This is a look at Small intestinal bacterial overgrowth (SIBO) from the aspect of the microbiome. Whatever is happening in the small intestine flows out of it and impacts downstream systems. Items that modifies any microbiome abnormalities will likely impact the small intestine.

This post is a parallel to my earlier post Multiple Chemical Sensitivity (MCS) – A Cause Found?. We will not assume anything. Just let the data speak.

We have 181 samples annotated with SIBO. Ombre Labs: 57, uBiome: 57 and Biomesight: 57.

Literature Review

I found one study that does a very good job

Association between Gut Dysbiosis and the Occurrence of SIBO, LIBO, SIFO and IMO [2023] states “Bacteria characteristic of small intestinal bacterial overgrowth include Streptococcus, Staphylococcus, Bacteroides, and Lactobacillus. “

Microbiome Associations

We have two bacteria that are reported significant in at least 2 of the 3 labs:

• Bacteroides caccae (species)
• Holdemania (genus)

A total of 31 bacteria (P < 0.001) was flagged as being significant and added to our collection.

We then look at Percentile and found only Bifidobacterium adolescentis showing a significant shift.

The complete list is below. Note that almost everything is High with SIBO.

ShiftIs	tax_name	tax_rank
High	Flavobacteriia	class
High	Bacteroidia	class
High	Spongiibacteraceae	family
High	Lachnospiraceae	family
High	Bacteroidaceae	family
High	Flavobacteriaceae	family
High	Rhodocyclaceae	family
High	Anaerolinea	genus
High	Ethanoligenens	genus
High	Trabulsiella	genus
High	Bacteroides	genus
High	Hyphomicrobium	genus
High	Myroides	genus
high	Holdemania	genus
High	Pseudoflavonifractor	genus
High	Adlercreutzia	genus
High	Bacteroidales	order
High	Flavobacteriales	order
High	Oceanospirillales	order
High	Nitrosomonadales	order
High	Bifidobacterium thermophilum	species
High	Hyphomicrobium aestuarii	species
High	Anaerolinea thermolimosa	species
High	Thermodesulfovibrio thiophilus	species
High	Bacteroides sp. dnLKV9	species
High	Bacteroides sp. 35AE37	species
High	Bacteroides caccae	species
High	Adlercreutzia equolifaciens	species
High	Blautia obeum	species
High	Pseudoflavonifractor capillosus	species
Low	Bifidobacterium adolescentis	species

We have only one clear agreement with the literature: Bacteroides with a large number of species deemed significant.

Compounds Produced

SIBO is usually detected by breath tests. The question is whether the chemicals detected in the breath is associated with the compounds that bacteria produced. What we found is below. The top 4 product in this list are the likely suspect for the first stage. These likely contributed to the chemicals detected. In particular, N-Acyl-L-homoserine abundance is associated with “Over 50 Gram-negative bacteria species (including several pathogenic species) use AHLs as autoinducers and the means of their communication in Quorum sensing” In other words it is not the source, but sends signals to the source bacteria to release the chemicals detected on the breath.

Trying to “find” the specific bacteria is not practical

• 📚4543 different bacteria produces Hydrogen (just click to see the list)
• 📚3817 different bacteria produces Hydrogen Sulfide
• 📚622 different bacteria produces Methane.

CompoundName	percentile	Obs
Methylaminoacrylate C20255 – has NH2 and Hydrogen	61.5	129
Aminoacrylate C20253 – has NH2 and Hydrogen	61.5	129
D-Erythritol 1-phosphate C21294	60.7	134
N-Acyl-L-homoserine C18061 – a signaling molecule	60.3	126
2-O-[6-O-Octanoyl-alpha-D-glucopyranosyl-(1->6)-alpha-D-glucopyranosyl]-D-glycerate	39.8	44
(2R,3R)-Dihydroflavonol	38.6	67
6-Phospho-2-dehydro-D-gluconate	36.9	41
p-Hydroxybenzyl alcohol	34.8	56
4-Hydroxybenzaldehyde	34.8	56

Bottom Line

I have made the bacteria found above available on the site under Research tab

The page resulting looks like this:

With results like shown below. Note that on the Add with have gluten-free and on the Remove: wheat, barley.