Probiotics and upper respiratory infections
Cochrane finds fewer infections with low-certainty evidence. Effects are strain-specific and products vary.
Education only, not medical advice. Talk to your clinician before starting a supplement, especially if you are pregnant, take medication or have a condition.
Evidence grade: C (A strong, B good with gaps, C limited or mixed, D early)
What the review found
The 2022 Cochrane update found probiotics probably reduced the number of people with at least one upper respiratory infection, but the certainty was low to moderate because of trial quality and differences between strains [1].
Caveats
Results for one strain do not transfer to another, and products may not contain what the label says. People with weakened immune systems and premature infants can develop serious infections from probiotics [2].
Sources
- Zhao et al. 2022, Cochrane. doi.org/10.1002/14651858.CD006895.pub4
- NCCIH, Probiotics: what you need to know. www.nccih.nih.gov/health/probiotics-what-you-need-to-know
DOIs verified against Crossref and official pages checked on 2026-10-15.