Get your score

Should everyone take a daily probiotic?

What you hear: “Everybody should take a probiotic every day to keep their gut healthy.”

What the studies found

A review of 45 trials in healthy adults found probiotics briefly raised levels of the bacteria in the product but did not cause lasting changes to gut bacteria. A 2024 expert review found good evidence only for specific uses, such as during antibiotics, and not enough to recommend probiotics for everyone. The clearest benefit is preventing diarrhea from antibiotics: in a Cochrane review of 33 trials in children (6,352 kids), it hit 8% of those on probiotics vs 19% without, and a pooled analysis of 15 adult trials (7,427 people) found 40% fewer cases. The American Gastroenterological Association advises using probiotics for Crohn's disease, ulcerative colitis and irritable bowel syndrome only within research studies. In a small study in mice and people, taking probiotics after antibiotics actually slowed the return of the gut's own bacteria.

Take care: Generally safe for healthy people, but the risk is higher for those who are very ill or have weak immune systems, and premature babies have had severe infections.

What you could do

Skip the daily habit if you feel fine; consider a well-studied probiotic when taking antibiotics, and eat fiber-rich and fermented foods.

Get your longevity score and see which everyday habits make the biggest difference for you.

Not medical advice. General information from published studies, not a diagnosis or a treatment plan. Talk with your doctor before starting a supplement or changing a medicine, especially if you are pregnant, take other medicines or have a health condition.

How we judged it

Partly true: Some truth, but oversold as usually said. We judge the claim as it is usually said online, not the habit itself. Trials assign people at random, so they can show cause; observed studies follow people and show a link, not proof. Last checked: October 2026.

The studies, in their own words

1. Khalesi et al. Eur J Clin Nutr 2019

   However, this review failed to support the ability of probiotics to cause persistent changes in gut microbiota, or improve lipid profile in healthy adults.

2. Merenstein et al. Adv Nutr 2024

   However, we did not find a sufficiently high level of evidence to support unconditional, population-wide recommendations for other preventive endpoints we reviewed for healthy people.

3. Guo et al. Cochrane Database Syst Rev 2019

   After 5 days to 12 weeks of follow-up, the incidence of AAD in the probiotic group was 8% (259/3232) compared to 19% (598/3120) in the control group (RR 0.45, 95% CI 0.36 to 0.56; I² = 57%, 6352 participants; NNTB 9, 95% CI 7 to 13; moderate certainty evidence).

4. Wanyama et al. Prz Gastroenterol 2025

   Pooled analysis favored probiotics, reducing AAD incidence by 40% (RR = 0.60, 95% CI: 0.43-0.82).

5. Su et al. Gastroenterology 2020 (AGA guideline)

   In adults and children with Crohn’s disease, we recommend the use of probiotics only in the context of a clinical trial.

More claims, checked

• Partly trueArtificial sweeteners are worse than sugar
• Partly trueEggs raise cholesterol and cause heart disease
• Partly trueCoffee helps you live longer
• Not provenCarnivore diet
• Not provenGlucose monitor without diabetes
• Not provenCold plunges and ice baths

See all 50 claims