How do probiotics work?

Roshini C. Rajapaksa, MD
Probiotics, the good bacteria that help maintain the integrity of the digestive tract, work to protect our intestinal lining and digest some nutrients. Watch me explain how probiotics work to keep the gut healthy.
Probiotics are "good bacteria" that are the same as or similar to the bacteria naturally present in healthy bodies. For example, you normally have a thriving population of bacteria in your gut, which help you digest food. Probiotic supplements can increase your levels of these good-for-you microorganisms. This is especially helpful if you have been taking antibiotics, which can kill beneficial bacteria along with ones that cause disease.

Probiotics can help keep you healthy in several ways. When they are abundant in your body, it's harder for bacteria that cause illness to get a foothold. Probiotics may also produce compounds that help keep illness-causing bacteria from thriving. Finally, probiotics may stimulate your immune system.
Eva B. Cwynar, MD
Internal Medicine
One way to help manage problems of the gut is by supporting the intestinal flora through the use of probiotics. Probiotic literally means "for life." The World Health Organization (WHO) defines probiotics as "live microorganisms, which when given in adequate amounts, confer a health benefit on the host." In other words, probiotics are living bacteria that are similar to the friendly bacteria found in the human intestinal system. They live symbiotically in the gut, meaning they form a give-and-take relationship where they help us fight off the bad guys in return for a warm place to live. There are a few common probiotics, such as Saccharomyces boulardii, that are yeasts, which are different from bacteria.

Probiotics work by constantly adjusting the intestinal immune environment to help correct the balance between beneficial and harmful bacteria and to prevent disease-causing bacteria from attacking and colonizing the gut. They restrict the overgrowth of harmful bacteria and promote the growth of helpful bacteria, which in turn enhances digestion and absorption of nutrients.
The Fatigue Solution: Increase Your Energy in Eight Easy Steps

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The Fatigue Solution: Increase Your Energy in Eight Easy Steps

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.