SpongeBob SquarePants, Shrek and other characters kids love should promote only healthy food, a panel of scientists recommended.

The Institute of Medicine said television advertising strongly influences what children younger than age 12 eat. The report said the food industry should spend its marketing dollars on nutritious food and drinks. Popular animated characters should endorse only good-for-you food, the panel concluded.

The report said evidence is limited on whether TV advertising leads to obesity in children. A study hasn’t been done that would demonstrate a direct cause and effect.