Macronutrients:
Your food is made of up many different types of molecules, which fall into three major categories: proteins, fats, and carbohydrates. Everything you eat contains these building blocks in different proportions, and your body processes, digests, and stores these substances in your body differently. Your nutritionist/dietitian teaches you about each of the three macronutrient categories, and how you should think about them practically as you go about preparing and eating your meals.