Microbiome testing is promising, but consumer interpretation is still uneven.

Short answer

Some direct-to-consumer tests measure levels and types of bacterial flora, often referred to as the microbiome. FDA says direct-to-consumer tests vary in the evidence supporting their claims, and not all are reviewed before being offered for general wellness or low-risk uses.

Start here

Stool testing versus microbiome reports

A medical stool test and a consumer microbiome report can both use stool, but they answer different questions. Read the stool test versus microbiome test guide.

Food sensitivity panels

Many at-home food sensitivity tests use IgG panels that allergy organizations do not recommend for diagnosing food allergy or intolerance. Read the food sensitivity versus allergy testing guide.

Gut diversity scores

Gut diversity scores can be educational, but a high or low score is not a diagnosis by itself. Read the gut diversity score guide.

Probiotic recommendations

Microbiome reports may suggest probiotics, but useful evidence is often strain-specific and condition-specific. Read the probiotics and test-based recommendations guide.

Postbiotic claims

Postbiotic science is emerging, but a microbiome test does not automatically prove a supplement is clinically useful for you. Read the postbiotic testing claims guide.

Retesting intervals

There is no universal consumer microbiome retesting interval; the repeat test should answer a practical question. Read the microbiome retesting intervals guide.

Privacy and data sharing

Consumer microbiome tests may involve samples, microbial data, health questionnaires, app data, and research permissions. Read the microbiome test privacy guide.

Vaginal microbiome testing

Vaginal microbiome reports can add context, but symptoms, pregnancy, and possible STI exposure need medical testing questions. Read the vaginal microbiome testing guide.

After antibiotics

Antibiotics can change gut bacteria, but consumer retesting is most useful when it answers a clear practical question. Read the microbiome testing after antibiotics guide.

SIBO breath testing

SIBO breath tests measure hydrogen and methane patterns, but preparation, transit time, symptoms, and risk factors change interpretation. Read the SIBO breath test guide.

Leaky gut claims

Intestinal permeability is real research, but consumer leaky gut panels often overstate what zonulin, stool, or permeability tests can prove. Read the leaky gut testing guide.

Digestive enzyme claims

Digestive enzyme testing is strongest for specific pancreatic questions, not broad supplement recommendations for everyday bloating. Read the digestive enzyme testing guide.

Fecal calprotectin

Fecal calprotectin can help evaluate intestinal inflammation and IBD-vs-IBS questions, but it is not a general gut-health score. Read the fecal calprotectin guide.

Fecal calprotectin versus lactoferrin

Fecal calprotectin and lactoferrin both reflect intestinal inflammation and can help decide when an IBD workup needs more attention. Read the calprotectin versus lactoferrin guide.

Stool WBC tests

Stool white blood cell testing looks for signs of intestinal inflammation, but it is only one piece of an infectious or inflammatory diarrhea workup. Read the stool WBC and inflammatory diarrhea guide.

H. pylori

H. pylori testing includes breath, stool antigen, blood antibody, and biopsy options, and the test type matters before and after treatment. Read the H. pylori testing guide.

Celiac blood tests

Celiac disease screening usually starts with blood tests such as tTG-IgA and total IgA, ideally before removing gluten. Read the celiac disease blood tests guide.

GI pathogen panels

GI pathogen panels can quickly check many infectious diarrhea causes, but PCR results still need symptom and public-health context. Read the GI pathogen panel guide.

Lactose intolerance breath tests

Lactose breath testing can help when the question is whether lactose-containing foods trigger bloating, diarrhea, gas, or cramps. Read the lactose breath test guide.

Pancreatic elastase

Pancreatic elastase is a targeted stool test for exocrine pancreatic insufficiency, not a broad wellness score. Read the pancreatic elastase guide.

Bile acid malabsorption

Bile acid malabsorption testing belongs in chronic watery diarrhea workups, especially when IBS-D overlap or post-gallbladder patterns are possible. Read the bile acid malabsorption testing guide.

