Gut Reaction

But picking the right one isn’t always easy. There are a ton of different bacteria and various strains of each. Plus, the number of products on the market has increased tenfold in less than a decade, so navigating the probiotics aisle can be gut-wrenching in its own right.

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We asked The Vitamin Shoppe’s probiotic expert Eric Cohen to guide us through the basics.

What you’ve got: Irritable Bowel Syndrome (IBS)
What to look for: Jarrow Ideal Bowel Support provides a clinically-studied strain to address bowel health, according to Cohen. Also check out Renew Life Ultimate Flora Critical Colon 80 Billion.

What you’ve got: Diarrhea
What to look for: Saccharomyces boulardii is a probiotic yeast that can deter bacteria from adhering to the intestinal lining, preventing over-proliferation. It is hearty enough to survive splashes of stomach acid. Florastor, a popular supplement capsule, has yeast found naturally on the skins of some tropical fruits.

Some probiotics require refrigeration to keep the microbes kicking. Since traveler’s diarrhea is common, Cohen recommends packing a probiotic that can be stored at room temperature when you’re away from home. He suggests The Vitamin Shoppe Ultimate 10 Probiotic, Dr. Ohhira’s Probiotic Original Formula, Jarro-Dophilus or UAS Labs Probioplus DDS.

What you’ve got: Yeast infection
What to look for: For a happy, well-balanced vagina, there’s Garden of Life’s Raw Probiotic for Women, ReNew Life Ultimate Flora Vaginal Support and Jarrow’s adorably-named Fem-Dophilus. These formulas offer additional benefits for the urinary tract.

What you’ve got: A prescription for antibiotics
What to look for: “Antibiotics can rapidly deplete the balance of friendly intestinal flora, which may result in digestive issues,” explains Cohen. He says that, in order to more quickly restore your microfloral friends, you should opt for products with a CFU of 50 billion or higher. CFU stands for colony-forming units, a measure of how potent the probiotic is.  Some examples: The Vitamin Shoppe Ultimate 10 Probiotic 50 Billion and Nature’s Way Primadophilus (90 billion or 100 billion). Florastor could come in handy here, too, since yeast is impervious to antibiotics, so it won't be counteracted by your Rx.

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With new products hitting shelves constantly—and the Food and Drug Administration wavering on whether to regulate probiotics as a food or a drug—the road to the right probiotic for you has as many twists and turns as your small intestine. Richter stresses the importance of talking to a representative at a health food store or supplement shop to discuss your particular symptoms, history and personal preferences.

Then open wide and give back to your bacterial brethren who do so much for you without ever expecting a thank you.