Odds Ratio Snapshot: Depression

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 < 0.01196
p < 0.001172
p < 0.0001154
p < 0.00001140

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 Bifidobacterium 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
Bacteroidesgenus28.80225.92624.22427.059
Phocaeicolagenus12.35710.7869.31411.306
Phocaeicola vulgatusspecies7.0435.7513.3944.929
Bacteroides uniformisspecies2.9092.7231.5531.958
Bacteroides thetaiotaomicronspecies1.2341.0650.4580.734
Coprococcusgenus1.231.440.7370.552
Roseburia faecisspecies0.9691.2170.5770.455
Bilophilagenus0.4170.3470.2070.319
Bifidobacteriumgenus0.5340.9530.1310.035
Bacteroides stercorisspecies2.0661.5430.0330.123
Blautia coccoidesspecies0.7760.9170.5920.504
Bilophila wadsworthiaspecies0.3950.3390.1970.281
Mediterraneibactergenus0.8850.7080.2780.326
Butyricimonasgenus0.2170.1860.1080.154
Hathewayagenus0.3140.2770.1550.201
Hathewaya histolyticaspecies0.3140.2770.1550.201
Bacteroides rodentiumspecies0.4350.390.1860.231
Bifidobacterium longumspecies0.2370.3260.0510.012
Lachnobacteriumgenus0.1970.3270.0750.041
Bacteroides stercorirosorisspecies0.2340.1910.1350.164

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 %
Bifidobacterium brevespecies0.647.826.641.4
Anaerococcus hydrogenalisspecies1.667.218.211

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
Niabella aurantiacaspecies0.0020.3444.3544183
Psychroflexusgenus0.0020.3143.7357111
Psychroflexus gondwanensisspecies0.0020.3143.7357111
Rickettsia marmionii Stenos et al. 2005species0.0020.3341.6398131
Psychrobacter glacialisspecies0.0020.3738.6660246
Niabellagenus0.0020.3836584222
Chromatiumgenus0.0020.3834.4517198
Chromatium weisseispecies0.0020.3834.2516198
Lentibacillusgenus0.0020.3834510196
Lentibacillus salinarumspecies0.0020.3833.7494190
Viridibacillus neideispecies0.0020.3833.3469180
Thermoanaerobacteriumgenus0.0020.4130483196
Thiomicrospiragenus0.0020.3929.3335130
Sporosarcina pasteuriispecies0.0020.4129.2439178
Thiorhodococcusgenus0.0020.4229.1578243
Thermoanaerobacterium islandicumspecies0.0020.4129476196
Syntrophomonas sapovoransspecies0.0020.4229534223
Sporosarcinagenus0.0020.4227.5443185
Thermodesulfovibrio thiophilusspecies0.0020.4425.5536237
Oenococcusgenus0.0020.4524.8604273

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
Bifidobacterium longumspecies0.0122.27260.28701971
Bifidobacteriumgenus0.0352.04241.712662586
Methylobacillus glycogenesspecies0.0030.4232.51250497
Methylobacillusgenus0.0030.41217.21249516
Corynebacteriumgenus0.00850.42201.91163486
Bilophilagenus0.31850.55162.822471236
Erysipelothrix murisspecies0.0150.5516121531179
Psychrobacter glacialisspecies0.0020.37156.5660246
Niabella aurantiacaspecies0.0020.34153.5544183
Methylonatrumgenus0.0040.53145.21620866
Methylonatrum kenyensespecies0.0040.53145.21620866
Catonella morbispecies0.010.5614419681099
Catonellagenus0.010.56141.419661104
Erysipelothrixgenus0.01550.57139.921511232
Niabellagenus0.0020.38137584222
Megasphaera elsdeniispecies0.00450.41132.7640260
Bacteroides thetaiotaomicronspecies0.7340.6130.123891422
Veillonella parvulaspecies0.0031.9128.66661266
Alkalithermobacter paradoxusspecies0.0040.55125.81537853
Odoribacter denticanisspecies0.0050.57124.11642928

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 taeniosporumspecies0.0030.6111.21344814
Dethiosulfovibriogenus0.0040.667.61500994
Tetragenococcus doogicusspecies0.0030.677.21360910

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.

tax_nameRankReference Median FreqOdds RatioChi2BelowAbove
Bifidobacterium longumspecies0.0122.27260.28701971
Bifidobacteriumgenus0.0352.04241.712662586
Methylobacillus glycogenesspecies0.0030.4232.51250497
Methylobacillusgenus0.0030.41217.21249516
Corynebacteriumgenus0.00850.42201.91163486
Bilophilagenus0.31850.55162.822471236
Erysipelothrix murisspecies0.0150.5516121531179
Psychrobacter glacialisspecies0.0020.37156.5660246
Niabella aurantiacaspecies0.0020.34153.5544183
Methylonatrumgenus0.0040.53145.21620866
Methylonatrum kenyensespecies0.0040.53145.21620866
Catonella morbispecies0.010.5614419681099
Catonellagenus0.010.56141.419661104
Erysipelothrixgenus0.01550.57139.921511232
Niabellagenus0.0020.38137584222
Megasphaera elsdeniispecies0.00450.41132.7640260
Bacteroides thetaiotaomicronspecies0.7340.6130.123891422
Veillonella parvulaspecies0.0031.9128.66661266
Alkalithermobacter paradoxusspecies0.0040.55125.81537853
Odoribacter denticanisspecies0.0050.57124.11642928

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

Some literature suggesting that the model’s suggestions are reasonable:

  • Bifidobacterium breve Bif11 supplementation improves depression-related neurobehavioural and neuroinflammatory changes in the mouse. Neuropharmacology (Neuropharmacology ) Vol: 229 Issue: Pages: 109480 Pub: 2023 May 15 ePub: 2023 Mar 1 Authors Sushma G,Vaidya B,Sharma S,Devabattula G,Bishnoi M,Kondepudi KK,Sharma SS
  • Heat-sterilized Bifidobacterium breve prevents depression-like behavior and interleukin-1ß expression in mice exposed to chronic social defeat stress. Brain, behavior, and immunity (Brain Behav Immun ) Vol: Issue: Pages: Pub: 2021 May 29 ePub: 2021 May 29 Authors Kosuge A,Kunisawa K,Arai S,Sugawara Y,Shinohara K,Iida T,Wulaer B,Kawai T,Fujigaki H,Yamamoto Y,Saito K,Nabeshima T,Mouri A
  • Bifidobacterium breve BB05 alleviates depressive symptoms in mice via the AKT/mTOR pathway.
    Frontiers in nutrition (Front Nutr ) Vol: 12 Issue: Pages: 1529566 Pub: 2025 ePub: 2025 Jan 30 Authors Pan Y,Huang Q,Liang Y,Xie Y,Tan F,Long X
  • Lipid and Energy Metabolism of the Gut Microbiota Is Associated with the Response to Probiotic Bifidobacterium breve Strain for Anxiety and Depressive Symptoms in Schizophrenia.
    Journal of personalized medicine (J Pers Med ) Vol: 11 Issue: 10 Pages: Pub: 2021 Sep 30 ePub: 2021 Sep 30 Authors Yamamura R,Okubo R,Katsumata N,Odamaki T,Hashimoto N,Kusumi I,Xiao J,Matsuoka YJ
  • Towards a psychobiotic therapy for depression: Bifidobacterium breve CCFM1025 reverses chronic stress-induced depressive symptoms and gut microbial abnormalities in mice. Neurobiology of stress (Neurobiol Stress ) Vol: 12 Issue: Pages: 100216 Pub: 2020 May ePub: 2020 Mar 20 Authors Tian P,O’Riordan KJ,Lee YK,Wang G,Zhao J,Zhang H,Cryan JF,Chen W
Probiotic SpeciesImpactGood CountBad Count
Faecalibacterium prausnitzii256.6280
Blautia hansenii181.61221
Bifidobacterium breve89.17150
Bifidobacterium longum79.15152
Blautia wexlerae59.8870
Bifidobacterium adolescentis58.57142
Segatella copri41.7930
Bifidobacterium bifidum17.98112
Bifidobacterium catenulatum15.5780
Escherichia coli14.66110
Enterococcus faecalis14.274246
Akkermansia muciniphila11.57129
Lactobacillus helveticus9.864353
Bifidobacterium animalis8.1770
Enterococcus faecium5.051434
Streptococcus thermophilus2.340
Enterococcus durans2.142523
Veillonella atypica1.34120
Clostridium butyricum0.671326
Bacillus subtilis0.512833
Lacticaseibacillus paracasei0.23135
Lactococcus lactis0.1525
Limosilactobacillus fermentum0.121017
Lactiplantibacillus pentosus0.164
Heyndrickxia coagulans0.04814
Ligilactobacillus salivarius-0.05210
Lactiplantibacillus plantarum-0.0836
Lacticaseibacillus casei-0.17110
Lacticaseibacillus rhamnosus-0.1825
Limosilactobacillus vaginalis-0.222551
Leuconostoc mesenteroides-0.26413
Bifidobacterium pseudocatenulatum-0.35724
Lactobacillus crispatus-0.63231
Limosilactobacillus reuteri-0.781722
Lactobacillus acidophilus-0.83533
Odoribacter laneus-1.7803
Lactobacillus jensenii-3.231855
Pediococcus acidilactici-7.222633
Lactobacillus johnsonii-13.523639
Parabacteroides goldsteinii-21.27013
Parabacteroides distasonis-27.34011
Bacteroides uniformis-285.55011
Bacteroides thetaiotaomicron-294.72010

Odds Ratio Snapshots: Unrefreshed sleep

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 < 0.01149
p < 0.001121
p < 0.000196
p < 0.0000179

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
Bacteroidesgenus28.50425.67423.87227.629
Bacteroides uniformisspecies3.0782.6781.511.977
Coprococcusgenus1.2581.4580.750.539
Bifidobacteriumgenus0.6770.9740.1350.064
Bacteroides cellulosilyticusspecies1.060.8220.0730.126
Bilophilagenus0.3970.3430.2060.252
Bilophila wadsworthiaspecies0.3850.3350.1960.239
Alkaliphilusgenus0.2510.2990.070.041
Alkaliphilus crotonatoxidansspecies0.2450.2910.0650.037
Collinsellagenus0.1460.1880.0580.036
Bifidobacterium longumspecies0.2210.3380.0520.03
Bacteroides stercorirosorisspecies0.2160.190.1340.156
Collinsella aerofaciensspecies0.1380.1750.0560.036
Caloramator mitchellensisspecies0.7980.8730.0540.035
Anaerotruncusgenus0.1950.1860.1360.155
Bacteroides salyersiaespecies0.2620.3670.0220.004
Bacteroides faecisspecies0.1450.1180.0550.071
Anaerotruncus colihominisspecies0.1840.1740.1330.147
Oxalobactergenus0.0360.030.0180.027
Luteibacter anthropispecies0.0510.080.0160.009

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 %
Bifidobacterium scardoviispecies0.716.612.317.2

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
Niabella aurantiacaspecies0.0020.3479.6484165
Psychrobacter glacialisspecies0.0020.3778.5594218
Niabellagenus0.0020.3966516201
Viridibacillus neideispecies0.0020.3861.6426163
Actinopolysporagenus0.0020.461.5489195
Chromatiumgenus0.0020.461.4473187
Chromatium weisseispecies0.0020.461.1472187
Lentibacillusgenus0.0020.458.9459184
Lentibacillus salinarumspecies0.0020.4156.7444180
Thermoanaerobacteriumgenus0.0020.4253.1438183
Thiorhodococcusgenus0.0020.4453.1524229
Thermoanaerobacterium islandicumspecies0.0020.4251.3432183
Syntrophomonas sapovoransspecies0.0020.4450.8482211
Thermodesulfovibrio thiophilusspecies0.0020.4449.5481213
Thermodesulfovibriogenus0.0020.4746.8552258
Desulfofundulusgenus0.0020.4546.7449201
Helicobacter suncusspecies0.0020.4946.3669325
Oenococcusgenus0.0020.4745.1529249
Vagococcus penaeispecies0.0030.4936.1427211
Viridibacillusgenus0.0020.534.8437220

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
Psychrobacter glacialisspecies0.0020.37144.3594218
Niabella aurantiacaspecies0.0020.34134.5484165
Niabellagenus0.0020.39116.9516201
Bacteroides heparinolyticusspecies0.0030.49111.1858423
Actinopolysporagenus0.0020.4107.5489195
Chromatiumgenus0.0020.4106473187
Chromatium weisseispecies0.0020.4105.4472187
Viridibacillus neideispecies0.0020.38102426163
Lentibacillusgenus0.0020.4100.9459184
Thiorhodococcusgenus0.0020.4496.8524229
Lentibacillus salinarumspecies0.0020.4196.2444180
Helicobacter suncusspecies0.0020.4994.8669325
Thermoanaerobacteriumgenus0.0020.4290.2438183
Syntrophomonas sapovoransspecies0.0020.4489.9482211
Thermodesulfovibriogenus0.0020.4788.2552258
Thermodesulfovibrio thiophilusspecies0.0020.4487.8481213
Thermoanaerobacterium islandicumspecies0.0020.4287432183
Oenococcusgenus0.0020.4783.9529249
Hydrogenophilusgenus0.0030.5881.21019589
Desulfofundulusgenus0.0020.4581449201

