Editing Probiotic (section)

=== Immune function and infections ===
Some strains of LAB may affect [[pathogens]] by means of [[competitive inhibition]] (i.e., by competing for growth) and some evidence suggests they may improve immune function by increasing the number of [[IgA]]-producing plasma cells and increasing or improving [[phagocytosis]], as well as increasing the proportion of [[T lymphocytes]] and natural killer cells.<ref name="Reid_Jass_Sebulsky">{{Cite journal |vauthors=Reid G, Jass J, Sebulsky MT, McCormick JK |date=October 2003 |title=Potential uses of probiotics in clinical practice |journal=Clin. Microbiol. Rev. |volume=16 |issue=4 |pages=658–672 |doi=10.1128/CMR.16.4.658-672.2003 |pmc=207122 |pmid=14557292}}</ref><ref name="Ouwehand_Salminen_Isolauri">{{Cite journal |vauthors=Ouwehand AC, Salminen S, Isolauri E |date=August 2002 |title=Probiotics: an overview of beneficial effects |url=https://link.springer.com/article/10.1023/A:1020620607611 |journal=Antonie van Leeuwenhoek |volume=82 |issue=1–4 |pages=279–289 |doi=10.1023/A:1020620607611 |pmid=12369194 |access-date=2022-12-01 |url-access=subscription |s2cid=1870018 |archive-date=2022-12-02 |archive-url=https://web.archive.org/web/20221202022802/https://link.springer.com/article/10.1023/A:1020620607611 |url-status=live }}</ref> LAB products might aid in the treatment of acute diarrhea and possibly affect [[rotavirus]] infections in children and travelers' diarrhea in adults,<ref name="Reid_Jass_Sebulsky" /><ref name="Ouwehand_Salminen_Isolauri" /> but no products are approved for such indications. There are weak evidence probiotics might lower the incidence of acute upper respiratory tract infections in adults, they were better than placebo or no treatment.<ref>{{Cite journal |last1=Zhao |first1=Yunli |last2=Dong |first2=Bi Rong |last3=Hao |first3=Qiukui |date=2022-08-24 |title=Probiotics for preventing acute upper respiratory tract infections |journal=The Cochrane Database of Systematic Reviews |volume=2022 |issue=8 |pages=CD006895 |doi=10.1002/14651858.CD006895.pub4 |issn=1469-493X |pmc=9400717 |pmid=36001877}}</ref>

Probiotics do not appear to change the risk of infection in older people.<ref>{{Cite journal |last1=Wachholz |first1=PA |last2=Nunes |first2=VDS |last3=Polachini do Valle |first3=A |last4=Jacinto |first4=AF |last5=Villas-Boas |first5=PJF |date=3 February 2018 |title=Effectiveness of probiotics on the occurrence of infections in older people: systematic review and meta-analysis. |journal=Age and Ageing |volume=47 |issue=4 |pages=527–536 |doi=10.1093/ageing/afy006 |pmid=29415116 |doi-access=free |hdl=11449/164454|hdl-access=free }}</ref>