This book is written for ordinary people, either suffering from diseases of the gastrointestinal tract, or wishing to avoid them in the future, or seeking to help loved ones. The first part of the book is devoted to the upper part of the digestive system, because the beginning is the most important thing. We will deal with problems of the esophagus, stomach, pancreas, liver, gallbladder, the malfunction of which causes pain, heaviness or heartburn. The second part of the book is devoted to the intestines, which alone make up more than half of the entire digestive system. We will dispel myths about the intestine, learn to correctly understand its symptoms and signals, figure out how to monitor the intestine, how to reduce its irritation and extinguish the bacterial riot taking place in it.