An Emerald Guide. The Digestive system plays a major role in our overall health, as it is the channel for nutrients our bodies require for survival. Without good digestive health, you will experience a host of uncomfortable conditions and life threatening illnesses. This is why digestive health is so important. This book is a perfect balance of science and practical advice. It explains how your digestive system works and what happens when it doesnt function properly. It also provides everything you need to take control of your general health, through close and careful attention to your digestive system.