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When we think of microorganisms in our food, we usually think about bacteria and viruses that cause food-borne diseases. But in some cases, you may actually want live microorganisms in the food you eat.

An example: Probiotics. These live microbes, in some studies, have been shown to provide certain health benefits to people when they’re used in products like yogurt. What can probiotics do for you and where can you get them? And how are they different from “prebiotics” -- another term you might have heard?

Probiotics

Probiotics are live microbes. Occurring in fermented foods, they can help the body sustain a healthy balance of microbes, which can help maintain healthy digestion.

The most common sources of probiotics are dairy foods such as yogurts, some cheeses, and kefir. Probiotics can also be found in other fermented foods like kimchee, sauerkraut, and tempeh.

Some evidence suggests that probiotics may be helpful in supporting the body’s own immune responses, as well.

Prebiotics

Prebiotics aren’t microorganisms themselves. They nurture certain beneficial organisms that live in the gut -- consider them “food” for healthy bacteria. They can be added to cereals, chocolates, spreads, and dairy products.

Prebiotics are also available as over-the-counter supplements.

Probiotics and prebiotics are generally considered to be safe for healthy people. The most common side effects of consuming them are gas and diarrhea, both of which usually decrease over time.