Digestive system diseases include some common disorders, like lactose intolerance, and some more uncommon diseases of the digestive system. What are digestive disorders? This list of digestive system disorders and dietary disorders includes some of the more disruptive stomach diseases. What are digestive diseases? Digestive tract diseases can be life threatening if left untreated. Feel free to use this list to make your own checklist of stomach and intestine system diseases.What diseases/disorders effect the digestive system? Every part of your body is important but one of the most important parts is your brain. Finding out what brain disorders commonly affect people is a good way of protecting yourself because knowledge is power. Your circulatory system is also very important so see this circulatory system diseases list and keep yourself informed. If you are up for a good laugh check out peyronie's disease but be warned that you may encounter graphic content.