It may surprise you to know that there is a system in your body so complex that it contains almost 500 million neurons, linked to your brain. Would you ever guess that it is your gastrointestinal (GI) system, otherwise known as your gut? To help shed some light on the importance of gut health for the whole body, we talked to Jagrati Mathur, MD, a gastroenterologist with Dignity Health Medical Group — Saint Francis/St. Mary’s.