Hi! And thanks for asking such an important question- where SO many people are confused. Knowing the calories per portion is a two step process. (1) Read the calories per serving; (2) Look for the servings per container. That is where the confusion can come in, in step 2. So, for 120 calories in a 1 cup bowl of cereal, you need to measure out 1 cup from the whole box, to make sure you get the 120 calories. Sometimes, the serving size IS the whole container. Like for a package of nuts, it might say 180 calories per serving. If the servings per container says "one", then the whole bag is your serving. Sometimes the label says "servings per container=4", which means you need to take the whole box and divide it into 4 servings to get the accurate calories. Many products help you with that - and give you the specific amount - like 1/2 cup, or 3/4 cup, and others just tell you there are 4 (or whatever) servings in the box, and you have to figure it out.
Be a careful label reader, and you will be able to accurately monitor your calories per serving.
I hope this clarifies your thinking on this! Good luck, and let me know how you are doing!
