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Probiotics

A family medicine doctor answers your burning questions about probiotics

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Commonly known as “friendly bacteria,” probiotics have exploded in popularity in recent years. How can we get the best that these tiny organisms have to offer? We asked David Holland, MD, an integrative physician in El Paso, Texas. Holland is board-certified in family medicine and a diplomate of the American Board of Functional Medicine, a discipline that addresses the underlying causes of disease and includes nutritional therapy.

Who needs probiotics?

Dr. Holland: Everyone who has taken antibiotics at any time—even if it was only when they were infants or children—will benefit by taking probiotics. Antibiotics kill helpful bacteria as well as harmful ones, and the negative effects can linger indefinitely unless corrected. Intestinal symptoms such as indigestion, acid reflux, bloating, and constipation stem from an imbalance of gut organisms.

How do probiotics work?

Dr. Holland: To maintain a healthy immune system, it’s vital to keep our intestinal tract healthy because that’s where 70 percent of our immune cells are. Probiotics populate throughout the intestines, where they aid in digestion and produce several beneficial byproducts. These include hydrogen peroxide, which helps control harmful intestinal yeast and reduces disease-causing bacteria in the body.

What should we look for in a probiotic supplement?

Dr. Holland: The degree of benefit that you’ll receive depends on the quality of the probiotic supplement. Make certain that your product guarantees a minimum number of live bacteria per capsule (expressed as “colony forming units,” or CFU) all the way through the expiration date on the bottle. Probiotics come in several different strains, and these strains can provide different benefits. The major ones for intestinal health are Lactobacillus acidophilus, Bifidobacterium bifidum, and Lactobacillus bulgaricus. It’s best to take them together, but if you only take one, my top pick is Bifidobacterium bifidum, as it should be the most populous bacteria in our intestines.

Probiotics can be taken with or without food. But if you have heartburn or indigestion, I recommend taking a chewable probiotic with meals.

What Are Prebiotics?

Prebiotics are close cousins of fiber. Put simply, prebiotics are food for probiotics, the “good” bacteria that live in our gut. Prebiotics preferentially feed these “good guys,” but not the harmful bacteria that can also invade our gut ecology. The problem is that few people eat foods high in prebiotics—raw chicory root, raw Jerusalem artichokes, acacia gum (or gum Arabic), and raw dandelion greens. You can also get prebiotics from raw garlic and raw onions, but you’d have to eat an awful lot (and deal with the unpleasant odor!). Enter prebiotic supplements. Acacia gum and baobab fruit are good supplement choices.

Prebiotics are food for probiotics, the “good” bacteria that live in our gut. Prebiotics preferentially feed these “good guys,” but not the harmful bacteria that can also invade our gut ecology.

—Jonny Bowden, PhD, CNS

Did you know?
If you’re taking antibiotics, it’s best to take probiotics at a different time of the day. And after you’ve completed your antibiotic regimen, take triple the usual dose of probiotics until you feel like your system is back to normal.