Whey is a product of milk. It can be used for a lot of purposes but it is a common source of protein. Whey protein goes through a filtration process to create the different versions of whey protein: Whey Concentrate, Whey Isolate, and Whey Hydrolysate. Whey Concentrate is the least filtered from other nutrients. Meaning you’ll get a higher fat and carb content with this type of whey protein. Other forms of whey protein, isolate and hydrolysate, are filtered at higher percentage leading to higher protein-to-other nutrient ratio. In these forms of whey protein, it is common to see low fat and low carb labels with the addition of digestive enzymes.