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 taeniosporumspecies0.0030.6224.81203751
Dethiosulfovibriogenus0.0040.6817.51353917
Tetragenococcus doogicusspecies0.0030.6915.81214836
Hydrocarboniphaga daqingensisspecies0.0040.7113.814531032
Mycoplasmopsisgenus0.0050.7213.316001147
Pediococcusgenus0.0040.768.71168886
Propionisporagenus0.0050.777.913741060
Propionispora hippeispecies0.0050.777.913741060
Tetragenococcusgenus0.0030.786.71186931

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.

tax_nameRankReference Median FreqOdds RatioChi2BelowAbove
Psychrobacter glacialisspecies0.0020.37144.3594218
Niabella aurantiacaspecies0.0020.34134.5484165
Niabellagenus0.0020.39116.9516201
Bacteroides heparinolyticusspecies0.0030.49111.1858423
Actinopolysporagenus0.0020.4107.5489195
Chromatiumgenus0.0020.4106473187
Chromatium weisseispecies0.0020.4105.4472187
Viridibacillus neideispecies0.0020.38102426163
Lentibacillusgenus0.0020.4100.9459184
Thiorhodococcusgenus0.0020.4496.8524229
Lentibacillus salinarumspecies0.0020.4196.2444180
Helicobacter suncusspecies0.0020.4994.8669325
Thermoanaerobacteriumgenus0.0020.4290.2438183
Syntrophomonas sapovoransspecies0.0020.4489.9482211
Thermodesulfovibriogenus0.0020.4788.2552258
Thermodesulfovibrio thiophilusspecies0.0020.4487.8481213
Thermoanaerobacterium islandicumspecies0.0020.4287432183
Oenococcusgenus0.0020.4783.9529249
Hydrogenophilusgenus0.0030.5881.21019589
Desulfofundulusgenus0.0020.4581449201

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
Bifidobacterium breve53.54160
Blautia hansenii52.64120
Bifidobacterium longum48.23190
Segatella copri45.2350
Bifidobacterium adolescentis35.47150
Lactobacillus helveticus20.587511
Akkermansia muciniphila18.74161
Faecalibacterium prausnitzii15.5930
Bifidobacterium bifidum10.9160
Bifidobacterium catenulatum10.1150
Enterococcus faecalis9.155510
Escherichia coli6.2980
Bifidobacterium animalis4.9270
Lactobacillus johnsonii3.79515
Enterococcus faecium3.77283
Enterococcus durans3.18391
Streptococcus thermophilus1.6430
Blautia wexlerae1.5610
Limosilactobacillus vaginalis1.06346
Lactobacillus jensenii0.854110
Limosilactobacillus reuteri0.52236
Clostridium butyricum0.49193
Bifidobacterium pseudocatenulatum0.37230
Bacillus amyloliquefaciens group0.314411
Lacticaseibacillus paracasei0.31101
Lactobacillus acidophilus0.27241
Veillonella atypica0.2760
Heyndrickxia coagulans0.26202
Lactobacillus crispatus0.24172
Ligilactobacillus salivarius0.1690
Lacticaseibacillus casei0.1472
Lactiplantibacillus pentosus0.1450
Bacillus subtilis group0.13224
Limosilactobacillus fermentum0.12135
Lactococcus lactis0.1250
Leuconostoc mesenteroides0.11141
Lactiplantibacillus plantarum0.141
Lacticaseibacillus rhamnosus0.0940
Pediococcus0.0740
Bacillus0.0720
Bacillus subtilis-0.323112
Pediococcus acidilactici-2.332812
Parabacteroides goldsteinii-13.7408
Parabacteroides distasonis-27.708
Bacteroides uniformis-246.88013
Bacteroides thetaiotaomicron-265.51014

Odds Ratio Snapshots: Neurocognitive: Brain Fog

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 < 0.01135
p < 0.001100
p < 0.000183
p < 0.0000169

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
Bacteroidesgenus27.30325.83524.00826.554
Bacteroides uniformisspecies3.0262.681.4982.016
Phocaeicola doreispecies3.352.830.3790.672
Coprococcusgenus1.3541.4440.7390.612
Bifidobacteriumgenus0.6980.9750.1360.064
Bacteroides cellulosilyticusspecies0.8830.8490.070.138
Bilophilagenus0.410.340.2060.25
Bacteroides rodentiumspecies0.4160.3870.1790.221
Bilophila wadsworthiaspecies0.40.3310.1970.235
Bifidobacterium longumspecies0.2440.3360.0520.03
Anaerotruncusgenus0.1970.1850.1360.156
Anaerotruncus colihominisspecies0.1870.1730.1320.15
Collinsellagenus0.1460.1890.0570.042
Collinsella aerofaciensspecies0.1390.1760.0540.042
Anaerobranca zavarziniispecies0.140.1590.0150.009
Anaerobrancagenus0.140.1590.0150.009
Bifidobacterium adolescentisspecies0.2810.3050.0130.007
Oxalobactergenus0.0330.030.0180.023
Bifidobacterium choerinumspecies0.0370.0520.0120.007
Acholeplasma hippikonspecies0.0510.0420.0060.01

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 %
Aggregatibactergenus0.757.418.524.7
Prevotella biviaspecies1.296.624.419
Bifidobacterium scardoviispecies0.717.112.417.3

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
Psychrobacter glacialisspecies0.0020.3781584215
Chromatiumgenus0.0020.3869.5466175
Chromatium weisseispecies0.0020.3869.2465175
Niabellagenus0.0020.465.2500199
Actinopolysporagenus0.0020.464.4482191
Thiorhodococcusgenus0.0020.4357.4516221
Syntrophomonas sapovoransspecies0.0020.4355.9477203
Thermodesulfovibrio thiophilusspecies0.0020.4452.9480210
Thermodesulfovibriogenus0.0020.4650.9554255
Oenococcusgenus0.0020.4650.7528241
Helicobacter suncusspecies0.0020.4946.3656324
Desulfofundulusgenus0.0020.4741.9434206
Caldithrixgenus0.0020.5236.7541282
Desulfotomaculum defluviispecies0.0030.5636.2906508
Viridibacillusgenus0.0020.5233.7430222
Streptococcus infantisspecies0.0030.5633.2707396
Sporotomaculum syntrophicumspecies0.0030.5832.4996582
Alkalibacteriumgenus0.0030.5831.6792456
Hydrogenophilusgenus0.0030.5931.6994585
Pelagicoccusgenus0.0020.5830.7750433