Fructose breath testing

Fructose breath testing can support a targeted diet question, but dose, SIBO, transit, and symptom context matter. Read the fructose breath test guide.

Fecal occult blood and FIT tests

FIT and fecal occult blood tests look for hidden blood in stool, often for colorectal cancer screening, and positive results need the right follow-up. Read the FIT and fecal occult blood guide.

Stool ova and parasite testing

Ova and parasite testing is most useful when exposure history, symptoms, travel, or immune risk make parasites plausible. Read the stool O&P guide.

Giardia antigen testing

Giardia antigen testing is a targeted stool test for a common parasite that can cause diarrhea after contaminated water, childcare, travel, or close-contact exposure. Read the Giardia antigen test guide.

Cryptosporidium stool testing

Cryptosporidium testing may require a specific stool antigen, microscopy, or PCR request, and multiple samples can matter because shedding may be intermittent. Read the Cryptosporidium stool test guide.

Cyclospora stool testing

Cyclospora is not routinely tested for by many labs, so prolonged or outbreak-linked diarrhea may need a specific stool test request. Read the Cyclospora stool test guide.

Enteric parasite PCR panels

Enteric parasite PCR panels can quickly check selected stool parasite targets, but the result only covers organisms included by that panel. Read the enteric parasite PCR panel guide.

Norovirus stool testing

Norovirus testing is often most useful when RT-qPCR on whole stool changes outbreak response, infection-control steps, or the differential diagnosis. Read the norovirus stool test guide.

Adenovirus stool testing

Adenovirus stool testing can help when gastroenteritis is clinically significant and the lab question is enteric adenovirus rather than a broad microbiome score. Read the adenovirus stool test guide.

Rotavirus stool testing

Rotavirus stool testing may use antigen or PCR methods, but the result is most useful when age, vaccination, dehydration risk, and outbreak setting change what happens next. Read the rotavirus stool test guide.

Sapovirus stool testing

Sapovirus stool testing is usually part of an acute viral gastroenteritis or outbreak workup, especially when norovirus-like illness remains unexplained. Read the sapovirus stool test guide.

Astrovirus stool testing

Astrovirus stool testing uses molecular methods or GI panels to help explain selected acute gastroenteritis episodes and outbreaks. Read the astrovirus stool test guide.

Campylobacter stool testing

Campylobacter stool testing can use culture or molecular panels when diarrhea is severe, persistent, bloody, outbreak-related, or clinically important. Read the Campylobacter stool test guide.

Salmonella stool testing

Salmonella stool testing helps confirm suspected salmonellosis, guide public-health follow-up, and decide whether further testing or treatment questions matter. Read the Salmonella stool test guide.

Shigella stool testing

Shigella stool testing can use culture or molecular panels, and resistance follow-up may matter when antibiotics or public-health steps are being considered. Read the Shigella stool test guide.

Shiga toxin and STEC stool testing

Shiga toxin and STEC stool testing is important in acute diarrhea because E. coli O157, non-O157 STEC, and HUS risk change follow-up decisions. Read the Shiga toxin and STEC stool test guide.

Yersinia stool testing

Yersinia stool testing may need special culture handling or an included PCR target, especially when pseudoappendicitis, pork exposure, or iron-overload risk fits. Read the Yersinia stool test guide.

Vibrio stool testing

Vibrio stool testing matters after seafood or saltwater exposure, and species identification can change urgency and treatment decisions. Read the Vibrio stool test guide.

Entamoeba histolytica stool testing

Entamoeba histolytica testing needs species-level care because microscopy can confuse pathogenic and nonpathogenic Entamoeba. Read the Entamoeba histolytica stool test guide.

Strongyloides antibody versus stool testing

Strongyloides can be missed on a single stool exam, so antibody testing matters when exposure risk or upcoming immunosuppression fits. Read the Strongyloides antibody versus stool test guide.

