It may be surprising to know we are never truly alone. Many, many, tiny, microscopic creatures (microorganisms) live in, and on, our bodies. Those microorganisms are also in charge of many of the body’s tasks that can affect our health.

When you hear the word bacteria, what do you think? Chances are, you think of illness or disease. We’ve been taught to bacteria are bad for us, but not all bacteria are harmful. While it’s true that there are disease-causing bacteria called “pathogenic bacteria,” most bacteria will not harm us! Bacteria exist in just about everything around us – the keyboard, the phone, and even tiny particles in the air. Did you know every drop of water contains more than a million bacteria inside it?

Besides bacteria, there are also viruses, fungi, archaea, amoebae, protozoa, and more. Only about 1,400 species of microorganisms cause diseases in humans and that equals less than 1% of all of the species on Earth. In other words, 99% of microorganisms do not harm us! In fact, many bacteria live in our bodies in perfect harmony with us: we provide them with food and life, and they provide us with nutrients and much more. This collection of microorganisms is what is known as our microbiome.