New York, Jan 7 (IANS): A small incentive with a meal consistently motivates kids and adults to choose smaller portions, says a new study.

Researchers found that the brain responds to a small toy, gift card, or lottery ticket in the same way it does to a mouth-watering burger or cheese-slathered pizza.

In a series of experiments, the researchers found that the majority of children and adults chose a half-sized portion meal paired with a toy or monetary prize over a full-sized portion meal without a toy or monetary prize. The price of the two options was kept the same.

The researchers found that people were more likely to choose a smaller meal for the chance to win a $10 lottery than to get a guaranteed reward. The premiums in the study were the chance to win $10, $50 or $100.

"The fact that participants were willing to substitute part of a tangible food item for the mere prospect of a relatively small monetary premium is intriguing," said one of the researchers Martin Reimann, assistant professor of marketing at University of Arizona in the US.

The study also pointed out that individuals could celebrate achievements like a job promotion, with something other than food and still be happy.

The study was published in the Journal of the Association for Consumer Research.