Pinworm tape testing

Pinworm testing usually uses a first-morning tape sample from skin near the anus because routine stool samples can miss eggs. Read the pinworm tape test guide.

Hookworm stool testing

Hookworm is commonly diagnosed by finding eggs in stool, with anemia, eosinophils, travel, and soil exposure shaping suspicion. Read the hookworm stool test guide.

Ascaris stool testing

Ascaris stool testing looks for roundworm eggs under the microscope, usually with exposure history and repeat specimens shaping confidence. Read the Ascaris stool test guide.

Trichuris stool testing

Trichuris, or whipworm, is usually diagnosed by identifying eggs in stool, with diarrhea, anemia, soil exposure, and specimen strategy guiding follow-up. Read the Trichuris stool test guide.

Taenia tapeworm stool testing

Taenia tapeworm stool testing looks for eggs or proglottids, but species identification can require careful lab review and exposure context. Read the Taenia tapeworm stool test guide.

Schistosoma testing

Schistosoma testing depends on the suspected species and exposure, with stool, urine, and antibody testing playing different roles. Read the Schistosoma testing guide.

Echinococcus antibody testing

Echinococcus antibody testing is usually interpreted with cyst imaging and exposure history rather than as a broad parasite screen. Read the Echinococcus antibody testing guide.

Toxocara antibody testing

Toxocara antibody testing can help when exposure, eosinophils, visceral symptoms, or eye findings suggest toxocariasis. Read the Toxocara antibody testing guide.

Chagas disease antibody testing

Chagas disease antibody testing is a targeted Trypanosoma cruzi serology question shaped by geography, donor screening, pregnancy, or compatible organ findings. Read the Chagas disease antibody testing guide.

Loa loa blood smear testing

Loa loa blood smear testing depends on West or Central Africa exposure and timed daytime blood collection. Read the Loa loa blood smear testing guide.

Filaria antibody testing

Filaria antibody testing can support selected filarial worm workups, but geography and cross-reactivity shape interpretation. Read the filaria antibody testing guide.

Cysticercosis antibody testing

Cysticercosis antibody testing is usually interpreted with CT or MRI findings when neurocysticercosis is suspected. Read the cysticercosis antibody testing guide.

Trypanosoma brucei testing

Trypanosoma brucei testing is an urgent African sleeping sickness workup shaped by tsetse exposure, specimen choice, and possible CSF staging. Read the Trypanosoma brucei testing guide.

Baylisascaris antibody testing

Baylisascaris antibody testing is a rare public-health supported workup interpreted with exposure history, eye findings, neurologic symptoms, and eosinophils. Read the Baylisascaris antibody testing guide.

Paragonimus antibody testing

Paragonimus antibody testing supports selected lung-fluke workups when food exposure, eosinophils, sputum or stool microscopy, and imaging fit. Read the Paragonimus antibody testing guide.

Gnathostoma antibody testing

Gnathostoma antibody testing is limited and specialist-guided when migratory swelling, eosinophils, raw fish exposure, or neurologic symptoms raise concern. Read the Gnathostoma antibody testing guide.

Fasciola antibody testing

Fasciola antibody testing helps selected liver-fluke workups before stool eggs are detectable. Read the Fasciola antibody testing guide.

Clonorchis and Opisthorchis antibody testing

Clonorchis and Opisthorchis testing is shaped by raw freshwater fish exposure, stool ova, liver tests, and bile-duct findings. Read the Clonorchis and Opisthorchis testing guide.

Anisakis allergy and antibody testing

Anisakis testing depends on whether the question is acute anisakiasis after raw fish or allergic sensitization. Read the Anisakis allergy and antibody testing guide.

Angiostrongylus testing

Angiostrongylus testing is a specialist rat lungworm workup shaped by eosinophilic meningitis, exposure history, and reference-lab options. Read the Angiostrongylus testing guide.

Diphyllobothrium tapeworm testing

Diphyllobothrium testing is a targeted stool-based workup for broad fish tapeworm questions after raw or undercooked fish exposure, visible segments, or B12-related clues. Read the Diphyllobothrium tapeworm testing guide.

