How bad is it to snack/graze on cereal all work day?

SO MUCH SUGAR!!!

It ain't good. I'll say that much. I mean those calories you are taking in are completely wasted garbage calories. Processed carbs, sugars, etc. and minimal nutritional benefit. Try snacking on veges and fruits. Grazing is a good thing, I think, if you are grazing on the right food.

A healthy cereal isn't bad...HOWEVER, it will mess with your metabolism. Your body will get used to being constantly fed which leads to 2 things: 1) You may start losing your sense of when you are really full because grazing can lead to mindless eating. This means not realizing when you are full even while eating a real meal. 2) What about on the weekends or when you run out the multi-grain cheerios? Most people who are used to grazing will continue to "graze" and find something to eat all day...when you're out of the multi-grain cheerios, you might grab whatever is available because you are "starving" because your stomach is used to constantly having that food in it.

I would recommend eating smaller meals more frequently. Breakfast at say 7 am, lunch at maybe 11 am, snack at 3 pm, dinner at 6 pm?

Calories ARE calories, but that doesn't mean that the food containing them is equal. Eating 500 calories of butter does not yield the same effect as eating 500 calories salad or whole grains.

Eating constantly is also not a bad thing. Eating throughout the day, staving off hunger and bad impulses, building healthy food connections, reinforcing a routine of positive emotion with healthy food sounds like a good function of continual grazing. When I am at my healthiest, all I do is graze, really. There is never a defined mealtime or serving size because 'meals' become each individual food item that I put in my mouth.

This morning for breakfast I had a yogurt. A bit later I had some banana. In a little while I will have a protein bar and maybe some soymilk.