At least a significant percent of the population, if not the majority, is said to be lactose intolerant: http://en.wikipedia.org/wiki/Milk#Lactose_intolerance

At least a significant percent of the population, if not the majority, is said to be lactose intolerant: http://en.wikipedia.org/wiki/Milk#Lactose_intolerance http://en.wikipedia.org/wiki/Milk#Lactose_intolerance Besides that, if you ingest a protein shake and eat nothing for a few hours the toxic waste products of digesting the protein will stay in your bowels longer then with a richer meal.