What are probiotics?

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. The word probiotic is often used incorrectly to refer to any live culture, such as those used in traditional fermented foods — but an international group of scientists convened by ISAPP agreed that the term should be restricted to microorganisms that have been properly defined and shown to provide a health benefit.

Your body contains 38 trillions of microbes that make up your microbiota and assist in keeping you healthy. Probiotics can play a supportive role in these processes. Probiotic bacteria may be found in a variety of different foods, such as some yogurt and infant formulas, and in dietary supplements. Probiotics are also used in some pharmaceutical products, non-orally consumed products (such as tampons and skin creams), and animal foods and supplements.

What can probiotics do for health?

Research has shown that probiotics can support health in a variety of different ways. In general, they may assist with your immune function, aid your digestion, keep harmful microorganisms in check, produce vitamins, and aid in nutrient absorption. Specifically, there’s evidence that certain probiotics can:

  • Reduce antibiotic-associated diarrhea
  • Treat infectious pediatric diarrhea
  • Improve some digestive symptoms, including those caused by mild to moderate irritable bowel syndrome
  • Help manage symptoms associated with poor digestion of lactose
  • Reduce colic symptoms in infants
  • Decrease some common infections, including those of the respiratory tract, gut, and vaginal tract

When you’re choosing a probiotic, it’s important to remember that not all probiotics have the same effects. Microbes used as probiotics are identified by their genus, species and strain designation. Different strains of even the same species of probiotic may confer different health effects. So you need to pick a strain that has been studied and shown to give the benefit you want. Amount also matters, so be sure the product contains the level of probiotics needed for the desired health benefit.

See here for resources that can help you find a probiotic product to address your needs.

Will probiotics work for me?

Like all strategies for promoting health, many factors unique to you may influence what works for you and what doesn’t. That’s true for probiotics, too. Any specific probiotic strain might not work for everyone. Scientists think the factors that might influence whether a probiotic works for you could include your unique diet, the existing microbes in your digestive tract, what medications you may be taking, and your personal physiology. One strategy for figuring out whether a probiotic is right for you is to try a product for about a month. If you don’t see the benefit you are looking for, then perhaps it’s not the right one for you. Prebiotics and some fermented foods are alternative ways to address health through the gut.

Are probiotics safe?

Probiotics are safe for most people, but talk to your doctor first if you suffer from an immune disorder or short bowel syndrome, or have a serious illness. You should also check with a medical professional before giving probiotics to an infant.

Amounts Matter with Probiotics

Make sure your product contains the level of probiotics needed for the intended health benefit.

Check out this infographic, “Deciphering a probiotic label”, on how to read probiotic labels to find out how many live microorganisms (measured in colony-forming units) are present.

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Should Healthy People Take Probiotics?

This infographic, called “Probiotics for healthy people”, explains the scientific evidence for probiotic use in healthy individuals.

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What’s Important When Choosing a Probiotic?

There are many probiotic products on the shelves—read this handy “Probiotic checklist” for choosing one that meets your needs.

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Know the Real Science

Those who talk about probiotics don’t always get their facts straight—see our infographic called “Probiotics: dispelling myths”. Here’s a summary of how probiotics are different from the live cultures in fermented foods.

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Probiotics: the Cheat Sheet

See this infographic called “Probiotics” for an overview of exactly what probiotics are, where to find them, and what they can do for your health.

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ISAPP Videos

Check out these ISAPP educational videos to answer the most common questions about probiotics.

What is a probiotic?
Health benefits of probiotics
Are all probiotics the same?
How to choose a probiotic

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