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Are probiotics helping you?

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Consuming probiotics – also know as “good” bacteria – via supplements or yogurt has been popularized as a way to maintain gut health. While taking a daily dose of probiotics may not be harming you, it also may not be helping. The idea that every probiotic is good for every disease or condition is oversimplified, according to Catherine Lozupone, an assistant professor of medicine at the University of Colorado School of Medicine.

Lozupone spoke on a panel about the human microbiome, or the bacteria that reside in and on our bodies, that I attended at the Association of Health Care Journalists Conference last month. The panel touched on misconceptions related to probiotics, so I gave Lozupone a call post-conference to learn more.

One misconception Lozupone brought up was the idea that probiotic supplements should be used for “reseeding the good bacteria” missing in a person’s gut. Probiotic supplements often only contain a few species of bacteria, whereas a healthy gut generally has hundreds of species. In addition, the microbes that are abundant in a healthy gut are often different than those found in many supplements. A healthy gut is mostly composed of bacterial species that fall within a two different groups of bacteria: the phyla Bacteroidetes and Firmicutes. One group of bacteria commonly found in probiotics is known as Lactobacillus. While Lactobacillus is a type of Firmicute, it isn’t a type of Firmicute that is typically found in great abundance in a healthy adult gut, according to Lozupone. While Lactobacillus may be helpful for some people in some situations, the idea that everyone needs to repopulate their gut with this “good” bacteria is an overgeneralization.

“I think probiotics have a ton of potential, but different bacteria are going to do different things in different contexts,” Lozupone said. “This notion [of] ‘oh just reseed the good bacteria … they’re good for you’ is definitely very oversimplified.”

But while some general probiotic health claims are ahead of the research, studies do suggest that particular types of probiotic bacteria have potential for specific uses.

For example, Lozupone noted some rodent studies suggest certain microbes might mitigate certain effects of a high-fat diet, which could be helpful to treating obesity and associated health problems.

“There’s just lots of different contexts where the microbiome has been shown to be important,” Lozupone said. Going forward, researchers hope to not only find microbes that have health effects, but also understand why they have these effects. If you’re interested in keeping track of the current research into our body’s bacteria, keep your eye on the NIH’s Human Microbiome Project, an international effort to study the role of the body’s bacteria in our health.

Julianne Wyrick About the Author: Julianne Wyrick has a bachelor’s in biochemistry and is currently a master’s student in the health and medical journalism program at the University of Georgia, where she also writes about science for the Office of Research Communications. Find her on the web at Follow on Twitter @juliannewyrick.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. Bill_Lagakos 4:14 pm 04/29/2014

    “This notion [of] ‘oh just reseed the good bacteria … they’re good for you’ is definitely very oversimplified.”

    “Oversimplified” to say the least! As recently shown in studies on the Hazda microbiome, this is likely very context-dependent… a microbe can be pathological in one person’s gut but beneficial in another’s, depending on their diet.

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  2. 2. Lizette 8:36 am 04/30/2014

    [Student number: 04515596] It is true that microbes can be very good for you due to the fact that they help with digestion, boost your immune system and so on, but not all people experience the benefits of microbes. Some microbes can cause sickness and damage because they attack your bodily cells and systems. This usually happens when they are unbalanced.

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  3. 3. u14029202 2:41 pm 05/1/2014

    I think there is a lot to gain by taking probiotics. Clinical studies have shown probiotics to be of benefit for people with irritable bowl syndrome and a long list of other gastric problems. Controlled trials have also shown that it helps for diarrhoea in children and adults. Probiotics are considered safe, as they are already present in your bowel.

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  4. 4. MBOTES 2:55 pm 05/1/2014


    Problems regarding digesting are very frustrating which causes people to grab probiotics easily. We don’t always realise that it is not the best way to deal with this condition as the bacteria the probiotics contain are not the same as our body’s natural bacteria and therefor also don’t work in the same way.

    Instead of depending entirely on probiotics, can’t we focus on more healthy and natural ways to keep our digestive system working normally? I think we should focus more on our eating habits and examine the possible effects of probiotics first. What if we do not realise damage probiotics cause before it is too late?

    I believe this is a topic everyone will be concerned about, as some people have been relying on probiotics without knowing about the hidden facts. Also, consumers should know what products to trust. I believe further research will create a better understanding regarding our digestive system and the bacteria in it and help us to develop more effective probiotics, suitable for specific individuals.

    We should also take in consideration the risks involved of developing a sort of addiction to bacteria we don’t necessarily need and how it can affect the rest of our body.

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  5. 5. Basil14023131 12:12 pm 05/3/2014

    The use of probiotic supplements are seen to be very important while using antibiotics, as these rid the system of most good microbes and therefore need to be replenished. the fact behind these supplements however, show that they do not contain nearly the number of microbes which our gut contains.Microbes within our body seem to have a lot more health effects than previously recognized. The information in this article is very informative and interesting regarding this matter. [Kyla Balcou 14023131]

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  6. 6. ElneSs 3:41 pm 05/4/2014

    The use of probiotics has become a usual thing in our daily lives that we use to keep healthy. We use it without knowing what effects it has in our bodies. We should stay away from probiotics and rather focus on eating healthy food that will automatically increase your health without having negative effects.

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  7. 7. UnkaDano 11:03 pm 05/6/2014

    My son had a bad gut but that changed when he began taking extra enzymes that he bought at the health food store. I asked him a few months later on a scale of one to ten how well do they work. He said ten! He was holding back tears saying he felt normal for once. I was so happy because his doctors couldn’t figure out what was wrong and I had no idea how much he suffered.

    My wife (no biological relation to my son) has always suffered from IBS. She started taking peppermint oil capsules she bought from our local health food store. She says they are ninety percent effective; sometimes more, sometimes a little less. We are both delighted about it. Like my son, her doctors couldn’t figure out what was wrong either. After their recommendation she had her gallbladder taken out. Now that she has found those peppermint oil capsules we both believe that removing her gallbladder wasn’t really necessary.

    In general I’m delighted because I always believed that most products from health food stores work marginally at best. I’m so glad to be proven wrong.

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  8. 8. EleanorF 10:25 pm 11/13/2014

    While many studies suggest numerous advantages to taking probiotics (ex. improved immune function,decreased atopy etc.) I definitely agree that the media is getting ahead of itself in terms of probiotic health benefits. Most research currently available on probiotics is still in its early stages, and while they do suggest certain advantages to taking probiotics, nothing is quite so conclusive as popular media would lead us to believe.
    Many popular media sources also seem to cite research that is quite dubious in origin, which makes it a challenge to separate fact from speculation when researching probiotics. For example, I read an article online which stated that probiotics facilitated weight loss in obese women, and cited a journal article as its source. However, the journal article was written by three researchers affiliated with a company that produces probiotic foods! The article has the potential to be extremely biased, but those researching probiotics wouldn’t be aware of this bias and take the journal article to be entirely factual. It’s research like this that contributes to the general confusion concerning probiotics and what they do for our health.

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  9. 9. LindaAllen 4:27 pm 02/27/2015

    There’s a growing body of evidence that points to the benefits of probiotics –
    The known benefits of probiotics dates back hundreds of years. Only now is science validating these results. It takes a long time for science to catch up to everything.

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