Odds Ratio Snapshots: Histamine or Mast Cell issues

Updated: Dec 3, 2025 correcting some computations errors.

This document presents the results of statistical analysis on symptoms from viable, self-annotated Biomesight microbiome samples. The methodology for data acquisition is outlined in New Standards for Microbiome Analysis?.

Tables have been refined to display only genus- and species-level taxa, the 20 most prominent entries per group, and associations achieving statistical significance (P < 0.01).

The following sections provide the processed data, accompanied by guidance on interpretation and application. Counts of significant bacterial taxa are included, reflecting the application of non-standard but rigorously validated statistical approaches to extensive sample and reference populations, where statistical power derives from dataset scale

SignificanceGenus
p < 0.01219
p < 0.001189
p < 0.0001161
p < 0.00001143

Averages and Medians

I prefer medians over averages. Medians are the values where half of the people have less and half has more. If the data was a bell-curve, then the values will almost be the same… with bacteria that happens rarely. Look at Bacteroides uniformis below, we see that the average is above and the median below.

If symptom median is higher than reference median, it means there is more of this bacteria. If lower, then less. This ignores how often the bacteria is seen (we average only over reports).

tax_nameRankSymptom AvarageReference AverageSymptom MedianReference Median
Bacteroidesgenus29.33625.73923.90529.302
Phocaeicolagenus11.84710.7619.19411.373
Phocaeicola vulgatusspecies6.7355.7193.3514.42
Bacteroides uniformisspecies3.252.6821.5242.07
Coprococcusgenus1.2061.4530.7470.552
Bacteroides caccaespecies1.1530.8490.2820.398
Pedobactergenus1.1740.9830.5480.659
Bilophilagenus0.4250.3430.2030.309
Bilophila wadsworthiaspecies0.4120.3350.1930.29
Bifidobacteriumgenus0.6530.9610.1320.055
Bacteroides rodentiumspecies0.4030.390.1790.23
Sutterella wadsworthensisspecies0.6420.660.0590.012
Hathewayagenus0.350.2720.1530.191
Hathewaya histolyticaspecies0.350.2720.1530.19
Phascolarctobacterium faeciumspecies0.1630.140.070.1
Lachnobacteriumgenus0.2330.3290.0760.047
Butyricimonasgenus0.1940.1860.1070.133
Anaerofilumgenus0.2660.2690.1050.13
Oribacteriumgenus0.1030.1330.0740.049
Anaerotruncusgenus0.2190.1840.1360.161

Bacteria Incidence – How often is it reported

The common sense belief is that if a bacteria is reported more often, then the amount should be higher. This is often not true. The microbiome is a complex thing. Look at Bacteroides uniformis below, we see that the average is above and the median below.

tax_nameRankIncidence Odds RatioChi2Symptoms %Reference %
Shewanella upeneispecies1.461335.824.4
Methanobrevibactergenus0.6110.413.822.4
Methanobrevibacter smithiispecies0.6210.113.521.9
Slackia isoflavoniconvertensspecies0.62912.720.4
Prosthecobactergenus1.6812.91710.1
Bifidobacterium cuniculispecies0.667.112.719.4
Desulfomonile tiedjeispecies1.457.820.213.9
Desulfomonilegenus1.447.620.214

More or Less often based on Symptom Median All Incidence

This is a little more complex to understand. If we compute the mid point for people with the symptom, then if the bacteria was not involved then half of the reference should be above this value and half below this value. If not, it means that the symptom tends to over or under growth.