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
Psychrobacter glacialisspecies0.0020.37141.3584215
Bacteroides heparinolyticusspecies0.0030.49114849412
Chromatiumgenus0.0020.38113.2466175
Chromatium weisseispecies0.0020.38112.6465175
Odoribacter denticanisspecies0.0050.56110.51455822
Niabellagenus0.0020.4109.6500199
Actinopolysporagenus0.0020.4107482191
Thiorhodococcusgenus0.0020.4399516221
Syntrophomonas sapovoransspecies0.0020.4393.7477203
Thermodesulfovibriogenus0.0020.4691.2554255
Helicobacter suncusspecies0.0020.4989.5656324
Thermodesulfovibrio thiophilusspecies0.0020.4489.5480210
Oenococcusgenus0.0020.4689.2528241
Desulfotomaculum defluviispecies0.0030.5681.7906508
Sporotomaculum syntrophicumspecies0.0030.5876.8996582
Hydrogenophilusgenus0.0030.5974.9994585
Desulfosporosinusgenus0.00251.6771.56001004
Clostridium taeniosporumspecies0.0030.6270.11184734
Desulfofundulusgenus0.0020.4769.5434206
Alkalibacteriumgenus0.0030.5868.1792456

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 taeniosporumspecies0.0030.6227.21184734
Mycoplasmopsis edwardiispecies0.0050.6721.115801053
Dethiosulfovibriogenus0.0040.67201335893
Tetragenococcus doogicusspecies0.0030.6718.81206813
Hydrocarboniphaga daqingensisspecies0.0040.7213.814221022
Mycoplasmopsisgenus0.0050.741215501142
Pediococcusgenus0.0040.75101141855
Tetragenococcusgenus0.0030.769.21183899
Propionispora hippeispecies0.0050.778.513481039
Propionisporagenus0.0050.778.513481039
Phocaeicola coprocolaspecies0.0040.787.21068836
Porphyromonas canisspecies0.0050.86.613821100

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.

tax_nameRankReference Median FreqOdds RatioChi2BelowAbove
Psychrobacter glacialisspecies0.0020.37141.3584215
Bacteroides heparinolyticusspecies0.0030.49114849412
Chromatiumgenus0.0020.38113.2466175
Chromatium weisseispecies0.0020.38112.6465175
Odoribacter denticanisspecies0.0050.56110.51455822
Niabellagenus0.0020.4109.6500199
Actinopolysporagenus0.0020.4107482191
Thiorhodococcusgenus0.0020.4399516221
Syntrophomonas sapovoransspecies0.0020.4393.7477203
Thermodesulfovibriogenus0.0020.4691.2554255
Helicobacter suncusspecies0.0020.4989.5656324
Thermodesulfovibrio thiophilusspecies0.0020.4489.5480210
Oenococcusgenus0.0020.4689.2528241
Desulfotomaculum defluviispecies0.0030.5681.7906508
Sporotomaculum syntrophicumspecies0.0030.5876.8996582
Hydrogenophilusgenus0.0030.5974.9994585
Desulfosporosinusgenus0.00251.6771.56001004
Clostridium taeniosporumspecies0.0030.6270.11184734
Desulfofundulusgenus0.0020.4769.5434206
Alkalibacteriumgenus0.0030.5868.1792456

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
Segatella copri11.2410
Lactobacillus helveticus10.1722
Bifidobacterium breve6.1710
Bifidobacterium longum5.9810
Bifidobacterium adolescentis4.6710
Bifidobacterium bifidum1.6710
Bifidobacterium catenulatum1.0410
Blautia wexlerae0.7110
Bifidobacterium animalis0.710
Enterococcus faecalis0.1723
Limosilactobacillus reuteri0.1430
Enterococcus durans0.1151
Lactobacillus johnsonii0.1130
Lactococcus lactis0.0910
Limosilactobacillus vaginalis0.0331
Bifidobacterium pseudocatenulatum0.0221
Escherichia coli0.0210
Lacticaseibacillus rhamnosus0.0210
Enterococcus faecium0.0111
Akkermansia muciniphila-0.0101
Ligilactobacillus salivarius-0.0101
Bacillus subtilis-0.0243
Lactobacillus jensenii-0.0222
Lactobacillus crispatus-0.0313
Pediococcus acidilactici-1.0923
Bacteroides uniformis-32.2601
Bacteroides thetaiotaomicron-33.3501

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

Odds Ratios for Neurological-Audio: hypersensitivity to noise

I just got an email asking for which bacteria are involved with hypersensitivity to noise. This post is just presenting the tables derived from the methodology described in this technical post: Odds Ratios and the Microbiome

Here are some odds ratios using BiomeSight data. Odds Low means when the reading is below the Median and Odds High above the Median (of those with this symptom). We use the symptom median to get balanced (same approximate size) categories. Using an average results in poorer results.

A 1.2 in Odds Low, means that having less then typical/median increases your odds, i.e. you want to increase the amount.

At first look for probiotics, we see:

  • Bifidobacterium adolescentis
  • Bifidobacterium longum
  • Lactococcus

I also note that Odds Low really dominant, i.e. too little of a lot of different bacteria. This hints at Prescript-Assist®/SBO Probiotic with 22 different unusual probiotics as being a possible candidate as well as General Biotics/Equilibrium.

