Regular ice bath immersion improves immune function in healthy adults.

Is it true that regular ice bath immersion improves immune function in healthy adults?

Partly. A 2025 systematic review and meta-analysis of cold-water immersion in healthy adults found no significant effect on immune function immediately or one hour after immersion, though narrative synthesis noted a 29% reduction in sickness absence among cold-shower participants. A separate review of cold-water immersion at or below 14°C reports only context-dependent modulation of immune markers, and a 2022 review notes the immune-boosting claim rests largely on popular literature and anecdotal cases.

Verdict: CONTESTED PARTIAL · 1 source for, 2 against · Last checked 3 Oct 2026

The private library was unavailable for some searches in this check. Missing library results are not evidence against the claim.

Rogiński, S., Brzęcka, M., Liebert, A., Krupiniewicz, K., Wojciechowcz, M., Rogiński, M., Suchcicki, M., Chojnowski, L., Mazurek, K., & Dominiczak, A. (2026). EFFECTS OF COLD-WATER IMMERSION (≤14°C) ON PHYSIOLOGICAL RECOVERY, INFLAMMATION, AND PERFORMANCE: A SYSTEMATIC REVIEW OF HUMAN STUDIES. doi.org. https://doi.org/10.31435/ijitss.1(49).2026.4693

T, C., J, B., H, B., M, N., C, M., & B, S. (2025). Effects of cold-water immersion on health and wellbeing: A systematic review and meta-analysis.. doi.org. https://doi.org/10.1371/journal.pone.0317615

Health effects of voluntary exposure to cold water – a continuing subject of debate - PMC Lock. (n.d.). pmc.ncbi.nlm.nih.gov. https://doi.org/10.1080/22423982.2022.2111789