Our ancestors ate whole animals. Skin, cartilage, tendons, bones, organs. That meant they consumed massive amounts of glycine from collagen rich tissues. Modern humans eat almost exclusively muscle meat, which is extremely high Glutathione for Type 2 Diabetes: How It Restores Immunity C peptide is a biomarker for beta cell function. In other words, it's a measure of beta cell health and insulin production, and is critical to developing new disease modifying therapies for type 1 Glutathione metabolism in type 2 diabetes and its relationship with microvascular complications and glycemia PLOS One Evaluation of Glutathione S Transferase GSTM1 and GSTT1 Deletion Polymorphisms on Type 2 Diabetes Mellitus Risk PLOS One