Editing serving size

It is not that food don't "fit" the standard serving size. It is more that the people that determine serving size are not always realistic. Most food nutrition information is created by the producer and advertisers. In order to be able to call something "low calorie, low carb, low fat, low sodium, low sugar and the like, they reduce the size of what you can eat of a product so that its not false information. However, in most cases, it is usually a portion sized for a 3 year old, not for a person who is at a healthy, adult weight. If they put labeling accurate for what an active adult would eat, then none of their products would be able to advertise as being healthy. Dietitians and Nutritionists are workers too, and will do what is necessary to earn their pay, and in some cases it may be required for them to put "inaccurate" standards in order to keep getting a paycheck. It happens. Just take that information as suggestions and recommendations and as others keep saying, weigh your foods. A scale doesn't lie, whether we like it or not. If you want to to the mathematical breakdown of calories (or other nutrients) per gram, you can then create an accurate serving based on your own desires.