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  • Friendly Neighborhood Bacteria

Published on November 20, 2013

Friendly Neighborhood Bacteria

Avera Sacred Heart Hospital
Sara German, RD, LN

Whether you like it or not, bacteria are everywhere: on your skin, in your food, and inside your body. For the most part, actually, this is a very good thing. We hear about bad bacteria on the news (MRSA, salmonella and E. coli come to mind), but these nasties are the exception, not the rule. Most of the bacteria we come into contact with aren’t harmful, and can even improve our health.

The human body is full of microbes, mostly in the form of bacteria. The large intestine is a diverse environment, containing up to 500 different species of bacteria and literally hundreds of trillions of organisms (that’s one followed by twelve zeros).   These bacteria aren’t parasites, or even free riders; instead, they’re more like business partners. Imagine two neighborhoods. One neighborhood is barren, its streets lined with empty, abandoned houses. The other neighborhood is a thriving community, filled with families and businesses. Which one is going to be more susceptible to gang infiltration? In the same way, the good bacteria in your intestines make it harder for pathogens – the bad bugs – to establish themselves and cause illness. The good bacteria also act as neighborhood crime watch groups, assisting and strengthening the “police” – your body’s immune system.

Although the bacteria in your gut play an important role in your health, not all bacteria have the same health benefits. Specific strains of microbes that have been studied and shown to have health benefits in humans are called “probiotics.”  One particular probiotic, for instance, may help alleviate the symptoms of irritable bowel syndrome, while another may be more effective at treating antibiotic-associated diarrhea. That’s not to say that other strains of bacteria aren’t good for you, but only probiotics have proven benefits. There is evidence supporting that probiotics can be helpful in treating infant diarrhea, antibiotic associated diarrhea and C difficile, irritable bowel syndrome symptoms, pouchitis, and ulcerative colitis. Some probiotics may help enhance the immune system. When using probiotics, it is important to choose the correct strain and dosage for the most benefit.

How can you add microbes to your diet? In the United States, most ingestible bacteria are found in fermentable dairy products, including as yogurt, kefir (a yogurt-like drink), and certain cheeses. To choose a product with live bacteria, look for the words “contains live and active cultures” on the packaging. Other fermented foods, such as pickles, sauerkraut, kimchi, and tempeh, may contain live bacteria, but in most cases these are killed during the manufacturing process.

If you are looking specifically for probiotics, brand names are important – different brands of yogurt contain different combinations and strains of bacteria, and not all of them contain probiotics. Some brands of yogurt that contain probiotics include Activia and DanActive. (Note: the author does not endorse these products. Additionally, even if a yogurt does not contain probiotics, it contains many other important nutrients.) You can also take probiotic supplements, which come in a variety of forms, including powers, tablets or capsules.

Another way to support good bacteria in your gut is to feed them. Bacteria thrive on dietary fiber, which is found in whole grains, beans, nuts, fruits, and vegetables. Coincidentally (or maybe not), these foods are all known to have health benefits. What’s good for you is also good for your bacteria!