If the thought of bacteria conjures images of germs that should be avoided at all costs—and certainly not ingested—think again! Some friendly bacteria, called probiotics, are not only beneficial to your health, they’re essential. Now an internationally recognized scientist at a top U.S. medical school—one of the leading researchers in the field—sheds light on the extraordinary benefits of these natural health superstars.

Thanks to an explosion of research in recent years, one thing is clear: probiotics, the healthy bacteria that inhabit the digestive tract, are the body’s silent partners for good health, optimizing the power of the immune system to fight disease and the “bad” germs we fear. But how do they work? And in the face of factors like stress and poor diet, which decrease their numbers, how do you keep your supply well stocked?

Here is an up-to-the-minute, highly accessible guide to probiotics and the foods and supplements that contain and support them—many of which may be in your diet already. Discover:

The key role of probiotics and prebiotics in restoring healthy balance to our bodies, improving immune system functioning, and curbing inflammation

How to use probiotic foods and supplements to prevent and relieve allergies, inflammatory bowel disease, irritable bowel syndrome, yeast infections, and the negative side effects of antibiotic use

New evidence that probiotics may help fight asthma, cardiovascular disease, breast and colon cancer, autoimmune diseases, chronic fatigue, fibromyalgia—and even obesity

Natural sources of prebiotics, the nutrients that help make the digestive tract more hospitable for probiotic bacteria

The Probiotics Revolution also includes a step-by-step plan for incorporating the many food sources of probiotics and prebiotics into your diet, a complete buyer’s guide to probiotic supplements, and how to introduce probiotics to your family and children.

“Our culture has gone way too far in its war on germs. The end result is bacterial imbalances that are implicated in everything from allergies and asthma to chronic fatigue and heart disease. The Probiotics Revolution is must reading for everyone who is interested in achieving or maintaining vibrant health.”—Christiane Northrup, M.D., author of Women’s Bodies, Women’s Wisdom and The Wisdom of Menopause

“Probiotics represent the next wave of health and healing. Whether you are concerned about your immune system, digestion, hormones, allergies, or skin, The Probiotics Revolution provides cutting-edge research with down home and practical solutions.”—Ann Louise Gittleman, Ph.D., C.N.S., author of The Fat Flush Plan

Gary B. Huffnagle, Ph.D., is Professor of Internal Medicine, Microbiology, and Immunology, University of Michigan Medical Center. His research on probiotics has appeared in leading scientific journals and has been featured in Newsweek, Forbes, and on BBC News.

Sarah Wernick is the coauthor of several bestselling health books, including Strong Women Stay Young.