Research

Mixed

Specific probiotic strains reduce the frequency, severity, and duration of upper respiratory tract infections (URTI) in athletes, particularly under conditions of high training load or environmental stress.

If you are an athlete prone to colds, look for a probiotic with a specific strain that has been studied for immune health (e.g., Lactobacillus rhamnosus GG). Do not buy generic 'probiotic' blends without strain identification. Ensure the product lists the specific genus, species, and strain on the label.

GoodSupportsHIGH confidence
In an athletic population, specific probiotic strains can reduce the number of episodes, severity and duration of upper respiratory tract infections.
Ralf Jäger et al. · Journal of the International Society of Sports Nutrition · 2019

Why this rating

Based on a systematic review of multiple human studies, though strain specificity limits generalizability.

Source

International Society of Sports Nutrition Position Stand: Probiotics

Ralf Jäger et al. · Journal of the International Society of Sports Nutrition · 2019

DOI 10.1186/s12970-019-0329-0

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Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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