Probiotics and Why Bacteria is Good for You

Benefits of the bacteria in our digestive tract, also referred to as gut microflora, have gotten a lot of attention in the scientific community lately—and therefore the professional nutrition and supplement communities as well. The science is fascinating, but what does it really mean for you?

First, what is gut microflora? Also known as gut bacteria, gut bugs, microbiota, and microbiome, gut microflora is the collection of bacteria and other microorganisms that live in your digestive tract. There are about 100 trillion microorganisms in your gut—10 times the total number of cells in your body (remember, these microorganism are not your body, they are separate life forms).

While your microflora are technically not you, they act a lot like an organ of your body. They’re a large part of your immune system; they help break down fiber that nourishes the cells of your digestive tract; and they break down toxins, helping create a healthy balance in the body.

But not all microflora collections are equal. Scientists have come up with three microflora types, sort of like blood types, and some are beneficial while others can set you up for infections, food sensitivities, and overall poorer health.

Can you turn a high-crime “bug city” into a peaceful metropolis? It seems that you can, through probiotic therapy and a fiber-rich diet.

Research suggesting that probiotic therapy can help children with infectious diarrhea and ear infections has been around for a while and used with success. Today, research suggests that improving the balance of your microbiome can positively impact hypertension, weight, diabetes, constipation, and other issues.

Should you take a probiotic?

The answer is, it depends on who you are. Below are three broad categories I encounter in clinical practice.

Definitely worth an experimental trial: If you have digestive symptoms—constipation or diarrhea, irritable bowel or bloating—a course of probiotics is likely to help (especially if you work with a skilled nutritionist who can help you with supportive dietary changes). If you get every cold, flu, and infection that wanders by, probiotics may help strengthen your immune health and make you a little more resistant.

Likely worth a trial: For issues like weight, diabetes, hypertension, cancer, or heart disease, if a good probiotic is not prohibitively expensive for you, a trial to see if it helps these imbalances is worth it—particularly when you weigh it against the years of suffering these conditions may cause.

Probably not necessary; opt for fiber and fermented foods instead: Taking a commercial probiotic is likely not necessary for those who are generally healthy and in reasonable balance, are not working with a chronic disease, and eat a plant-based diet with adequate fiber (the Institute of Medicine of the National Institute of Health says that women need at least 25 grams of fiber and men at least 38 grams, and we all do even better with 50 grams or more). It won’t hurt, but it might not help. Instead, introduce more fermented food—like sauerkraut, tempeh, kombucha tea, and kimchee—into your diet to cultivate a healthy intestinal environment.

Which probiotic should I take?

If you are a good candidate for a trial of probiotics, focus on potency. Look for a probiotic with at least one billion CFUs per dose. If the dose is less, it’s likely the bugs won’t survive your stomach acid to reach your intestines in adequate numbers to help. Several brands have been used with success in clinical trials, including Dannon’s Activia yogurt and DanActive drink, and the supplements Culturelle and Align. It is important to note some of these products do not use organic dairy products, so if that is a factor for you, read the labels carefully. Also, be aware that there are duds out there; recently released a report finding that more than a quarter of the probiotic supplements tested contained 56 percent or less of the potency indicated. A skilled nutritionist will have experience with various brands and can guide you in the right direction.

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Annie B. Kay, MS, RDN, E-RYT 500, C-IAYT, is an author, nutritionist, Kripalu faculty member, and important voice in whole-foods nutrition and yoga.

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