Tax_Nametax_RankOdds LowOdd High
Collinsella tanakaeispecies0.741.67
Segatella paludivivensspecies1.560.73
Viridiplantaekingdom1.510.65
Peptostreptococcus stomatisspecies1.470.69
Bacteroides salyersiaespecies1.420.74
Neisserialesorder1.420.63
Bifidobacteriumgenus1.420.77
Bifidobacterium adolescentisspecies1.410.76
Bifidobacterialesorder1.410.77
Bifidobacteriaceaefamily1.410.77
genistoids sensu latoclade1.400.72
rosidsclade1.400.72
Rothiagenus1.400.72
core genistoidsclade1.400.72
Crotalarieaetribe1.400.72
Fabaceaefamily1.400.72
Papilionoideaesubfamily1.400.72
50 kb inversion cladeclade1.400.72
Fabalesorder1.400.72
fabidsclade1.400.72
Desulfosporosinusgenus1.390.76
Gunneridaeclade1.390.73
Streptophytinasubphylum1.390.73
Tracheophytaclade1.390.73
Embryophytaclade1.390.73
eudicotyledonsclade1.390.73
Spermatophytaclade1.390.73
Magnoliopsidaclass1.390.73
Mesangiospermaeclade1.390.73
Euphyllophytaclade1.390.73
Streptophytaphylum1.390.73
Pentapetalaeclade1.390.73
Bifidobacterium choerinumspecies1.380.77
Neisseriagenus1.380.67
Bifidobacterium adolescentis JCM 15918strain1.370.79
Lysobactergenus0.791.37
Neisseriaceaefamily1.370.65
Rothiagenus1.360.75
Actinomycetotaphylum1.360.79
Bifidobacterium gallicumspecies1.350.75
Catenibacterium mitsuokaispecies1.350.72
Planococcusgenus1.340.57
Bifidobacterium indicumspecies1.340.75
Planococcus columbaespecies1.340.58
Enterobactergenus1.340.80
Morganellaceaefamily1.330.64
Clostridium chartatabidumspecies1.330.78
Sutterella stercoricanisspecies1.320.78
Aeromonadalesorder1.320.75
Mesoplasma entomophilumspecies1.310.78
Rothia mucilaginosaspecies1.300.78
Entomoplasmataceaefamily1.300.79
Entomoplasmatalesorder1.300.79
Eukaryotasuperkingdom1.300.71
Mesoplasmagenus1.300.79
Succinivibriogenus1.300.76
Bifidobacterium longumspecies1.290.81
Succinivibrionaceaefamily1.290.81
Ruminococcus callidusspecies1.290.78
Streptococcus cristatusspecies1.280.58
Tepidibactergenus1.280.82
Catenibacteriumgenus1.280.76
Atopobium fossorspecies1.280.62
Rivulariaceaefamily1.270.82
Dyadobactergenus1.270.63
Actinomycetesclass1.270.82
Oribacteriumgenus1.270.82
Clostridium cadaverisspecies1.260.83
Micrococcaceaefamily1.260.72
Micromonosporaceaefamily1.260.65
Micromonosporalesorder1.260.65
Streptococcus sanguinisspecies1.250.73
Citrobactergenus1.250.83
Oribacterium sinusspecies1.250.83
Acinetobactergenus1.250.75
Salisaetaceaefamily1.250.59
Salisaetagenus1.250.59
Salisaeta longaspecies1.240.59
Thermosediminibacteralesorder1.230.83
Candidatus Tammella caduceiaespecies1.230.76
Lachnobacteriumgenus1.230.84
Alishewanellagenus1.230.62
Heliorestisgenus1.230.84
Actinocatenisporagenus1.220.65
Azospirillumgenus1.220.80
Candidatus Tammellagenus1.220.77
Bifidobacterium catenulatum PV20-2strain1.220.84
Lactococcusgenus1.220.83
Bifidobacterium subtilespecies1.220.84
Negativicoccusgenus1.220.82
Succinivibrio dextrinosolvensspecies1.210.85
Opisthokontaclade1.210.71
Eumetazoaclade1.210.71
Metazoakingdom1.210.71
Caloramator indicusspecies1.210.85
Desulfurisporaceaefamily1.210.78
Desulfurisporagenus1.210.78
Desulfurispirillum alkaliphilumspecies1.210.81
Streptococcus millerispecies1.210.79
Coprococcus eutactusspecies1.210.84
Desulfurispora thermophilaspecies1.210.78
Herbaspirillum magnetovibriospecies1.200.59
Phocaeicola massiliensisspecies1.200.85
Prevotella dentasinispecies1.200.79
Collinsella intestinalisspecies1.200.81
Pseudomonasgenus1.200.85
Coraliomargarita akajimensisspecies1.200.67
Coraliomargaritaceaefamily1.200.67
Coraliomargaritagenus1.200.67
Pseudomonadaceaefamily1.200.85
Bilateriaclade1.200.72

Odds Ratios and the Microbiome

In working with Microbiome Prescription, I experimented with various prediction approaches before settling on a workaround that, in many cases, could successfully predict the top 10 symptoms for new microbiome samples, with individuals confirming about 80% of them as accurate reflections of their own symptoms. Though this solution was adequate for practical needs, it was admittedly less than ideal in theory. Recently, I recognized that a more robust and principled prediction algorithm is achievable. The aim of this post is to walk through that process, making it accessible for anyone interested in trying this more rigorous approach.

Accurate prediction identifies the key bacteria that should be altered with statistical justification.

An odds ratio (OR) is a measure of association that describes the odds of a disease, symptom, or event occurring in one group compared to another, often used in medical and epidemiological studies to estimate the strength of risk factors or the effectiveness of interventions.

Understanding Odds Ratios

  • The odds ratio is calculated by dividing the odds of the event in the exposed group by the odds in the non-exposed group.
  • OR > 1 indicates higher odds of disease with the exposure or risk factor; OR < 1 indicates reduced odds; OR = 1 means no difference in odds between groups.
  • Odds ratios are especially used in case-control studies, but also in cohort and cross-sectional studies, and they can approximate risk ratios when the disease or symptom is rare.

Using Multiple Odds Ratios in Disease Analysis

When you have several odds ratios related to a disease, there are several key uses:

  • Compare the magnitude of different risk factors: By looking at the odds ratios for various exposures (e.g., smoking, age group, genetic markers), you can identify which exposures are most strongly associated with the disease.​​
  • Synthesize evidence: Meta-analysis allows combining odds ratios from multiple studies to produce a summary effect estimate, which helps determine overall strength of association and consistency across populations.

Example Table of Interpreting Odds Ratios

Exposure/Risk FactorOdds RatioInterpretation
Smoking3.5 Exposure increases odds
Physical Activity0.7 Exposure decreases odds
High BMI1.2 Exposure slightly increases odds
Family History4.0 Strong increased odds

These odds ratios can guide targeted interventions, identify priority risk factors, and inform clinical decision-making or public health policy.

Each odds ratio’s confidence interval should be considered to determine statistical significance: if it includes 1, the specific association may not be statistically meaningful.

