It is a time-honored parenting technique to tell children inflated truths — otherwise known as lies — whenever we are trying to teach them something we believe they ought to know. Persuading children to eat healthy meals, for example, we tell them all the good things a particular food item will do for them. Carrots will help you to read, we say in a bright voice, because they’re good for your eyes! You’ll do better on your math quiz tomorrow if you eat a salmon burger! In fact, this approach is all wrong, according to a new study from a team of marketing professors. When children hear about the benefits of healthy food, they’re less likely to eat it.

Although Popeye is no longer a featured player in children’s cartoons, many former children still have fond memories of the spinach-eating sailor man. It is said E. Segar, the creator of Popeye, had been influenced to promote spinach due to a misplaced decimal point in the calculations of the amount of iron in the leafy vegetable. In any event, Popeye has been credited more than once with increasing American spinach consumption by 33 percent during the 1930s.

Despite Popeye’s (debatable) social impact, the authors of the current study had their own ideas about children and healthy eating. “We predicted that when food is presented to children as making them strong or as a tool to achieve a goal such as learning how to read or count, they would conclude the food is not as tasty and therefore consume less of it,” write Dr. Michal Maimaran of Northwestern University and Dr. Ayelet Fishbach of University of Chicago. To test this hypothesis, they conducted five experiments with pre-schoolers between the ages of three and five.

In all five studies, the researchers read the children a picture book story about a girl who ate a snack of crackers or carrots. In some cases the story stated the benefits of the snack — making the girl strong or helping her learn how to count. In other cases, the story did not mention the benefits of the snack. Next, the researchers offered the children a chance to eat the food featured in the story.

Naturally, the results of these experiments fulfilled the authors' expectations. The children ate more when they did not receive any positive messages about the food's benefit. “Parents and caregivers who are struggling to get children to eat healthier may be better off simply serving the food without saying anything about it," the authors conclude. "or (if credible) emphasizing how yummy the food actually is." Mentioning Popeye might also work.

Source: Maimaran M, Fishbach A. If It’s Useful and You Know It, Do You  Eat? Preschoolers Refrain from Instrumental Food. Journal of Consumer Research. 2014.