What is "whey protein isolate"?

There are three main types of whey protein, including whey protein concentrate, whey protein hydrolysate and whey protein isolate, reports Medical News Today. Whey protein isolate is made up of 90 percent or more protein, and it is additionally processed to remove all lactose and fat.

Whey and casein are two proteins that make up milk, and whey protein contains nine essential amino acids. Whey protein is a combination of alpha-lactalbumin, beta-lactoglobulin, bovine serum albumin and immunoglobulins, says Medical News Today. Whey protein supplements in conjunction with exercise help build lean tissue mass. Possible side effects include cramps, nausea, headache and reduced appetite.