I Contain Multitudes: The Microbes Within Us and a Grander View of Life

by Ed Yong

Even now, the photosynthetic bacteria in the oceans produce the oxygen in half the breaths you take, and they lock away an equal amount of carbon dioxide.

there are more bacteria in your gut than there are stars in our galaxy.3

There are fewer than 100 species of bacteria that cause infectious diseases in humans;8 by contrast, the thousands of species in our guts are mostly harmless.

Many conditions, including obesity, asthma, colon cancer, diabetes, and autism, are accompanied by changes in the microbiome, suggesting that these microbes are at the very least a sign of illness, and at most a cause of

Every person aerosolises around 37 million bacteria per hour. This means that our microbiome isn’t confined to our bodies. It perpetually reaches out into our environment.