Generally, when people think about whey protein, they immediately think of its muscle-building benefits. And that's just about it. The truth, however, is that whey protein contains many other highly beneficial substances – allowing it to do so much more for your body than just support muscle growth. A prime example of the potential power of these oft-forgotten chemicals can be seen if we examine some of the research surround the effects of whey protein on cancer. Cysteine and Glutathione Although we usually talk about “protein” as if there is only one type, the truth is that there are many different kinds of proteins – differentiated by their amino acid content. In the case of those proteins provided by whey, all of the amino acids that your body could possibly want are present and accounted for. Of particular significance to our discussion, however, is the amino acid cysteine. Like many amino acids, cysteine can play a variety of roles in your body but is very often converted into a compound called glutathione. An incredibly powerful antioxidant, glutathione has been explored for its potential to treat and prevent a number of serious conditions. Included on the list of targeted illness is, of course, cancer. And in this area, the cysteine found in whey has shown considerable promise. Interestingly, one study found that cancerous tumors actually produce their own supply of glutathione and use it to protect themselves against chemotherapy. You would expect, then, that providing them with more glutathione would be a bad thing. According to one study, however, cysteine supplementation with whey protein actually lowered levels of glutathione in some tumors, making them more susceptible to chemotherapy. Lactoferrin Whey also contains a substance called lactoferrin that has shown potential as an anti-cancer agent – although researchers have yet to decide on exactly how it gets the job done. The prevailing theory is that lactoferrin's power rests in its ability to bond with iron, since its cancer fighting power is increased at this point. Still, however, questions remain as to why that should matter. Regardless of how it happens, lactoferrin has been shown to induce cell death in numerous types of cancer. Ultimately... So, while more investigation is needed, several peptides in whey have already shown some potential in the fight against cancer. It's worth nothing, however, that they substances are often most effective when used to complement chemotherapy and other medical interventions. Read More: Is Organic Whey Protein Healthier? The Bioavailability of Whey Protein Isolate Why Unflavored Protein Powder Should Be a Staple in Your Pantry