May 11, 2010
Dear Dr. Cordain,
Could you please provide some details on the benefits/detriments of whey protein supplementation? I am a weight trainer/powerlifter and supplement with whey protein, which is currently touted as the best/most health-conscious choice there is. I have read in your newsletter about the inflammatory aspects of dairy products – is whey protein included in this? Is it better or worse than other dairy products?
Many people interested in the Paleo Diet who are also into strength training and fitness would be interested in your thoughts on this. Any pointers re: inflammation and supplementation of protein would be very well received. Thank you, in advance.
Dr. Cordain’s Response:
Unfortunately, at this point, most of the research has focused on the beneficial effects of whey. It basically revolves around whey’s high BCAA content, its use as a post-workout recovery drink ingredient, and its capacity – due to cysteine – to increase Glutathione, a powerful endogenous antioxidant enzyme.
Nevertheless, we believe that whey protein can have some potential adverse effects, because it greatly elevates insulinemia – although it can be therapeutic for diabetics in the short term. We 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.).
But to be completely sure, we would need intervention studies with whey protein with a relatively long duration in people genetically prone to insulin resistance, or who are in fact insulin resistant.
Also, there is the matter of hormones in milk: estrogens, DHT precursors, Insulin, IGF-1 and the hormone Betacellulin (BTC), which Dr. Cordain has discussed in a previous edition of this newsletter. These are some of the possible mechanisms for which there is repeated epidemiological evidence associating milk consumption with some cancers – especially Prostate Cancer.
We know that these hormones are present in milk and – in the case of BTC – it is present in whey too. Nevertheless, the real content of all these hormones in commercial milk-derived products is an open question that deserves proper and urgent study. So while we don’t know for sure, and since and we have alternatives, I would follow the old saying: do no harm!