The Pros (and Cons) of Probiotics

Many people hear the word “bacteria” and automatically associate it with disease. But the human body hosts more bacteria cells with beneficial properties, known as microbiota, in our gut, skin, eyes, and nasal canal than it does human cells. Recent studies have made headlines for showing how our “microbiome “ (the ecosystem of our microbiota) is closely linked to our immune system. Gut bacteria are of particular interest for their role in digestive health, as they help break down indigestible plant fibers (think about the fiber found in beans), and help keep you “regular.” Emerging research suggests these bacteria may influence the entire body’s functioning, from autoimmune disorders and skin conditions to obesity and diabetes.

A variety of factors can alter your gut microbiome, including antibiotics, diet, environment, stress, and medical conditions. There are two ways to maintain (or restore) the healthy bacteria in your gut:  consuming probiotics or prebiotics.

Probiotics are essentially those beneficial bacteria found in food or obtained by a supplement. There are hundreds of different strains of bacteria in the human body, but there are a number of common strains that you will see in both foods and supplements, such as Lactobacillus, Streptococcus, and Bifidobacterium. Probiotics have been shown to alleviate some symptoms of irritable bowel syndrome (IBS), restore lost bacteria from antibiotic therapy, and in some cases provide benefit for more serious gastrointestinal disorders such as Crohn’s and colitis.

Yogurt is the most commonly consumed probiotic-containing food. It must contain at least two probiotic cultures, which you will see labeled on a package as “live and active cultures.” Kefir, a fermented, yogurt-like drink, is a much more potent source of probiotics, and many people find it to be more helpful than yogurt. Other foods that contain probiotics include fermented foods like kimchi, sauerkraut, tempeh, and kombucha,

We are also now seeing a slew of packaged foods with added probiotics such as granola bars, cereals, and breads; however, it is unclear whether or not these products retain their potency or contain enough to provide any benefit.

Probiotic supplements have been found to alleviate some symptoms of many gastrointestinal conditions, and they can offer a much higher dose of bacteria (measured in billions of colony-forming units, or CFUs) than most foods. For example, the average yogurt might offer 1 billion CFUs, whereas some supplements claim to offer anywhere from 3 to 50 billion CFUs. More isn’t always better, though. Like other supplements, be wary of strong claims, and read the label carefully for additives, especially if you have any allergies. (Some have been found to contain undisclosed ingredients.) They’re also expensive. The effectiveness depends on the type of probiotic and the symptoms you’re aiming to alleviate. If you are considering taking a supplement to support digestive health, it is best to work with a health professional to determine which brand or strains of probiotic are best for you.

The easiest way to maintain a healthy gut microbiome is by consuming plenty of fermented foods that are naturally rich in probiotics, or by choosing prebiotics, probiotics’ food. The good news is, plant foods such as vegetables, fruits, and beans are filled with the fuel those good bacteria need to thrive. Limiting processed foods may also help, as some studies have shown that diets filled with processed foods can alter the healthy bacteria in your gut.

The market for probiotics will continue to grow, especially if the research links them to other benefits. Remember though, if you keep your gut happy with a healthy diet, and don’t have any medical conditions that would alter your gut microbiota, you probably don’t need a supplement. And, as a good rule of thumb — reach for food, not pills, first!