Your body is home to trillions of tiny bacteria. If you gathered them all up and put them on a scale, they would weigh as much as a large brick or a bag of rice!
It might sound a bit creepy, but right now, there are trillions of tiny living things crawling all over and inside you. These are bacteria, and they are so numerous that they make up a significant part of your body weight.
Individually, a bacterium is so small you can't see it without a microscope. But because there are so many of them (roughly 38 trillion!), their weight adds up. For an average adult, all these microbes weigh between 1 to 2 kilograms (about 2 to 4.4 pounds). That is roughly the same weight as your brain!
Most of this "microbial weight" is tucked away in your large intestine (your gut). This is where your body's "engine room" for digestion is located. While you also have bacteria on your skin, in your mouth, and in your nose, the vast majority live in your digestive system, helping you break down food and keeping your immune system strong.
Don't worry - you don't need to go take a bath in bleach! Most of these 2kg of bacteria are "good guys." They protect you from harmful germs, produce vitamins that your body can't make on its own, and even help influence your mood. Without this 2kg of tiny helpers, you wouldn't be able to stay healthy.
Your body is an ecosystem. About 2kg of your total weight comes from the bacteria living inside you. They are essential partners that help you digest food and stay safe from diseases.
