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 10 Foods That Contain Glutathione Core Med Science Which foods are highest in glutathione ? Want to naturally boost your glutathione levels? These foods are your secret weapons. Incorporate these into your diet and experience the glow from within! Share this with your friends