Your body produces glutathione naturally in all of your cells, however, it is most prominently produced in the liver. (theivdoc.com)
You will also want to eat foods that help to produce glutathione in the body as mentioned above. (colonzone.org)
We also know some veggies, like sulfur - rich veggies (cauliflower, cabbage, etc.), are good for producing glutathione, a powerful antioxidant that's good for the mitochondria. (mindbodygreen.com)