Cheesy slices of mouthwatering pizza might make a super-easy, cheap weeknight meal for busy families. But American kids are eating way too much of the fatty, salty and unhealthy food, warns a new study published in the journal Pediatrics and reported by NBC’s Today.

For the study, researchers at George Washington University reviewed eight years of kids’ dietary data from the National Health and Nutrition Examination Survey (NHANES). Findings showed that on any given day, 20 percent of children and teens scarf down pizza. On those pizza-eating days, kids typically consume 600 calories over their recommended daily limit. What’s more, the popular food is currently the second-highest calorie source overall for American kids ages 2 to 18, following desserts such as cookies and cake.

This shocking new data prompted nutritionists to tell parents they should cut back on the amount of pizza they feed their kids. “It’s important for people to be aware of what they’re consuming, particularly since obesity is as prevalent as it is and because obesity has so many adverse consequences,” warned William Dietz, MD, director of the Redstone Global Center for Prevention and Wellness at the university and a co-author of the study.

Researchers suggested that families should eat pizza no more than once each week, with kids served no more than two slices. Nutritionists also offered some tips to make pizza night healthier: They suggested eating salad or fruit before phoning in an order, and topping the pie with vegetables, rather than the standard pepperoni slices.