Glutathione (or GSH) is called the Master Antioxidant because it plays a crucial role in the body's antioxidant defense system. It is involved in protecting cells and tissues from oxidative stress and inflammation, and it helps to repair and restore damaged cells. GSH is a powerful antioxidant that can directly quench free radicals and neutralize a wide range of harmful substances, including toxins, heavy metals, and harmful chemicals. It is also involved in the synthesis and maintenance of other important antioxidants, such as vitamin C and E, and it helps to support the body's immune system by boosting the production of white blood cells. Overall, GSH plays a vital role in maintaining the body's overall health and well-being, and it is considered the Master Antioxidant because of its multifaceted and essential roles in the body.