A method of treatment of cancer with a formulation of liposomally encapsulated glutathione, that is preferably used orally, increases the level of glutathione in tissues in order to prevent and reverse the metabolic changes in cells that results in the formation of the metabolic “fuel supply” that supports cancer cells, and without which the cells can die out. The method prevents the oxidative stress that damages normal support cells such as stromal fibroblast cells. By blocking the “fuel supply,” the invention can protect, prevent and reverse these cells from the steps of autophagy and mitophagy, that results in the cells decreasing the normal production of ATP for energy and using aerobic glycolysis for energy production. The use of oral liposomally encapsulated glutathione will maintain the presence and normal function of caveolin in fibroblast and other cells, thus preventing their conversion to autophagic tumor stromal cells.