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Sample MDM Gut and Brain Health Test Report
Sample Report

MDM™ Gut and Brain Health Sample Report

See exactly what your results will look like, including bacterial and yeast markers, reference ranges, flagged values, and your personalized MDM Dysbiosis Score.

View Full Sample Report

Sample data shown for illustration purposes only. This is not an actual patient result.

Example of the MDM Dysbiosis Score summary box

What is the MDM Dysbiosis Score?

Alongside the full metabolite breakdown, every report includes one simple summary score. It shows how many of the tracked bacterial and yeast markers fall outside the normal range, giving you a quick, at a glance view of overall gut balance.

Metabolites Contained Within the MDM™ System

The MDM™ panel measures a set of microbial and host metabolites linked to gut health, dysbiosis, and the gut-brain axis. Select any metabolite below to read more.
Beta carboline (1-Methyl-1,2,3,4-tetrahydro-carboline-3-carboxylic acid)

This compound is made from tryptophan and may also be influenced by yeast activity in the gut. High levels may affect normal metabolism and brain function, although its effects are not yet well understood.

2-Hydroxyphenylacetic acid

An elevated level of 2-Hydroxyphenylacetic acid (2-HPAA) frequently signals intestinal dysbiosis or bacterial overgrowth of the small intestinal. This occurs when an overgrowth of unhealthful microbial flora in the intestines actively breaks down amino acids, particularly phenylalanine. By intercepting these nutrients before absorption, the microbial flora produce excess 2-HPAA as a byproduct and deplete the amino acids, often leading to low tyrosine levels.

3-Indole propionic acid

IPA is made when certain gut bacteria break down tryptophan. It can have beneficial effects in normal amounts, but abnormal levels may be a sign that the gut microbiome is out of balance.

3-Indoleacetonitrile

IAN is related to tryptophan metabolism and can come from both gut microbes and certain foods. Abnormal levels may reflect changes in diet or the gut microbiome, but its effects on the body are still not well understood.

5-Methoxyindole-3 acetic acid

5-MIAA is a compound related to tryptophan metabolism that may be influenced by the gut microbiome. Abnormal levels may be a sign that the way tryptophan is being processed has changed.

Hippuric acid

Hippuric acid is produced when the body processes compounds that often come from food and gut bacteria. Abnormal levels may reflect changes in the gut microbiome or in the body's ability to process these compounds.

Indole-3-acetic acid

IAA is produced when gut bacteria break down tryptophan. Abnormal levels may reflect changes in the gut microbiome and may affect communication between the gut, immune system, and brain.

Indole-3-acroylglycine

IAG is produced when gut bacteria break down tryptophan. Abnormal levels have been associated with digestive problems and changes in the intestinal barrier.

Indole-3-carboxaldehyde

This compound is produced when gut microbes break down tryptophan. It may help support the intestinal lining and immune system, while abnormal levels may indicate changes in gut microbial activity.

indole-3-lactic acid

ILA is made by several types of gut bacteria and may help support normal immune and intestinal function. Abnormal levels may reflect changes in the gut microbiome and its communication with the body.

Indoxyl sulfate

Indoxyl sulfate is harmful to the body, and is produced when gut bacteria break down tryptophan and the body processes the resulting compounds. High levels may be harmful and have been associated with oxidative stress, mitochondrial problems, and changes in gut and immune function.

Methylindole-3-acetic acid

Methyl 3-indole acetate is produced through bacterial metabolism and has been found at high levels in some people with autism. High levels may be a sign of an imbalance in gut microbial activity.

HPHPA

HPHPA is produced by certain gut bacteria and has been associated with changes in gut health and behavior. High levels may indicate an imbalance in the gut microbiome.

p-Cresol sulfate

P-cresol sulfate is a harmful compound produced when gut bacteria break down certain amino acids and the body processes the resulting compounds. High levels are likely harmful and have been associated with oxidative stress, mitochondrial problems, and gut imbalance.

Arabinitol

Arabinitol is produced mainly by yeast and fungi, including Candida. High levels may be a sign of increased yeast or fungal activity in the gut.

Citramalic acid

Citramalic acid is associated with yeast activity and has been found at higher levels in some people with autism. High levels may interfere with the body's normal energy-producing pathways.

Tartaric acid

Tartaric acid can come from foods, but high levels may also be associated with increased yeast or fungal activity. Large amounts may interfere with normal energy production and the body's use of important minerals.

Tricarbalyllic acid

Produced by aerobic bacteria, yeast, or Aspergillus species (mold). It binds to magnesium, potentially leading to a magnesium deficiency.

p-Ethylphenyl sulfate

4-EPS is produced when gut bacteria make certain compounds that are later processed by the body. High levels may indicate changes in the gut microbiome and have been linked in animal studies to changes in brain function and behavior.

Phenylacetylglutamine

A bacterial metabolite linked to urea cycle disorders and the removal of neurotoxic ammonia waste from the body. When a patient presents to an emergency room in hyperammonemia crisis, doctors administer sodium benzoate to remove excess NH4+. Phenylacetylglutamine is detected in urine.

