Many of us have wondered about what exactly we are eating. Typically, we can distinguish between what is good or bad nutritionally for us, and what tastes good or bad. And, we recognize that even though flaming hot Cheetos are bad for us, we may eat them anyway because they taste good. But, while we can read the nutrition fact labels on the packages of many foods, informing us of the quantities of calories, carbohydrates, fats, proteins, etc. these don’t explain why these are good or bad for us. There are three main forms of macronutrients: carbohydrates, lipids, and proteins, all of which are incredibly important to our overall health, nutrition, and evolution.