Probiotics & Prebiotics

A woman with an "out of order" sign written on her belly

The dynamic duo works to keep you healthy!

The health benefits of probiotics—the beneficial bacteria found in live-culture yogurt, fermented foods, and dietary supplements—are well known. From resolving diarrhea to bolstering immunity, probiotics contribute to health in many ways.

What Are Prebiotics?

Not so well-known? Compounds called prebiotics. Prebiotics, dietary fibers that humans can’t digest, serve as food for probiotics. Consuming more prebiotics will contribute to flourishing colonies of good bacteria in your system.

Most prebiotics fall into the category of carbohydrates, with the main prebiotics being inulin, fructo-oligosaccharides (FOS), and galacto- oligosaccharides (GOS). These prebiotics, when consumed in functional foods or taken in dietary supplement form, contribute to the growth of healthy bacteria in the intestines.

Boost Your Immunity with Probiotics and Prebiotics

The common cold and similar respiratory viruses back off when faced with the power of probiotics. One six-month study found that overweight and older adults who took a daily probiotic supplement had a 27 percent lower incidence of upper respiratory tract symptoms compared to a group that received a placebo. The most significant effects were seen in people 45 or older, as well as those with obesity.

Lead researcher Benjamin Mullish, MD, said the study provides "further evidence that the gut microbiome has a complex relationship with our various organ systems. It doesn't just affect how our gut works or how our liver works, it affects aspects of how our whole body works."

Immune function tends to dwindle as people age, yet prebiotic supplements (specifically GOS) also bolster immunity in older people.

Balance Your Gut Flora for Appetite Regulation

Scientists are learning that dysbiosis—an imbalance of gut flora caused by too few healthy bacteria or an overgrowth of bad bacteria and yeast—may negatively affect weight. Probiotics and prebiotics both help the gut return to a more balanced state. Appetite, caloric intake, and body mass index all tend to go down when people take prebiotics.

Focus & Improve Your Mood with Probiotics

A typical Western diet high in saturated fats and sugars can negatively affect the mind. This diet-cognition link is thought to relate (at least in part) to out-of-balance gut bacteria. It may seem surprising that gut health influences mental clarity, but the connection has been well established in research. In fact, when probiotics and prebiotics get added into the diet as supplements, thinking processes can improve. Mood receives an uptick from prebiotics, which are associated with less anxiety, depression, and stress. When healthy volunteers supplement with prebiotics for three weeks, their anxiety—as measured by cortisol levels—goes down.

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Victoria Dolby Toews, MPH

Victoria Dolby Toews, MPH, is an evidence-based, integrative medicine journalist with more than 20 years of research and writing expertise, She received her Master of Public Health from OHSU-PSU School of Public Health.

She is the author or co-author of numerous books, including Life After Baby (2012), The Green Tea Book, 2nd edition (Penguin, 2008). User’s Guide to Healthy Digestion (Basic Health Publications, 2004), The Soy Sensation (McGraw-Hill, 2002), User’s Guide to Glucosamine and Chondroitin (Basic Health Publications, 2002), The Common Cold Cure (Avery, 1999), and The Green Tea Book (Avery, 1998).

Her work was recognized for excellence as a 2001 finalist for the Maggie Awards (Western Publications Association award honoring editorial excellence in magazines west of the Mississippi River).