tax_nameRankSymptom MedianOdds RatioChi2BelowAbove
Alcanivoraxgenus0.0020.2874.1365101
Isoalcanivoraxgenus0.0020.2873.235598
Isoalcanivorax indicusspecies0.0020.2873.235598
Nostoc flagelliformespecies0.0020.2768.330583
Pelagicoccus croceusspecies0.0020.3163.6366114
Psychroflexusgenus0.0020.3163.1348107
Psychroflexus gondwanensisspecies0.0020.3163.1348107
Niabella aurantiacaspecies0.0020.3562.5507177
Salidesulfovibriogenus0.0020.3359.7370121
Salidesulfovibrio brasiliensisspecies0.0020.3359.7370121
Deferribacter autotrophicusspecies0.0020.3259.2355115
Psychrobacter glacialisspecies0.0020.3859.2629238
Deferribactergenus0.0020.3358.4357117
Bacillus ferrariarumspecies0.0020.3456354119
Rickettsia marmionii Stenos et al. 2005species0.0020.3652.7374133
Segetibacter aerophilusspecies0.0020.3551.8356126
Thiorhodococcus pfennigiispecies0.0020.3651.7392143
Niabellagenus0.0020.451.4543215
Pontibacillus halophilusspecies0.0020.3750.7397147
Pontibacillusgenus0.0020.3750.6401149

More or Less often based on Reference Median All Incidence

This is like the above, but with a different line in the sand. Instead of the median of those with the condition, we use the median of the reference set.

tax_nameRankReference MedianOdds RatioChi2BelowAbove
Bilophilagenus0.30950.55154.421471184
Psychrobacter glacialisspecies0.0020.38145.8629238
Niabella aurantiacaspecies0.0020.35136.6507177
Alcanivoraxgenus0.0020.28134.4365101
Isoalcanivoraxgenus0.0020.28131.435598
Isoalcanivorax indicusspecies0.0020.28131.435598
Bilophila wadsworthiaspecies0.29050.58127.520961222
Bacteroides heparinolyticusspecies0.0030.49122921449
Niabellagenus0.0020.4119.8543215
Pelagicoccus croceusspecies0.0020.31118.5366114
Nostoc flagelliformespecies0.0020.27116.130583
Psychroflexusgenus0.0020.31114.9348107
Psychroflexus gondwanensisspecies0.0020.31114.9348107
Salidesulfovibriogenus0.0020.33112.8370121
Salidesulfovibrio brasiliensisspecies0.0020.33112.8370121
Actinopolysporagenus0.0020.4111.3501199
Chromatiumgenus0.0020.39111.3491193
Chromatium weisseispecies0.0020.39110.7490193
Bacteroidesgenus29.3020.62110.523181428
Thiorhodococcusgenus0.0020.42110551231

More or Less often based on Symptom Median High Incidence

Above we see that many of the top bacteria identified are sparse, that is not reported often. We then restrict them to those that occur above 50% or the time.

tax_nameRankSymptom Median FreqOdds RatioChi2BelowAbove
Clostridium taeniosporumspecies0.0030.61191266777
Dethiosulfovibriogenus0.0040.6812.31414958
Tetragenococcus doogicusspecies0.0030.6911.31280880
Hydrocarboniphaga daqingensisspecies0.0040.710.415251069
Mycoplasmopsisgenus0.0050.7110.217031201
Pediococcusgenus0.0040.756.61225919

More or Less often based on Reference Median High Incidence

Above we see that many of the top bacteria identified are sparse, that is not reported often. We then restrict them to those that occur above 50% or the time.

Bilophilagenus0.30950.55154.421471184
Psychrobacter glacialisspecies0.0020.38145.8629238
Niabella aurantiacaspecies0.0020.35136.6507177
Alcanivoraxgenus0.0020.28134.4365101
Isoalcanivorax indicusspecies0.0020.28131.435598
Isoalcanivoraxgenus0.0020.28131.435598
Bilophila wadsworthiaspecies0.29050.58127.520961222
Bacteroides heparinolyticusspecies0.0030.49122921449
Niabellagenus0.0020.4119.8543215
Pelagicoccus croceusspecies0.0020.31118.5366114
Nostoc flagelliformespecies0.0020.27116.130583
Psychroflexus gondwanensisspecies0.0020.31114.9348107
Psychroflexusgenus0.0020.31114.9348107
Salidesulfovibrio brasiliensisspecies0.0020.33112.8370121
Salidesulfovibriogenus0.0020.33112.8370121
Actinopolysporagenus0.0020.4111.3501199
Chromatiumgenus0.0020.39111.3491193
Chromatium weisseispecies0.0020.39110.7490193
Bacteroidesgenus29.3020.62110.523181428
Thiorhodococcusgenus0.0020.42110551231