Summary

The charts below used naïve odds ratio computation (ignoring Probability) of people with declared symptom and those without this symptoms. If you use Zero(0) as a threshold, we correctly predicted 74% of the time for those with symptoms and those without symptoms.

Odds ratios quantify the likelihood of disease or symptoms given exposures and allow comparison and synthesis of risk across different factors or populations. When handling multiple odds ratios, use them to identify, adjust for, and summarize the impact of risk factors on disease occurrence.

Applying to the Microbiome

We encounter some challenges here. Consider this constructed example:

  • Bacteria Foo has OR of 1.5 when the microbiome exceeds 5%
  • Bacteria Bar has OR of 2 when the microbiome exceeds 3%
  • Bacteria Foo and Bar are associated.

If a sample has both, the OR is not 1.5 x 2 or 3.0. Instead, we need to know much they influence each other, i.e. the R2. We can estimate this from Microbiome Taxa R2 Site. Suppose that R2 is 0.5, significant inference.

The Odds ratio is thus reduced to 2.66 from 3.0.

Odds Ratios and Continuous Values

Odds ratios are commonly used for binary data, such as smoker versus non-smoker or high school graduation status. Continuous data can also be categorized; for example, instead of treating smoking as simply yes/no, you might use metrics like the number of cigarettes smoked per day or packs per week. Similarly, the microbiome data can be categorized, though caution is needed to avoid over-interpreting sparse data. A rough guideline from many studies suggests a minimum of 30 cases and 30 controls are needed to calculate an odds ratio with basic reliability. For data on the lower end, it can be helpful to binarize using the median rather than the mean. This is important because bacterial abundances tend to be highly skewed—using the mean often results in about 70% of samples falling below it and 30% above, whereas the median splits the data evenly with 50% below and 50% above.

Example: Brain Fog

Here are some odds ratios using BiomeSight data. Odds Low means when the reading is below the Median and Odds High above the Median (of those with this symptom). We use the symptom median to get balanced (same approximate size) categories.

A few quick take away:

  • Probiotics such as Bifidobacterium, Ligilactobacillus, Lactococcus lactis, Lactiplantibacillus
    • Bifidobacterium catenulatum subsp. kashiwanohense (OR 1.37) is the preferred one!
    • Ligilactobacillus: Ligilactobacillus salivarius is the only one available retail
    • Lactiplantibacillus: Lactiplantibacillus plantarum is the only one available retail
    • Veillonella atypica is offered as FITBIOMICS V•Nella Lactic Acid Metabolizing Probiotic …
      • Note: Brain fog is often ascribed to too much Lactic Acid.
Tax_Nametax_RankOdds LowOdd High
Cerasicoccus arenaespecies1.590.71
Polyangiasubclass1.470.72
Lelliottiagenus1.420.75
Lelliottia amnigenaspecies1.420.75
Microcoleaceaefamily0.821.41
Myxococciaclass1.380.71
Myxococcalesorder1.380.71
Myxococcotaphylum1.380.71
Bifidobacterium catenulatum subsp. kashiwanohensesubspecies1.370.74
Denitratisomagenus0.871.37
Microcoleus antarcticusspecies0.811.36
Microcoleusgenus0.811.36
Desulfosporosinusgenus1.340.80
Trabulsiellagenus1.330.80
Rivulariaceaefamily1.320.79
Segatella paludivivensspecies1.320.79
Prosthecobactergenus1.320.73
Ligilactobacillusgenus1.310.77
Enterobacter cloacae complexspecies group1.300.80
Peptostreptococcus stomatisspecies1.300.80
Alcanivoraxgenus0.931.30
Alcanivoracaceaefamily0.931.30
Tepidanaerobacter syntrophicusspecies1.300.79
Tepidanaerobactergenus1.300.79
Tepidanaerobacteraceaefamily1.300.79
Hoylesella loescheiispecies1.290.81
Thermosediminibacteralesorder1.280.81
Enterobacter hormaecheispecies1.280.82
Slackia isoflavoniconvertensspecies0.841.27
Bifidobacterium choerinumspecies1.270.82
Desulfovibrio simplexspecies1.270.80
Chromatiumgenus0.901.27
Lactococcus fujiensisspecies1.270.67
Chromatium weisseispecies0.901.27
Klebsiellagenus1.270.82
Klebsiella/Raoultella groupno rank1.270.82
Veillonella atypicaspecies1.260.82
Isoalcanivoraxgenus0.941.26
Isoalcanivorax indicusspecies0.941.26
Schaalia turicensisspecies1.250.72
Lactococcus lactisspecies1.250.83
Bifidobacteriaceaefamily1.240.84
Bifidobacterialesorder1.240.84
Chloroflexotaphylum1.240.79
Salidesulfovibrio brasiliensisspecies0.921.24
Salidesulfovibriogenus0.921.24
Enterobactergenus1.240.81
Bifidobacteriumgenus1.240.84
Actinomycetotaphylum1.240.84
Acholeplasma hippikonspecies0.851.23
Mycoplasmataceaefamily1.230.82
Mycoplasmatalesorder1.230.82
Bifidobacterium angulatumspecies1.230.82
Clostridium nitrophenolicumspecies0.851.23
Bacteroides uniformisspecies0.851.22
Lactococcusgenus1.220.83
Lactiplantibacillusgenus1.220.84
Mycoplasmagenus1.220.82
Filifactor villosusspecies0.881.22
Anaerolineaeclass1.210.85
Veillonella denticariosispecies0.891.21
Actinomycetesclass1.210.85
Acidimicrobiumgenus1.210.79
Cerasicoccaceaefamily1.210.79
Cerasicoccusgenus1.210.79
Mycoplasmoidalesorder1.210.81
Parabacteroides gordoniispecies1.210.84
Thioalkalivibrio jannaschiispecies1.210.63
Candidatus Blochmanniella camponotispecies1.210.79
Thioalkalivibriogenus1.210.63
Acidimicrobiaceaefamily1.210.77
Bifidobacterium adolescentisspecies1.210.85
Bifidobacterium longumspecies1.210.85

That’s it for the moment

Also, see the links below for by-request tables

The next step is seeing how these odds ratio perform against samples and against the old algorithm. Stay tune.

