If you know the nutritional values of your food, it's easier to know what you have and don't have daily. It seems daunting at first, I know. But, it becomes second nature after a while. If you're getting enough vitamins, but lacking on minerals like Iron, Zinc and Potassium, you're more likely to meet your nutritional needs long before symptoms of lacking in those minerals appear. Head off nutritional deficiencies before they become real problems!