Strongyloides treatment follow-up testing

Strongyloides follow-up testing depends on the original positive test, symptoms, eosinophil trend, treatment, and immunosuppression risk. Read the Strongyloides treatment follow-up testing guide.

Hymenolepis nana tapeworm testing

Hymenolepis nana testing is a targeted stool ova and parasite workup for dwarf tapeworm questions, especially with exposure, children, household spread, or recurrent symptoms. Read the Hymenolepis nana tapeworm testing guide.

Enterobius pinworm treatment follow-up testing

Enterobius follow-up is usually about tape testing, nighttime itching, household treatment, and reinfection prevention rather than broad stool panels. Read the Enterobius pinworm follow-up testing guide.

Dientamoeba fragilis stool testing

Dientamoeba fragilis testing depends on symptom fit, stool handling, and whether microscopy or PCR is being used. Read the Dientamoeba fragilis stool testing guide.

Blastocystis stool test interpretation

Blastocystis results need careful interpretation because detection can mean colonization, uncertain clinical relevance, or a possible clue in persistent symptoms. Read the Blastocystis stool test interpretation guide.

Microsporidia stool and PCR testing

Microsporidia testing is a targeted workup for chronic diarrhea or extraintestinal concerns, especially when immune status changes risk and the lab needs a special stain or PCR target. Read the Microsporidia stool and PCR testing guide.

Cyclospora repeat testing after treatment

Cyclospora repeat testing depends on persistent symptoms, specimen timing, intermittent shedding, and whether PCR or microscopy was used. Read the Cyclospora repeat testing guide.

Cystoisospora stool testing

Cystoisospora testing usually needs a targeted parasite question, especially with prolonged watery diarrhea, immune risk, travel, or a request for special stains or PCR. Read the Cystoisospora stool testing guide.

Giardia treatment follow-up testing

Giardia follow-up testing is most useful when symptoms persist or recur after treatment, reinfection is plausible, or the original method needs confirmation. Read the Giardia follow-up testing guide.

Entamoeba dispar versus histolytica testing

Entamoeba testing needs species-level care because microscopy can group pathogenic E. histolytica with nonpathogenic look-alikes such as E. dispar. Read the Entamoeba dispar versus histolytica testing guide.

Stool PCR positive after symptoms resolve

A positive stool PCR after diarrhea improves can reflect shedding, colonization, timing, or organism-specific public-health rules rather than active disease by itself. Read the stool PCR positive after symptoms resolve guide.

Stool PCR co-detection interpretation

Multiple positives on a stool PCR panel need clinical correlation because co-detection can mean coinfection, shedding, colonization, or a target that is not driving symptoms. Read the stool PCR co-detection interpretation guide.

Stool PCR negative with persistent diarrhea

A negative stool PCR narrows the infectious question but does not rule out organisms outside the panel, collection timing issues, parasites needing targeted tests, or noninfectious causes. Read the stool PCR negative with persistent diarrhea guide.

Stool PCR E. coli pathotype interpretation

E. coli pathotype results such as ETEC, EPEC, EAEC, STEC, or EIEC/Shigella need symptom, travel, co-detection, and Shiga toxin context before action. Read the stool PCR E. coli pathotype interpretation guide.

Post-infectious IBS testing questions

Post-infectious IBS is considered after ongoing infection, inflammation, celiac disease, malabsorption, and red flags have been weighed against the symptom pattern. Read the post-infectious IBS testing questions guide.

Stool PCR C. difficile co-detection interpretation

C. difficile co-detection on a stool PCR panel needs diarrhea criteria, toxin context, medication timing, and colonization risk before deciding what the result means. Read the stool PCR C. difficile co-detection guide.

Stool PCR norovirus positive interpretation

A positive norovirus stool PCR is strongest when symptoms and exposure timing fit, but PCR can also stay positive during viral shedding after recovery. Read the stool PCR norovirus positive guide.

