-income African-American and Hispanic children, groups at particular risk of obesity. The children and their mothers spent 2 days at the Baylor Children's Nutrition Research Centre, where their daily calorie intake was monitored.
On one day, mothers and children were given meals and snacks in standard portion sizes; on the other day, they ate the same meals, but with the main item of each meal doubled in portion - including macaroni-and-cheese at lunch, and chicken at dinner. Their afternoon snack was also a double portion.
Fisher's team found that when children were served the double-size portions, they ate an average of 180 calories more from those foods for the day. They did eat slightly less of the foods that were not super-sized, but that did not make up for the extra calories
A similar pattern was found among mothers. But the effect was even greater for their children, who ate an average of 12 percent more calories on the "large-portion" day, versus 6 percent for mothers.
It's unlikely that the children ate more on the large-portion day because the smaller portions were simply too small, according to the researchers. They point out that the children typically ate less than two thirds of the smaller portions.
The findings do suggest that large portions contribute to a dietary environment that promotes obesity surrounding many US children, according to Fisher's team.
However, they conclude, long-term studies are needed to see whether portion sizes are in fact directly related to children's risk of becoming obese.
SOURCE: American Journal of Clinical Nutrition, December 2007. – (Reuters Health)
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