A reader posted on facebook

” Hi Ken, have you heard anything about L. Salivarius being bad for CFS patients? I’m trying Custom Probiotics d-lactate-free formula at the moment. There’s a patient on the PhoenixRising forum who believes L. Salavirus permanently worsened their condition, and also claimed it can destroy beneficial bacteria a la antibiotics. Have you ever read anything along these lines?”

First thing is simple: L. Salivarius does kill other bacteria – the questions is whether it kills the good ones or the bad ones (or kills randomly!). The “antibiotic” that it produces is called a bacteriocin. “bacteriocins are being tested to assess their application as narrow-spectrum antibiotics.^[1]“

This may depend on the strain — unfortunately, the strain is often not put on to many commercial probiotics.

• “an up-to-date overview of all L. salivarius strains, isolated from different origins, known as bacteriocin producing and/or potential probiotic.” [2013], from the complete article:
  • … are producers of unmodified bacteriocin of subclasses IIa,IIb and IId…
  • inhibits … Bacillus, Listeria, Enterococcus and Staphylococcus
  • .. against Lactobacillys delbrueckii subsp bulgaricus (used in many yogurts)
  • .. against Enterococcus faecalis, E. faecium and Neisseria gonorrhoeae
  • .. against S. mutans, Streptococcus pneumoniae, Staphylococcus aureus, micrococcus flavus and Salmonella enteritidis
  • … against Campylobacter jejuni
  • .. active against more phylogenetically divergent Gram-positive bacteria and occasionally against Gram-negative bacteria.
  • … against L.monocytogenes…
  • Antibiotic susceptibility profiles showed that the strains of L. salivarius were sensitive to the majority of antibiotics tested..
  • … induces Interleukin (IL)-10… IL-6
    • IL-10 is low in CFS patients [2015] and “CFS/ME patients displayed significant increases in IL-10″[2011]
    • “while low levels of IL-6 suggested early ME/CFS, the reverse was true in subjects over 18 years of age ill for more than 2 years.” [2016]

Studies on CFS/IBS/FM?

• On CFS – Zero
• On fibromyalgia – Zero
• On Irritable Bowel Disease
  • Effects of Lactobacillus salivarius 433118 on intestinal inflammation, immunity status and in vitro colon function in two mouse models of inflammatory bowel disease[2008]. “the data therefore suggest that this Lactobacillus subsp. has limited potential as a prophylactic or therapeutic treatment for inflammatory bowel disease”

Bottom Line

There is no evidence that Lactobacillus salivarius is of any benefit to CFS/FM/IBS/IBD. Within the family is a wide spectrum of bacteriocins – and the lack of positive effects suggests that it does not invoke a shift that is desirable for these conditions. There is reasonable evidence that the report forwarded by a reader may be accurate/true.

I would rank lactobacillus salivarius as a “to be avoided” probiotic.