Ask a nutrition student: Not all bacteria are bad

Stacey Arnold

I’ve seen the words probiotic and prebiotic on supplements at the pharmacy and flashed across food labels. What do they mean? Do I need to be taking a probiotic pill every day or is this just another fad?

— Anti-biotic?

Believe it or not, there are some good bacteria in your body — hence the hype around probiotics and prebiotics. Before I get into those products, however, let me help you digest some basics of bacteria.

Stomach this: Your body contains 10 times more microorganism cells than body cells, according to Genes and Nutrition journal. These bacteria cover our skin, mouths and lungs. But your gastrointestinal tract — responsible for the absorption and digestion of food — is where they most densely populate.  

Although the word bacteria conjures up thoughts of cold and flu season and gross bathrooms, the kind found in your digestive tract, gut microbiota, are actually beneficial. These good bacteria help digest food, produce vitamin K and vitamin B12 and protect your body from disease by boosting the immune system.

The quantity and composition of gut bacteria differs from person to person. Genetics, environmental factors and diet all influence your intestines’ bacterial community. But doctors have seen disturbances in microbiota in people with bowel diseases, diabetes, certain cancers and obesity, according to Genes and Nutrition.

And what’s even more interesting is researchers are looking into the potential connection between gut microorganisms and psychological conditions such as stress, autism and Alzheimer’s disease, according to the Journal of Physiology.

Now that I’ve covered some microbio 101, let’s get back to probiotics. Probiotics are food or supplement products that contain the good bacteria found in your gut. As a germaphobe, I never thought I would be promoting the intake of bacteria, but when consumed, probiotics can help repopulate and rebalance gut microbiota, according to the Academy of Nutrition and Dietetics. 

Probiotics can be found in products such as yogurt, buttermilk, kefir and sourdough bread as well as non-dairy sources such as miso, tempeh, sauerkraut and kimchi — great ways to boost your gut health and try some adventurous foods!

Prebiotics on the other hand (notice the different prefix) are foods that probiotics feed on, and they support the growth and health of gut bacteria. Fructooligosaccharides and inulin are fancy words for two types of prebiotics that are found in foods such as asparagus, onions, whole-wheat products and bananas.

If you’re looking to gain your pre- and probiotics through supplements instead of foods, be cautious; not all supplements are created equally. The quality and ingredients may be different than expected, according to the Academy of Nutrition and Dietetics. And if you are eating a balanced diet, supplements usually aren’t necessary. 

Researchers continue to find out just how helpful probiotics and prebiotics are. If you feel you need specific advice regarding gut health or you are experiencing gastrointestinal problems, speak with a registered dietitian. For the general population, I say skip the supplements and have food bring in the beneficial bugs. Cold and flu season may be upon us, but ironically, you may stay healthier by boosting your (good) bacteria intake.