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Most of us grow up thinking that bacteria is terrible. It’s lurking on our toys, on doorknobs, and even in the air. Yet, the thinking that all bacteria is harmful is actually a flaw. We are always surrounded by bacteria, and there are even bacteria living inside of us right now. It helps to think of bacteria as either harmful or helpful, and here are some tips for figuring that out.

Beneficial Bacteria

When humans and bacteria have a mutualistic relationship, both parties benefit. An excellent example of this is the bacteria that live on and in our bodies. We serve as a host to the bacteria, and the bacteria are gracious guests, keeping harmful microbes out of our bodies and feeding. Think about gut bacteria, which lives inside our gut microbiome and helps us digest food and make the most of the nutrients in our food.

Negative Relationships

On the other hand, some bacteria create a parasitic relationship between them and us. While the bacteria benefit from the relationship, we experience adverse effects such as illness. Some common examples of these types of bacteria include pneumonia, tuberculosis, and salmonella. These bacteria produce endotoxins and exotoxins, which are substances that harm our well-being and cause diseases to develop.

Good or Bad?

There are still other types of bacteria that benefit off of us without harming or helping our bodies. It might seem strange or gross to be hosting bacteria that do nothing for us, but it’s a fact of life. A well-researched example of this is a bacterium that lives on our skin. There are some cases in which this kind of commensal bacteria becomes harmful and other instances in which it becomes helpful for us.

The final answer on whether bacteria are good or bad is that it’s both, but more often than not, bacteria are good for our overall health.