Summary

A large number of bacterial taxa exhibit shifts with P < 0.01 in association with this condition. The subsequent challenge is determining how to modulate these taxa, since the volume of candidates exceeds what most individuals can practically consider. Moreover, for many of the taxa identified, there is no published evidence in the U.S. National Library of Medicine describing how to alter their abundance.

A deep optimization model, such as the one implemented on the Microbiome Taxa R2 site, can be used to inform probiotic selection. This model provides coverage for each identified taxon and infers which probiotics are most likely to shift their levels. Its output may then be integrated with more conventional recommendations derived from literature indexed in the U.S. National Library of Medicine where such evidence exists, with the two recommendation sets reconciled by giving priority to probiotic-based suggestions.

Development of a dedicated database based on Biomesight samples is in progress. The current model uses data contributed by PrecisionBiome, and datasets generated with differing laboratory processing pipelines cannot be safely combined, as discussed in The taxonomy nightmare before Christmas…. Once the Biomesight-specific database is complete, an option for generating (offline-only) personalized suggestions will be added to the Microbiome Prescription website.

Probiotics Suggestions

The following are based on a simplified algorithm using R2 data for Biomesight. These are tentative numbers subject to future refinements. Bacteria listed are only for probiotics detected with Biomesight tests. Probiotics include some that are available only in some countries and some that are pending approval for retail sale.

  • Good Count: Number of bacteria expected to shift in desired direction
  • Bad Count: Number of bacteria expected to shift in wrong direction
  • Impact: Estimator of impact based on Chi-2, Slope and R2 vectors
Probiotic SpeciesImpactGood CountBad Count
Faecalibacterium prausnitzii128.4372
Segatella copri79.14100
Bifidobacterium breve66.59161
Bifidobacterium longum59.74160
Bifidobacterium adolescentis44.18140
Lactobacillus helveticus37.5610531
Bifidobacterium bifidum13.45152
Akkermansia muciniphila12.691614
Bifidobacterium catenulatum12.37150
Enterococcus faecalis10.767027
Bifidobacterium animalis6.1170
Enterococcus faecium3.693818
Streptococcus thermophilus3.2480
Enterococcus durans1.81368
Clostridium butyricum1.46364
Escherichia coli1.2822
Bacillus subtilis0.74423
Limosilactobacillus vaginalis0.694219
Pediococcus acidilactici0.683242
Lactococcus lactis0.57112
Bifidobacterium pseudocatenulatum0.533411
Limosilactobacillus fermentum0.4148
Veillonella atypica0.38110
Lacticaseibacillus paracasei0.35175
Limosilactobacillus reuteri0.342611
Ligilactobacillus salivarius0.15712
Lactobacillus acidophilus0.143312
Heyndrickxia coagulans0.092813
Leuconostoc mesenteroides0.061713
Lacticaseibacillus rhamnosus0.0242
Lacticaseibacillus casei-0.0448
Lactobacillus crispatus-0.21323
Lactobacillus jensenii-0.213729
Lactiplantibacillus plantarum-0.2401
Lactiplantibacillus pentosus-0.2825
Odoribacter laneus-0.301
Parabacteroides distasonis-0.8932
Lactobacillus johnsonii-4.715526
Parabacteroides goldsteinii-8.88011
Blautia wexlerae-21.9632
Blautia hansenii-25.0623
Bacteroides uniformis-458.22014
Bacteroides thetaiotaomicron-489.69013