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Macmillan Childrens Publishing Group
Dirt Is Good

Dirt Is Good

The Advantage of Germs for Your Child's Developing Immune System

Jack Gilbert, Ph.D., and Rob Knight, Ph.D., with Sandra Blakeslee

St. Martin's Griffin


From two of the world’s top scientists and one of the world’s top science writers (all parents), Dirt Is Good is a q&a-based guide to everything you need to know about kids & germs.

“Is it OK for my child to eat dirt?”

That’s just one of the many questions authors Jack Gilbert and Rob Knight are bombarded with every week from parents all over the world. They've heard everything from “My two-year-old gets constant ear infections. Should I give her antibiotics? Or probiotics?” to “I heard that my son’s asthma was caused by a lack of microbial exposure. Is this true, and if so what can I do about it now?”

Google these questions, and you’ll be overwhelmed with answers. The internet is rife with speculation and misinformation about the risks and benefits of what most parents think of as simply germs, but which scientists now call the microbiome: the combined activity of all the tiny organisms inside our bodies and the surrounding environment that have an enormous impact on our health and well-being. Who better to turn to for answers than Drs. Gilbert and Knight, two of the top scientists leading the investigation into the microbiome—an investigation that is producing fascinating discoveries and bringing answers to parents who want to do the best for their young children. Dirt Is Good is a comprehensive, authoritative, accessible guide you've been searching for.


The Microbiome

Earth formed about 4.5 billion years ago when a disc-shaped cloud of dust and gas collapsed into a primordial sphere. It was lifeless and molten and reeked of lethal gases. When it finally cooled, a newly solid...

Praise for Dirt Is Good

“A deeply informed, fascinating and fun guide for parents, healthcare professionals and anyone else interested in the latest microbiome research, from two of the nation’s leading researchers.” —Ted Anton,Professor of English at DePaul University and author of Planet of Microbes: The Perils and Potential of Earth’s Essential Life Forms. -

Reviews from Goodreads

Jack Gilbert, Ph.D., and Rob Knight, Ph.D., with Sandra Blakeslee

JACK GILBERT, PhD is a Professor of Surgery at the University of Chicago and Director of the Microbiome Institute.

ROB KNIGHT, PhD is Professor of Pediatrics and Computer Science & Engineering and Director of the Center for Microbiome Innovation at the University of California, San Diego. He is co-founder of the Earth Microbiome Project and American Gut. Rob is the coauthor of Follow Your Gut and Dirt is Good.

SANDRA BLAKESLEE has worked for the New York Times for nearly 45 years, winning multiple journalism awards.

image of Jack Gilberto
Nancy Wong for the University of Chicago Medicine

Jack Gilbert

image of Rob Knighto
David Ahntholz

Rob Knight

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