Phenylalanine

Phenylalanine is an essential amino acid that the body uses to make important brain chemicals and hormones. Abnormal levels may result from diet, metabolism, or changes in how gut microbes use this amino acid.

Tryptophan

Tryptophan is an essential amino acid used to make important compounds involved in sleep, mood, immune function, and brain health. Gut microbes also use tryptophan, so abnormal levels may reflect changes in the balance between human and microbial metabolism.

Tyrosine

Tyrosine is an amino acid needed to make important brain chemicals and thyroid hormones. Abnormal levels may be related to diet, metabolism, or changes in how gut bacteria process tyrosine.

Scientific references
  1. C. K. Flynn et al., "Review of Elevated Para-Cresol in Autism and Possible Impact on Symptoms," Int. J. Mol. Sci., vol. 26, no. 4, p. 1513, Feb. 2025, doi: 10.3390/ijms26041513.
  2. Z. R. Hill, C. K. Flynn, and J. B. Adams, "Indoxyl Sulfate and Autism Spectrum Disorder: A Literature Review," Int. J. Mol. Sci., vol. 25, no. 23, p. 12973, Dec. 2024, doi: 10.3390/ijms252312973.
  3. K. Piatkov, T. Vu, C.-S. Hwang, and A. Varshavsky, "Formyl-methionine as a degradation signal at the N-termini of bacterial proteins," Microbial Cell, vol. 2, no. 10, pp. 376-393, Oct. 2015, doi: 10.15698/mic2015.10.231.
  4. E. A. Smith and G. T. Macfarlane, "Formation of Phenolic and Indolic Compounds by Anaerobic Bacteria in the Human Large Intestine," Springer-Verlag New York Inc, 1997.
  5. R. Close et al., "A Sulfotransferase from a Gut Microbe Acts on Diverse Phenolic Sulfate Compounds, Including Acetaminophen Sulfate," Jul. 07, 2025, doi: 10.1101/2025.07.07.663557.
  6. J. F. Xiao, B. Zhou, and H. W. Ressom, "Metabolite identification and quantitation in LC-MS/MS-based metabolomics," TrAC Trends in Analytical Chemistry, vol. 32, pp. 1-14, Feb. 2012, doi: 10.1016/j.trac.2011.08.009.
  7. R. J. Anderson et al., "Identification of indolyl-3-acryloylglycine in the urine of people with autism," Journal of Pharmacy and Pharmacology, vol. 54, no. 2, pp. 295-298, Feb. 2002, doi: 10.1211/0022357021778349.
  8. G. Bull et al., "Indolyl-3-acryloylglycine (IAG) is a putative diagnostic urinary marker for autism spectrum disorders," Med. Sci. Monit., vol. 9, no. 10, pp. CR422-5, Oct. 2003.
  9. J. B. Adams, T. Vargason, D. W. Kang, R. Krajmalnik-Brown, and J. Hahn, "Multivariate analysis of plasma metabolites in children with autism spectrum disorder and gastrointestinal symptoms before and after microbiota transfer therapy," Processes, vol. 7, no. 11, Nov. 2019, doi: 10.3390/pr7110806.
  10. D.-W. Kang, J. B. Adams, T. Vargason, M. Santiago, J. Hahn, and R. Krajmalnik-Brown, "Distinct Fecal and Plasma Metabolites in Children with Autism Spectrum Disorders and Their Modulation after Microbiota Transfer Therapy," mSphere, vol. 5, no. 5, Oct. 2020, doi: 10.1128/msphere.00314-20.
  11. P. Gatarek, J. Jozwik-Pruska, G. Bjorklund, S. Chirumbolo, and J. Kaluzna-Czaplinska, "Urinary carboxylic acids (UCAs) in subjects with autism spectrum disorder and their association with bacterial overgrowth," Rev. Anal. Chem., vol. 39, no. 1, pp. 78-87, Sep. 2020, doi: 10.1515/revac-2020-0109.
  12. K. Nirmalkar et al., "Bimodal distribution of intestinal Candida in children with autism and its potential link with worse ASD symptoms," Gut Microbes Reports, vol. 1, no. 1, Dec. 2024, doi: 10.1080/29933935.2024.2358324.
  13. H. Tsuchiya and T. Hayashi, "A possible link between beta-carboline metabolism and infantile autism," Med. Hypotheses, vol. 55, no. 3, pp. 215-217, Sep. 2000, doi: 10.1054/mehy.1999.1046.
  14. Y. Wang et al., "Health effects of exposure to beta-carboline heterocyclic amines: insight into metabolic perturbations and biochemical analysis," Food Funct., vol. 14, no. 9, pp. 4006-4016, 2023, doi: 10.1039/D2FO03722J.
  15. Y. Zheng et al., "The Role of Bacterial-Derived Aromatic Amino Acids Metabolites Relevant in Autism Spectrum Disorders: A Comprehensive Review," Front. Neurosci., vol. 15, Oct. 2021, doi: 10.3389/fnins.2021.738220.