Children consume more low-nutrition, high-calorie food such as cookies and candy after observing seemingly overweight cartoon characters, according to a first-of-its-kind study led by the University of Colorado Boulder.

The results of the new study, involving Colorado State University and published online in the Journal of Consumer Psychology, show that kids are responsive to the apparent bodyweight of cartoon characters like the aptly named Grimace, a rotund, milkshake-loving creature created by McDonald’s restaurant in the 1970s.

Children tend to perceive ovoid, or egg-shaped, characters as overweight even though the creatures are imaginary, found the study.