When your child thinks of bacteria, she probably thinks of the ugly depictions of germs in TV commercials for cleaning products: slimy, green little monsters that are up to no good. In reality, bacteria is a very important aspect of health, and "good" bacteria help the body to function properly. Kids generally enjoy a story featuring "good guys" and "bad guys," so the tale of good and bad bacteria is likely to be a compelling one for your child.
Tell your child that good bacteria lives peacefully in all of our bodies. According to Actionbioscience.org, millions of bacteria are living in noses, mouths and gastrointestinal tract. In the human mouth alone, there may be up to 25 species of bacteria, and in a milliliter of human saliva there as many as 40 million bacterial cells. These bacteria are alive, and they even breathe. The good bacteria live harmoniously in people's bodies and help it to function properly.
Explain to kids that good bacteria helps keep people alive. According to Actionbioscience, bacteria plays an important role in helping digest food and generate vitamins. When you kill off good bacteria through antiobiotics or other means, this causes an imbalance in which the "bad" bacteria prevails, and conditions, such as diarrhea or yeast infections, may result.
Introduce the "bad guys." Tell your child that bad bacteria are also known as pathogens, and that they might invade the body through air, water, bodily fluids or contaminated surfaces. According to Beyond Books, these bacteria directly attack your body's cells, or they generate toxins that do the damage for them. Some harmful bacteria include anthrax, salmonella, cholera, and campylobacter.
Tell your child that while people fight the bad bacteria, they try to help and replace the good bacteria. According to Actionbioscience, just as people take antibiotics to fend off the bad bacteria that causes illness, they seek certain foods or supplements that contain healthy bacteria. These foods, such as yogurts, dairy products, powders and drinks, may contain lactobacilli and bifidobacterium, which are friendly bacteria that aid in digestion.