Special note: This is not based on using averages of healthy populations, but more on the skewness of the distribution of those with the symptom. It is a different way of thinking about the issue.

caveat emptor

The table above applies only and exclusively with Biomesight data. For an explanation of why, see The taxonomy nightmare before Christmas… If you use a different lab, you will need to get that lab to crunch their numbers in the same manner as detailed above

Ghost Bacteria in 16s Reports

This morning I was trouble shooting an upload issue on Ombre CSV data — the reason was “they changed the format again!“. While triaging the issues I saw a lot of counts of “1” in the sample that I was working with. A count of 1 means that only one unit of bacteria was detected. Most microbiologists would deem that to be unreliable, the bacteria may not actually be present, i.e. a “Ghost Bacteria Identification”.

As a result, I look at the 16s tests that has been uploaded to compute the percentages of ghosts in samples.

16s Test fromAverage Lowest RateHighest RateBacteria Reported
Biomesight22.1%0%35.3%611
Ombre28.8%0%41.1%694
Medivere20.5%19%22.3%756
BiomeSightRdp11%1.9%20.0%476
CerbaLab13.9%0%24%Over 600
SequentiaBiotech1.4%0%5%313
CosmosId0.01%0%0.28%463

The numbers above suggests that reporting on ghosts results in more bacteria reports — which is a good marketing strategy. It is a questionable service to the consumers.

For myself, for my offline research database, I will be excluding counts of “1”. I may also offer an option to remove them on the upload page in the future. This is not a significant issue with shotgun reports.

“Buyer beware,” or caveat emptor 

From Perplexity (Click to get sources):

In 16S microbiome sequencing, counts of “1” (single read assigned to a taxon in a sample) are generally not considered reliable for determining the true presence of that organism. Here’s why:

  • Low-abundance signals (especially a single read) can easily result from sequencing errors, index hopping, cross-contamination, or misclassification in the bioinformatic pipeline.
  • Studies show that only OTUs (Operational Taxonomic Units) with higher counts (usually >10 reads, and especially >1% relative abundance) are consistently detected with high reliability and quantification accuracy.
  • Single-read taxa are much more likely to be false positives or background noise. They typically do not pass statistical filtering thresholds used in rigorous microbiome analysis.
  • Many pipelines recommend removing OTUs present in very low abundances (often <10 reads or <0.1–1% relative abundance) for reliable interpretation.

Summary:

  • Counts of “1” should be viewed as unreliable noise and not taken as meaningful evidence of that organism’s presence in your microbiome sample.
  • Reliable detection begins at much higher read counts and relative abundances, with reproducibility improving rapidly as counts increase.

Best practices:

  • Filter out taxa with extremely low counts for clinical or quantitative interpretation.
  • Use statistical and bioinformatic guidelines to set raw count and relative abundance thresholds for reporting results.

If you see a taxon with just one assigned read in your 16S data, consider it an artifact rather than true biological detection unless verified by other means.

Graphic Exploration into Significant Bacteria

Lazy versus Old School

I have observed that many data scientists tend to push data into a model and report the results of the model. I am old school and was taught to always chart the data to look for abnormalities. Doing that revealed that microbiome data is highly skewed. I covered this in Microbiologist / Data Scientist Guide to Bacterium Statistics.

I subsequently came across an odds plot where we have an appearance similar to electron shell densities and not the nice linear model that is often assumed.

The result was a clear need to review a lot more data graphically. There are the main patterns:

  • The condition line is clearly to the left of the reference line, i.e. transformed average is less
  • The condition line is clearly to the right of the reference line, i.e. transformed average is more
  • The condition line is on both sides of the reference line, i.e. a complex situation.
  • The lines are on top of each other — no association to the symptom

Lower Transformed Average

Higher Transformed Average

Mixed Case

No Association

A Video Show

I generated a program to walk through some random bacteria and recorded them in the video below. Pause the video when you want to look at a specific chart in greater detail. My main conclusion is that often a bacteria is significant only when it is in a certain range.

400+ more over 20 minutes

Autism Only

Long COVID

Mast Cell Activation Syndrome and Multiple Chemical Sensitivity

A person who suffered from Multiple Chemical Sensitivity(MCS) for many years before it progressed into Mast Cell Syndrome(MCAS) forward an article, “Chemical Intolerance and Mast Cell Activation: A Suspicious Synchronicity“, 2023. At the same time, my understanding of the complex nature of the microbiome also made a leap forward. For those interested, see these three very technical posts:

I decided to look at Mast Cell Activation Syndrome again in the hope of gaining insight into treatment possibilities.

The samples being using are donated by readers from various labs with symptoms being self-declared. Symptoms may not agree with clinical definitions. All of the data is freely available for those that are highly skilled with statistics at Citizen Science Distribution.

First, MCS::MCAS

With MCASWith MCSWITH MCAS and MCSWith Any Symptoms
Count305219623025
Percentage10%7.2%2%
  • If MCAS and MCS are independent, we would expect 10% x 7.2% or 0.72% overall. We have 3 times more than expected.
  • The chi-square statistic is 19.3693. The p-value is .000011. VERY SIGNIFICANT CONNECTION.

This disagrees on face value with the reported “Our outcomes confirm the previously published study where the majority of MCAS patients also have CI. ” For this to be true, With MCAS and MCS would be > 150. Differences in methodology may be the cause for this disagreement, but regardless, we see that a person with MCAS is around three times more likely to have had MCS. I read this as suggesting that MCS is a precursor for a class of MCAS. Having MCS prior is not required to developing MCAS; but having MCS means the odds of getting MCAS are much increased.

Looking at Bacterium

I am going to use samples processed through Biomesight only because it is the largest sample set.

For MCS

The table below is filtered to those with P < 0.001 at the genus level with the highest first (P < 5.19132E-05).

NameDirection
ActinocatenisporaLow
HathewayaHigh
ThaueraLow
DevosiaLow
ThiocapsaLow
DeferribacterLow
ViridibacillusLow
Candidatus TammellaLow
CoraliomargaritaLow
GeothrixLow
DesulfosporosinusLow
GlutamicibacterLow
DenitratisomaLow
CatenibacteriumLow
DesulforamulusLow
GeobacterLow
NeisseriaLow
NonomuraeaLow
AgromycesLow
AnaerotruncusHigh
OenococcusLow
SaccharopolysporaLow
LentibacillusLow

MCAS

The table below is filtered to those with P < 0.001 at the genus level with the highest first (P < 6.25726E-07).

