Why do some products pretend that the whey protein is 100 percent pure when the concentrate has only 80 percent of protein. I wonder what is in the other 20 percent?

It is true that many Whey Protein producers and sellers will advertise the product in this way. The answer is not that complicated. 80% refers to the level of protein that can be found in the whey concentrate. If you see a product that says that it is 100% whey, it refers to the source of the protein. This means that it is made 100% from whey, not from milk, soy, eggs etc.

The truth is that the products that say to be 100% whey protein will have an amount of 80% pure protein. The remaining 20% will be made up of moisture, fat, carbohydrates, vitamins and minerals. All powders also contain some amount of moisture, so approximately 5% will be from water. Vitamins and minerals account for a further 5% or so. The remaining part is represented by the fat and carbs that are still there though these tend to be low. Depending whether you choose flavoured or unflavoured product as small amount of flavour, colour and sweetener will also be added. There is no need to be concerned that the product is not what it says it is.