Whey protein has large amounts of high Branched Chain Amino Acids (BCAA) and is often used as a post-workout recovery drink They contain cysteine – which increases Glutathione, a powerful endogenous antioxidant enzyme.
The concern about whey protein is that it can have some potential adverse effects, because it greatly elevates insulinemia – although it can be therapeutic for diabetics in the short term. I suspect that whey protein could be detrimental long term, as hyperinsulinemia can down-regulate the insulin receptor and lead to insulin resistance. Insulin resistance underlies the Metabolic Syndrome, and is implicated in various other diseases, such as Acne, Alzheimer, various cancers, Coronary Heart Disease, Myopia, PCOS, etc.
We have alternatives if you are allergic to whey or concerned about long term effects. UltraMeal shakes are also made from soy or rice. I would swithch out my protein powder sources every six to eight weeks. Snack on lean meat and seafood because these are very good sources of BCAA. If you want a protein drink immediately after strength training to speed recovery and increase muscle mass, I would suggest ~9 grams of essential amino acids, using Metagenics BioPure Protein along with bluberries or a banana.