It was theorized that protein loss during fasting was harmful and that a fast should be supplemented with protein. Fasting with protein became known as the Opti-fast. Fasters took nothing but water and a protein drink. Sadly, several people died. Protein digestion during the fasting state created an overload of urea and the blood become acidic. In this condition, the organs become more damaged instead of healing. To the body, fasting is a natural process. During water or juice fasting, the protein levels of the blood remain constant. Although protein is being utilized, a person fasting 40 days on water will not suffer a deficiency of either protein, vitamins, minerals or fatty acids. In the breakdown of dying and diseased cells, all essential substances are available while fasting for reuse within the body. These dead cells are utilized in a systematic manner.