Does cereal help or hurt with weight loss?

Depends: On what else you eat with it. It can fill you up in the morning, but the fullness might not last as long as having some protein with the cereal. For most of us a calorie is a calorie.

HURT: Cereal is high in carbs and usually comes with a load of sugar (otherwise it tastes like wood shavings). In very basic terms this is how we get fat: carbs drive insulin, Insulin drives fat gain.