The strategy they propose is simple. When kids were presented with food choices, researchers from Cornell University found that invoking the names of superhero role models helped sway them away from junk food towards healthier foods.

In their small sample study, researchers presented 22 children ages 6 to 12 with photos of real and fictional superheroes and role models before asking, "Would this person order apple fries or French fries?"

"Apple fries" -- or raw apple slices -- are available at some fast-food restaurants like McDonald's and Burger King as an alternative to deep-fried potatoes.

When the children were given no prompts, only 9 percent (or 2 kids) chose the apple fries. Following the superhero cues, however, that figure rose to 45 percent or 10 children who passed over the potato fries.

The study, published in the journal Pediatric Obesity, comes as Christopher Nolan's film The Dark Knight Rises rakes in millions at the box office and just weeks after the release of The Amazing Spider-Man.

'Shave three pounds of weight a year'

Swapping fries for apples can add up to a lot less when it comes to calorie intake. On average, kids who selected apple fries consumed 34 calories per meal, compared to 227 calories when they opted for French fries.

"If you eat fast food once a week, a small switch from French fries to apple fries could save your children almost 3 lbs (1.4 kg) of weight a year," said lead researcher Brian Wansink in a statement.

"Fast food patronage is a frequent reality for many children and their parents. Simply instructing a parent to order healthier food for a child is neither empowering for a child nor easy for a parent," Wansink added. "Advising a parent to ask their child 'What would Batman eat?' might be a realistic step to take in what could be a healthier fast-food world."

Another study published in the American Journal of Clinical Nutrition this spring found one of the best ways to get kids to get their vegetables was for parents to do the same, leading by example. Similarly, stocking the kitchen with healthy snacks, maintaining regular meal times and taking kids to the grocery store so they become engaged with their food are also recommended strategies.