What’s Up With the Bacteria in Your Gut?

What’s Up With the Bacteria in Your Gut?

The overuse of antibiotics, eating processed foods, and a generally sanitized lifestyle in industrialized nations is contributing to people's ill health and many modern plagues.


3 - 12+


Biology, Health, Social Studies


Beneficial Gut Bacteria

Gut bacteria, which form our microbiome, play an essential role in our emotional health as well as our physical health. Fiber-rich prebiotic foods, like fruits, vegetables, and whole grains as well as probiotic fermented foods are recommended for our micr

Darryl Leja
Gut bacteria, which form our microbiome, play an essential role in our emotional health as well as our physical health. Fiber-rich prebiotic foods, like fruits, vegetables, and whole grains as well as probiotic fermented foods are recommended for our micr
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We have a lot of bacteria living in our guts, or intestines. Your body needs gut bacteria to help it break down food. These bacteria are part of the gut microbiome. A microbiome is the collection of microbes in a particular place. Your gut's microbiome has hundreds of types of bacteria. The gut microbiome plays a role in nutrition. It can affect our health in many other ways, too.

Poop Is Everywhere, But That's A Good Thing

Throughout our lives, we collect bacteria. You start when you are born. You collect bacteria when you pass through your mother's birth canal. Your mother's milk has bacteria, too. These bacteria help break down some of the substances in milk. Milk also gives our microbes something to eat.

By the time kids turn three, their microbiomes are fully formed. This means that they have come in contact with a large number of fecal particles. These are particles of poop. According to scientists, the environment is pretty much coated in fecal particles. It sounds gross, but it is a good thing. We collect bacteria. They provide us with vitamins. They help us fight infections. They make chemicals that help us stay happy and healthy.

Junk Food Can Kill Off Good Bacteria

Our bacteria protect us from illnesses. But recently, scientists say that illnesses have increased in the population. Diseases like diabetes have increased. So have allergies and asthma. Scientists think this means something is wrong with the bacteria in our guts.

The problem might be a leaky digestive tube. It separates the gut and the rest of the body. Bacteria keep this tube healthy. Without the right bacteria, it breaks down. Toxic bacteria enter the blood. This sends a signal to the immune system. The immune system protects the body. It thinks there are invaders, so it attacks. This causes health problems that last for a long time.

Scientists say that our microbiomes are not what they used to be. It's because people eat too much junk food. They also are using too many antibiotics. These are medicines that fight bacterial infections. But they can wipe out good bacteria, too. A combination of these factors might be the reason for many modern diseases.

Exercising, Eating Fiber-Rich Foods Can Help

How can you keep your microbiome healthy? Scientists and doctors say that we should eat healthy foods. Fermented foods are foods in which the molecules are broken down by yeast or bacteria. Examples include yogurt and miso soup. These are good for us. Fiber-rich foods also keep us healthy. Examples are whole grains, fruits and vegetables. Exercise helps your microbiome too.

The more bacteria you pick up, the better it is for you. So, go outside more. Meet new people, pet the dog, dig in the garden, and play in the dirt.

Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.

Tyson Brown, National Geographic Society
Rebecca Rupp
Production Managers
Gina Borgia, National Geographic Society
Jeanna Sullivan, National Geographic Society
Program Specialists
Sarah Appleton, National Geographic Society, National Geographic Society
Margot Willis, National Geographic Society
André Gabrielli, National Geographic Society
Last Updated

July 19, 2022

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