Whey protein definitely helps to increase lean muscle mass. Without protein, you may spend hours in the gym and never increase your lean muscle mass simply because you cannot grow a muscle without protein. It has also been discovered that whey protein has many other health benefits. It is useful for weight loss, specifically fat loss.
Brain function relies on appropriate protein.
It enhances immune function by increasing important glutathione levels. There is much more. Whey protein has been researched in prevention and life extension studies for such things as cancer, AIDS and other degenerative diseases. Whey protein is now the most biologically available protein on the market which is why athletes reach for it as their first choice. This means that whey protein is the most easily absorbed, easy to utilize protein, with the most protein per serving.