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The Basics of Probiotics

Millions use them. But what are the facts?

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What Are Probiotics?

Probiotics are live microorganisms (such as bacteria) that are intended to have health benefits. Products sold as probiotics include yogurt and other foods, dietary supplements, and topically applied skin creams.

Although people often think of them as harmful "germs," many microorganisms help our bodies to function properly. For example, normal intestinal bacteria digest food, destroy disease-causing microorganisms, and produce vitamins. Large numbers of microorganisms live on and in our bodies. In fact, microorganisms in the human body outnumber human cells by 10 to 1. Many of the microorganisms in probiotic products are the same as or similar to the ones in our bodies.

Why Do People Take Probiotics?

People take probiotics in the hope of gaining health benefits, including improved longevity.

What Kinds of Microorganisms Are in Probiotics?

Probiotics may contain a variety of microorganisms. The most common are bacteria that belong to groups called Lactobacillus and Bifidobacterium. Each of these two broad groups includes many types of bacteria. Other bacteria may also be used as probiotics, and so may yeasts such as Saccharomyces boulardii.

How Popular Are Probiotics?

Data from the 2012 National Health Interview Survey show that about four million U.S. adults had used probiotics or prebiotics in the past 30 days. Other than vitamins and minerals, probiotics or prebiotics were the third most commonly used dietary supplement. Their use quadrupled between 2007 and 2012. The survey also showed that 300,000 children ages 4 to 17 had used probiotics or prebiotics in the prior 30 days.

Five Things to Know About Probiotics

Probiotics are available in oral products such as dietary supplements and yogurts, as well as other products such as suppositories and creams. It is important to be aware that the U.S. Food and Drug Administration has not approved any health claims for probiotics. Here are some other things you should know:

  1. Some probiotics may help to prevent diarrhea caused by infections or antibiotics. They may also help with symptoms of irritable bowel syndrome.
  2. Although some probiotic formulations have shown promise in research, strong scientific evidence to support the use of probiotics for most conditions is lacking.
  3. Studies suggest that probiotics usually have few side effects. However, the data on safety, particularly long-term safety, are limited, and the risk of serious side effects may be greater in people who have underlying health conditions.
  4. Probiotic products may contain different types of probiotic microorganisms and have different effects in the human body. The effects also may vary from person to person.
  5. If you are considering a probiotic dietary supplement, talk with your health care provider first. Do not replace scientifically proven treatments with unproven products or practices.
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The Basics of Probiotics / Safety and Side Effects

Winter 2016 Issue: Volume 10 Number 4 Page 22