Most people assume "protein" is a nutrient. This isn't true. Protein is macronutrient category--think of it as a family of nutrients. Most of these nutrients are amino acids--cell building blocks. Each protein source (beef, chicken, whey, soy, etc.) has its own amino acid profile--that is, the composition of each is very different from the composition of the others.
Protein is an essential part of your diet, just as the two other macronutrients (fat and carbohydrate) are essential.
For building muscle we will stick to whey protein as this is supposed to be the best form of protein and is the most easily used by the body.
