Got a tummy ache? Have a bout of diarrhea? Want to feel less sluggish or dial down systemic inflammation? You might be used to reaching for probiotics. These supplements have been marketed as an over-the-counter cure-all for a variety of conditions, as well as a daily general health booster for just about anyone. These days, you can purchase an extraordinary array of probiotic supplements online and at your local health food or grocery store.
Despite their positive reputation and widespread availability, the science around probiotic supplementation isn’t as solid as it might seem. According to gut health experts, probiotics may have benefits for specific health issues, but they’re not necessarily a wise choice for the general population.
Read on for what to know before you buy probiotics.
What are Probiotics?
Probiotics are live bacteria similar to those found in your digestive tract. The World Health Organization defines them as “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.” This is why you’ve probably heard them referred to as “friendly” or “good” bacteria.
As a dietary supplement, probiotics can be purchased in the form of pills, powders, syrups, teas, and tinctures. Most supplements not only contain enormous amounts of these bacteria (typically in the billions), but also several different strains of bacteria.
Probiotics occur naturally in numerous foods, too, most of which are fermented. Yogurt, kimchi, sauerkraut, and kombucha, for example, all harbor sizable amounts. (However, it’s worth noting that not all fermented foods contain these good bacteria.)
What Does the Research Say?
Since probiotics are considered beneficial bacteria, you may wonder: can you really go wrong by adding them to your supplement regimen? Here’s what the evidence shows.
Probiotics Don’t Appear to Provide General Health Benefits
Although personal anecdotes from friends or a sales pitch from your local health store employee may sound convincing, experts say the evidence simply doesn’t support popping probiotic pills for general good health. “Research suggests that those that are generally healthy do not attain a benefit from probiotic supplements,” says dietitian Suzie Finkel, RD, who specializes in digestive health.
In fact, a 2019 review of 45 studies on probiotic supplementation in healthy adults concluded that the beneficial bacteria may have benefits in specific populations, but general usage requires further investigation.
Rather than serving as a panacea for general health issues like energy levels, inflammation, or bowel regularity, it appears probiotic supplements have more to offer for people with specific health conditions.
“Demonstrated benefits of specific probiotics (as in, specific strains of bacteria) are specific to certain types of conditions, not for general health.” — Suzie Finkel, RD
Probiotics May Cause GI Distress
Many people turn to probiotic pills to ease digestive distress caused by antibiotics or a stomach bug—and it’s true that some research supports the use of probiotics for digestive complaints.
According to the National Center for Complementary and Integrative Health, probiotics could help prevent antibiotic-associated diarrhea. But researchers still don’t know which species and strains are helpful and which ones are not.
In fact, grabbing any old “friendly bacteria” off the shelf could actually exacerbate digestive issues, not help them. “Adding an external bacteria pill that is not a good fit for you can cause unwanted gastrointestinal symptoms, or worsen symptoms you’re already experiencing,” says Finkel. “It is important to work with a healthcare provider that is well-versed in the latest research for these supplements.”
Probiotics May Not Be Worth the Money
Some probiotic supplements aren’t particularly expensive, but others can cost a pretty penny. According to Finkel, shelling out tons of cash for a designer probiotic might not bring the return on investment you’re hoping for.
“Contrary to what most would think, I often tell patients to remove probiotic supplements from their regimens, and I do see people feel better without them more often than not!” she says. “Or at the very least, they feel exactly the same and get to save a bunch of money.” Since so many foods are naturally packed with probiotics, it may be smarter for your wallet and your health to get probiotics from your diet, rather than pills.
Probiotics May Benefit Certain Health Conditions
While research doesn’t seem to support probiotics for general health, a growing body of evidence shows that some strains could make a difference for people with certain health conditions. These include Clostridium difficile infection and inflammatory bowel disease.
Clostridium Dificile Infection
If you’ve ever come down with a clostridium difficile (aka “c. diff”) infection, you know the suffering this bacterial invasion can cause. C. difficile infection is characterized by mild to severe diarrhea that can be resistant to treatment. Fortunately, probiotic supplementation may help!
A large meta-analysis that assessed 31 studies on over 8,600 patients found “moderate certainty evidence” that probiotics were effective for preventing C. difficile-associated diarrhea. However, research has yet to determine which probiotics are most useful for treating this condition (and how long they should be taken).
Inflammatory Bowel Disease
Inflammatory bowel disease (IBD) is an umbrella term that encompasses two intestinal autoimmune conditions: Crohn’s disease and ulcerative colitis. Numerous studies have looked at how probiotics might reduce IBD symptoms like diarrhea, fatigue, and weight loss.
Though researchers caution that more evidence is needed, some studies offer a ray of hope for IBD sufferers—especially those with ulcerative colitis. A 2014 review, for example, found that probiotics, prebiotics, or synbiotics could help ulcerative colitis go into remission.5 It didn’t find the same for Crohn’s disease, however. Meanwhile, other studies have concluded that the benefits of probiotics for IBD are unclear.67
How to Incorporate Probiotics in your Diet Naturally
Rather than purchasing pricey supplements that may not be effective, you can find excellent sources of probiotics in your home kitchen. The following foods are rich in probiotics:
- Yogurt
- Kefir
- Sauerkraut
- Miso
- Sourdough bread
- Kimchi
- Tempeh
- Kombucha
To help good bacteria flourish in your gut, it’s also useful to give them “food” to promote their growth. You can do this by eating foods high in prebiotic fiber, such as apples, garlic, onions, asparagus, bananas, beans, and nuts.
Though it’s always a good idea to incorporate these nutritious whole foods into your diet, don’t expect them to be a miracle cure for any health condition. “Fermented foods contain beneficial bacteria, but we don’t have evidence of their ability to revolutionize the gut as one might be led to believe,” says Finkel. “I tell my patients that if they like these foods they should include them in their diet; many of them are plants and offer the added benefit of nourishing the microbiome with fibers.”