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What Are Probiotics and Should I Take Them?

These Microorganisms Could Help Your Health


Updated June 04, 2014

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Probiotics are live organisms, mostly bacteria or yeasts, that are helpful to their hosts (in our case, people). Usually when people hear about bacteria in their bodies, they assume that there is some kind of harmful infection present. In fact, we have huge amounts of helpful microorganisms in our bodies, especially in our gut and intestines.

Some of the most common probiotics are in the Lactobacillus family (L. acidophilus, L. casei, L. rhamnosus, L. bulgaricus, L. plantarum, L. helveticus) or the Bifidobacterium family (B. bifidum, B. longum, B. breve, B. infantis).

Probiotics may contribute to healthy aging by improving immune function (especially mucosal immunity in the digestive system, improving mineral absorption from food and supplements and helping or preventing digestive problems.

What Are the Benefits of Probiotics?

There are many reasons someone may want to take probiotics, as they are used both to treat problems and to prevent others. However, pretty much across the board, more research needs to be done in order for any of these benefits to be "proven," as studies on probiotics have been too small to make scientific conclusions and not very rigorous. However, patient reports and anecdotal evidence certainly points to the anecdotal fact that some people are feeling positive effects from taking probiotics for certain conditions.

Some conditions that probiotics may be able to help are:

  • Lactose intolerance
  • Digestive problems associated with antibiotics
  • Helicobacter pylori
  • High blood pressure
  • Yeast infections
  • High cholesterol
  • Constipation
  • Irritable bowel syndrome and colitis

Research has also shown that probiotics may be effective in preventing the following:

  • Colon cancer
  • Infections due to a weakened immune system

How Are Probiotics Taken?

Probiotics can be taken several ways, including:

In yogurt or food: Eating yogurt is the primary way that people are exposed to probiotics. They can also be found in kefir (a yogurt-type drink), buttermilk and some pickled vegetables. Compared to other forms of probiotics, these foods provide a relatively low concentration of organisms.

As a powder: There are also powders that are comprised of probiotics (mixed with a filler) that can be mixed into liquids or food and consumed. Many of these need to be refrigerated.

In capsule form: It is common to find some probiotics (especially Lactobacillus acidophilus or Bifidobacterium bifidus) in capsule form. Many of these need to be refrigerated.

In "pearl" form: Looking much like very small, round pills, probiotic "pearls" are coated so that they pass through your stomach and dissolve once they are in your intestinal tract. This is supposed to be important, as stomach acid can kill the majority of the helpful microorganisms before they get to the intestines, where they can really work.

Who Should NOT Take Probiotics?

If you are on any type of immunosuppressant medication or are immunosuppressed (if you have HIV, for instance), you will want to ask your doctor about probiotics before you take them in any form. There don't seem to be any documented drug interactions with probiotics.

The Bottom Line

As far as I can tell, probiotics have lots of potential benefits and very few drawbacks, though more research still needs to be done. I will consider adding them to my regimen, especially for those times when I am prescribed antibiotics or am experiencing any sort of digestive problems.


An Introduction to Probiotics. National Center for Complementary and Alternative Medicine of the National Institutes of Health.

Iannitti T, Palmieri B. Therapeutical use of probiotic formulations in clinical practice. Clin Nutr. 2010 Jun 22. [Epub ahead of print]

Sullivan A, Nord CE. Probiotics and gastrointestinal diseases. J Intern Med. 2005 Jan;257(1):78-92.

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