Their is a certain intake in calories your suppose to have what if I eat junkfood and nothing else ?

I don't ever consider calories, and I don't know why the majority of people do?????? Counting calories is so vague because calories come from most everything we put in our mouth, but just as you pointed out, not everything we CAN be put in our mouth OUGHT to be put there. Don't you think it's more clear and specific to count protein, fat, vitamins, cholesterol, and such? That way, if you want to lose weight, you count grams of fat, sugar, and cholesterol. If you want to build muscles, then increase amount of protein. If you need to gain weight, then increase all categories. But just as you pointed out, how do you know what to do by just counting calories??????? If you want to lose weight, so you don't want to consume more than x amount of calories. You can eat nothing but chips and candy bars as long as you don't go over the calorie limit, or eat a hearty meals with meat, vegetables, carbs, and fruit and follow the exact calorie limit. So what is the point of counting calories???????????