Protein powder, a dietary supplement made with whey, spirulina, eggs, soy or rice as its primary source of protein, can go bad. However, storing it in a dry area away from high heat helps increase its shelf life.
Since protein powder is a powder, it is easy to store in a well-sealed container. Powder absorbs any moisture it's near, so when using the container, keep its contents from getting wet or damp. Check the container's expiration date. If there are any doubts about its quality, look inside and give it a sniff. If it hasn't developed new colors or rancid smells, it is most likely still good. However, older protein powder has less nutritional value