This is an explanation of the ways in which friendly bacteria can contribute to a healthy human body. Probiotics improve nutrition and protect against disease, and this book outlines their nature and their role in the management of the body. The inclusion of friendly bacteria in the diet is beneficial to the balance of the intestinal, urinary and vaginal tracts. It also has antibiotic, antiviral and antifungal powers against a variety of infections. The book includes chapters on the potential of probiotics for fighting cholesterol, tumours, liver disease, cancer and stress, and for contributing to infant health. The various species and strains of bacteria are identified, and those with desirable properties are recommended for dietary supplementation. The benefits of freeze-drying and concentrating these species are explored. The aim is to promote good health for everyone, though the study will be of special interest to the nutritionist and medical workers.