7 Powerful Natural Sources of Glutathione for Optimal Health Glutathione is such an important antioxidant in human physiology, meaning it acts to combat oxidative stress. Strategies for increasing glutathione include: Consume sulfur rich foods like cruciferous vegetables Ensure you get Foods With L Glutathione: Avocado, Watermelon, and More GoodRx 15 Effective Foods to Boost Glutathione Levels Naturally