Whey protein isolates are 90 pure protein by weight they are the purest and most expensive form of whey protein that exists thats why they are the first ingredients you read on the 100 whey gold standard label by using whey protein isolates as the primary protein source optimum nutrition have been able to pack 24 grams of the purest muscle building protein per serving with a lot less of the fat cholesterol lactose and other stuff that you can do without theres no question this is t