When you think of the microbiome, you probably think of your gut. But bacteria live all over your body. And they’re incredibly numerous; you play host to about as many microbes — a hundred trillion of them — as you do human cells.

As my guest will explain, these microbial ecosystems are not only ubiquitous but hugely influential for your health — impacting everything from your weight and mood to your risk of developing many diseases.

Dr. Brett Finlay is a microbiologist and the co-author of The Microbiome Master Key. Today on the show, Brett explains what the microbiome is, how modern life — including our overemphasis on hygiene — has damaged it, and how the quality of your microbiome is connected to nine of the top ten leading causes of death, as well as everything from depression to Parkinson’s. Brett also shares how we can boost the health of our microbiome, including whether probiotic supplements are effective, how something as simple as flossing your teeth can cut your risk of Alzheimer’s by 50%, and why you might want to let your dog lick you in the face.

• Let Them Eat Dirt documentary
• AoM Article: How and Why to Eat More Fiber
• AoM Article Don’t Be a Stick in the Mud — Why You Should Let Your Kids Get Dirty
• Probiotic gum

• Brett’s faculty page