NameDirection
EmticiciaLow
PseudoramibacterLow
ParascardoviaLow
RickettsiaLow
CalothrixLow
NonomuraeaLow
MarinospirillumLow
AzospirillumLow
NeisseriaLow
ViridibacillusLow
HelicobacterLow
PeptacetobacterLow
NitrosococcusLow
AvibacteriumLow
SchaaliaLow
PropionigeniumLow
FlammeovirgaLow
OligellaLow
ErysipelothrixHigh
GeobacterLow
CatenibacteriumLow
PontibacterLow
IsoalcanivoraxLow
FaecalitaleaLow
JonesiaLow
ThalassospiraLow
AmedibacillusHigh
ArthrobacterLow
HathewayaHigh

MCAS and MCS

The table below is filtered to those with P < 0.001 with the highest first (P < 1.85255E-05). The sample size is much smaller, so fewer items were significant, hence all ranks are shown.

NameRankDirection
ChloroflexotaphylumLow
AnaerolineaeclassLow
Eggerthella sinensisspeciesLow
DesulfofundulusgenusLow

Probiotic Remedies?

Because there are simply no published studies on most of the above bacterium, I went over to the R2 site to compute candidate probiotics. Note: Some of these probiotics are still in development or available only in some countries.

MCS

I enclosed the full list because you want to make sure NOT to take any with a Net being negative. Also, the safest are those with BAD being Zero (0)

Tax_NameTax_RankGoodBadNet
Christensenella minutaspecies19429165
Aspergillus oryzaespecies1380138
Faecalibacterium prausnitziispecies18578107
Anaerobutyricum halliispecies16258104
Enterococcus faeciumspecies1243787
Blautia hanseniispecies1223785
Lactiplantibacillus plantarumspecies64064
Roseburia intestinalisspecies1186058
Bifidobacterium catenulatumspecies53053
Priestia megateriumspecies47047
Bacillus pumilusspecies43043
Bacteroides thetaiotaomicronspecies37037
Latilactobacillus sakeispecies37037
Bifidobacterium brevespecies32032
Levilactobacillus brevisspecies31031
Parabacteroides distasonisspecies31031
Parabacteroides goldsteiniispecies542826
Pediococcus pentosaceusspecies25025
Limosilactobacillus reuterispecies23023
Shouchella clausiispecies23023
Lactiplantibacillus argentoratensisspecies23023
Bifidobacterium longumspecies20020
Bifidobacterium adolescentisspecies392118
Blautia wexleraespecies745717
Lactococcus cremorisspecies362115
Enterococcus faecalisspecies14014
Bifidobacterium pseudocatenulatumspecies13013
Limosilactobacillus vaginalisspecies12012
Lactobacillus kefiranofaciensspecies12012
Lactococcus lactisspecies11011
Clostridium beijerinckiispecies11011
Streptococcus thermophilusspecies10010
Leuconostoc mesenteroidesspecies10010
Segatella coprispecies37298
Phocaeicola coprocolaspecies27216
Bacillus subtilisspecies26215
Lactobacillus crispatusspecies11110
Lactiplantibacillus pentosusspecies011-11
Bacteroides uniformisspecies2032-12
Limosilactobacillus mucosaespecies014-14
Lacticaseibacillus caseispecies017-17
Bacillus cereusspecies3354-21
Bacillus licheniformisspecies022-22
Ligilactobacillus salivariusspecies1141-30
Lactobacillus jenseniispecies036-36
Akkermansia muciniphilaspecies1250-38

MCAS

Tax_NameTax_RankGoodBadNet
Christensenella minutaspecies83083
Aspergillus oryzaespecies68068
Enterococcus faeciumspecies58058
Faecalibacterium prausnitziispecies53053
Roseburia intestinalisspecies53053
Anaerobutyricum halliispecies51051
Blautia wexleraespecies44044
Bacillus pumilusspecies28028
Priestia megateriumspecies27027
Levilactobacillus brevisspecies25025
Latilactobacillus sakeispecies25025
Lactiplantibacillus argentoratensisspecies23023
Blautia hanseniispecies22022
Limosilactobacillus fermentumspecies21021
Shouchella clausiispecies20020
Limosilactobacillus reuterispecies18018
Lactiplantibacillus plantarumspecies17017
Bacillus subtilisspecies16016
Bifidobacterium animalisspecies15015
Bifidobacterium animalis subsp. lactissubspecies15015
Lactobacillus acidophilusspecies14014
Clostridium butyricumspecies13013
Bifidobacterium adolescentisspecies12012
Ligilactobacillus salivariusspecies11011
Hafnia alveispecies11011
Bacteroides uniformisspecies015-15
Lacticaseibacillus rhamnosusspecies016-16
Bacteroides fragilisspecies023-23

Bottom Line

The most confidence is to work on probiotics only with the following being strongly recommended.

  • Aspergillus oryzae
  • Enterococcus faecium
  • Bacillus pumilus
  • Bacillus subtilis
  • Lactiplantibacillus plantarum a.k.a. Lactobacillus plantarum
  • Bifidobacterium catenulatum
  • Bifidobacterium breve
  • Levilactobacillus brevis a.k.a. Lactobacillus brevis
  • Latilactobacillus sakei a.k.a. Lactobacillus sakei
  • Limosilactobacillus reuteri a.k.a. Lactobacillus reuteri
  • Shouchella clausii a.k.a. Bacillus Clausii
  • Lactobacillus acidophilus
  • Ligilactobacillus salivarius a.k.a. Lactobacillus salivarius

The top one for both is Aspergillus oryzae. This is likely unfamiliar to most people. It is also known as Shirayuri Koji. It is available on Amazon, not as a probiotic but cooking additive!! It is in Koji Rice. It is also solid as strong wakamoto w

With Tariffs ordering from Japan can get expensive, https://www.yami.com/ ships from the US, so no tariffs costs!

CAUTION: This is based on modelled data and not verified by clinical studies. IMHO, it is likely a superior set of suggestions than other more “conventional” approaches.

Using Mean and Standard Deviation for Bacteria is Inappropriate.

In an earlier post (Significant Bacteria and Their Thresholds – Part 1), I raised that issue and a EU colleague, Valentina Goretzki, suggested that I take data from 1 thousand shotgun samples from healthy individuals to illustrate the problem.

Microbiome data distributions frequently display extreme skewness—often greater than 20. In such cases, computing mean and standard deviation is simply incorrect.  My friend “Perplexity” writes Mean and standard deviation become inappropriate measures for computing significance if the distribution’s skewness is substantial—specifically, when the absolute skewness exceeds ±2.

The result was about two thousand bacterium that occurs at least 60 times in these samples could be plotted as shown below.

It is clear that non-parametric methods are needed to compute “healthy ranges”. For those with just basic statistics, this may become a significant challenge.