What Food Has the Highest Amount of Glutathione? Exploring Nature's Antioxidant Powerhouse Cymbiotika CYMBIOTIKA Foods With L Glutathione: Avocado, Watermelon, and More GoodRx Because glutathione levels decline as you age, and glycine can help slow the glutathione slide, it's a good idea to keep your levels high by eating protein rich foods, like organic poultry, grass fed Foods High in Glutathione Dr. Christina Carlyle Natural Ways to Boost Your Glutathione Levels (Without Expensive Supplements)