What is protein? What does it do for our bodies and how much should we eat each day? Protein is the building block for all of our cells, and without it, muscle development isn't possible. Think of protein as the oil in the car, you need to have it on board for the car, or your body, to operate properly. Fat and carbohydrates are like the gas, the amount needed varies on your activity level. Check out the following video from Jeremy Mullins...he does a great job explaining why protein is so important.