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Probiotics are one of the most commonly used dietary supplements among U.S. adults. While there's growing evidence that probiotics can have beneficial effects on human health, the U.S. Food and Drug Administration has not approved any health claims for probiotics or any probiotics for preventing or treating any health problem.

Get up to speed on what we know about probiotics from NIH's 5 Things to Know About Probiotics and Probiotics: In Depth, which offers information on important topics, including:

  • What's the Bottom Line?
  • What are Probiotics?
  • What the Science Says About the Effectiveness
  • What the Science Says About the Safety and Side Effects

This page also offers notable issues to consider, such as the importance of a pregnant or nursing mother consulting her health care provider (or her child's) if she's considering taking a dietary supplement, such as probiotics, or giving one to her child.

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