Could Probiotic Supplements Actually Be Bad For You?

Probiotics have been the buzzword for the last decade. Everywhere I turn there are news stories or studies about their myriad health benefits. So, imagine my surprise when I came across an article about the problems of probiotic supplementation entitled “‘Good’ bacteria? New research suggests probiotics might actually be bad.” The article proceeded to explain how supplementation with probiotics might be useless or may actually damage your health. Intrigued, I continued reading.

The article mentioned two studies. In the first one, published in the journal Cell, researchers gave 25 volunteers a probiotic supplement containing 11 strains of probiotics for one month. After testing stomach and intestinal samples at the end of the study, they found that the bacteria had either gone through their bodies or were overtaken by other bacteria.

The second study, published in the same journal, assessed the post-antibiotic probiotic supplementation of 46 people. The researchers found that the probiotic supplements delayed the regrowth of the bacteria that had been destroyed by the antibiotics.

Before you assume that probiotics might actually be bad for you, as the story suggests, let’s consider a few other facts.

Both of the study samples are extremely small and don’t warrant drawing any type of blanket conclusions about probiotics being useless or, worse, harmful to people. Even a cursory review of the latter study showed that the scientists were recognizing the value of probiotics but not used as a one-size-fits-all approach the way that most doctors recommend them. I totally agree with that. One-size-fits-all doesn’t work in virtually any aspect of life. Why would probiotics be any different? The correct way to take probiotics is to use formulations of research-supported strains for particular health purposes.

Considering that there is a whole host (pun intended) of other studies showcasing the many health benefits of taking probiotics, including as a treatment for antibiotic-associated health problems, I would expect that these studies be considered prior to making claims that probiotics may be bad. I should know, I reviewed thousands of studies for the two books I wrote on probiotics: The Cultured Cook and The Probiotic Promise. Among them include studies with larger population samples. For example, one study in the Journal of Clinical Gastroenterology found that supplementation with probiotics was highly effective at alleviating the effects of antibiotics.

Another study published in the journal BMJ Clinical Research found that a blend of probiotics L. casei, L. bulgaricus and S. thermophilus cut the incidence of antibiotic-associated diarrhea by almost two-thirds. That would likely be considered a miracle drug in the pharmaceutical industry if it was patentable.

Scientists in Finland conducted another study that was published in the World Journal of Gastroenterology, in which they tested the effectiveness of probiotic supplements to 1) prevent antibiotic-related diarrhea; and 2) to assess the rate of C. difficile infections and the resulting diarrhea from antibiotic use. They found a direct link between the highest doses of probiotics and the lowest incidence and shortest durations of antibiotic-induced side-effects like diarrhea. As a bonus, they found that those supplementing with probiotic supplements had fewer fevers, abdominal pain and bloating.

Before you believe the apparently new hype that probiotics are useless or dangerous, it is important to consider a few more things:

1)     Your bowels are packed with probiotics that are needed to keep you alive so claiming probiotics are harmful is both disturbing and dangerous. You couldn’t live without them.

2)     Like all bacteria, good or bad, they fight for space and nutrients. In your bowels, that means they battle each other for attachment to your intestinal walls and for the nutrients you provide them with through the food you eat. Eat a lousy diet and you’ll feed the harmful bacteria, but if you eat a diet full of fiber and natural sugars from fruit you’ll feed the beneficial ones.

3)     Broad-spectrum probiotic supplements that are formulated without the consideration of the interactions between bacteria simply won’t yield the health-promoting results that have been achieved in thousands of studies. It’s not just a matter of take as many different types as you can and you’ll get great results. You might not get any beneficial results if you take this approach. But, that doesn’t mean that probiotic supplements are useless or dangerous. Far from it.

Research-supported formulas can save lives. There are many studies showcasing their benefits for everything from antibiotic-induced side-effects to fighting superbug infections that often kill people, giving probiotics the potential to, not just improve health, but save lives.

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Dr. Michelle Schoffro Cook, PhD, DNM is the publisher of the free e-newsletter World’s Healthiest News, the Cultured Cook, co-founder of BestPlaceinCanada, and an international best-selling and 20-time published book author whose works include: Be Your Own Herbalist: Essential Herbs for Health, Beauty, & Cooking.  Follow her work.



Peggy B
Peggy B4 months ago


Nellie K Adaba
Nellie K Adaba5 months ago

Great to know that I stopped using Probiotic products (pills, skin, yogurt, etc). Scary.

Elizabeth M
Past Member 5 months ago

Thank you Michelle noted

Sue L
Sue L5 months ago

I'm guessing that for probiotics to work that a doc would have to determine what your particular gut needed. Just taking any old supplement doesn't seem like the right approach.

Victoria P
Victoria P5 months ago

Thank you

Janis K
Janis K5 months ago

Thanks for sharing.

Martin H
Martin H5 months ago

think I will abstain.

Debbi W
Debbi W5 months ago

I can't take probiotics. They cause gastric distress.

Teresa W
Teresa W5 months ago

Irene is right.

Mark T
Mark T5 months ago