Stool PCR sapovirus positive interpretation

A positive sapovirus PCR is interpreted through acute viral gastroenteritis symptoms, outbreak context, co-detections, hydration risk, and timing of collection. Read the stool PCR sapovirus positive guide.

Stool PCR astrovirus positive interpretation

A positive astrovirus PCR is strongest when symptoms fit viral gastroenteritis, especially in children, older adults, immunocompromised people, or outbreak settings. Read the stool PCR astrovirus positive guide.

Stool PCR rotavirus positive interpretation

A positive rotavirus PCR is interpreted with acute vomiting or diarrhea, age, vaccination context, dehydration risk, co-detections, and outbreak setting. Read the stool PCR rotavirus positive guide.

Stool PCR adenovirus positive interpretation

A positive adenovirus stool PCR needs enteric adenovirus context, specimen type, co-detections, immune risk, and whether symptoms fit gastroenteritis. Read the stool PCR adenovirus positive guide.

Stool PCR Campylobacter positive interpretation

A positive Campylobacter PCR is strongest when symptoms and exposure fit, but reflex culture can still matter for susceptibility and public-health questions. Read the stool PCR Campylobacter positive guide.

Stool PCR Salmonella positive interpretation

A positive Salmonella PCR is interpreted with symptom timing, risk factors, shedding, and whether reflex culture is needed for susceptibility or outbreak tracking. Read the stool PCR Salmonella positive guide.

Stool PCR Shigella positive interpretation

A positive Shigella PCR needs symptom, public-health, resistance, and reflex-culture context, especially because some panels overlap with EIEC. Read the stool PCR Shigella positive guide.

Stool PCR STEC positive interpretation

A positive STEC PCR is interpreted with Shiga toxin, O157, bloody diarrhea, kidney-risk, and antibiotic-caution context. Read the stool PCR STEC positive guide.

Stool PCR Yersinia positive interpretation

A positive Yersinia PCR should be matched to diarrhea, abdominal pain, iron-risk context, and whether special culture handling or public-health follow-up is needed. Read the stool PCR Yersinia positive guide.

Stool PCR Vibrio positive interpretation

A positive Vibrio PCR needs seafood, seawater, wound, liver-disease, species, and culture-confirmation context before it is treated as a complete answer. Read the stool PCR Vibrio positive guide.

Stool PCR Plesiomonas positive interpretation

A positive Plesiomonas PCR should be matched to symptoms, travel, water exposure, co-detections, and whether culture information would change follow-up. Read the stool PCR Plesiomonas positive guide.

Stool PCR Aeromonas positive interpretation

A positive Aeromonas PCR is interpreted with diarrhea severity, water or wound exposure, co-detections, and whether susceptibility information is needed. Read the stool PCR Aeromonas positive guide.

Stool PCR Entamoeba histolytica positive interpretation

A positive E. histolytica PCR is interpreted with dysentery, travel, species specificity, co-detections, and possible liver involvement. Read the stool PCR Entamoeba histolytica positive guide.

Stool PCR Giardia positive interpretation

A positive Giardia PCR should be tied to symptoms, water or household exposure, co-detections, transmission prevention, and follow-up if symptoms persist. Read the stool PCR Giardia positive guide.

Stool PCR Cryptosporidium positive interpretation

A positive Cryptosporidium PCR is interpreted with watery diarrhea, water or daycare exposure, immune risk, co-detections, and dehydration. Read the stool PCR Cryptosporidium positive guide.

Stool PCR Cyclospora positive interpretation

A positive Cyclospora PCR fits prolonged or relapsing watery diarrhea, produce or travel exposure, public-health context, and treatment follow-up. Read the stool PCR Cyclospora positive guide.

Stool PCR enterotoxigenic E. coli positive interpretation

A positive ETEC PCR is interpreted with watery diarrhea, travel or food exposure, co-detections, dehydration risk, and red flags. Read the stool PCR ETEC positive guide.

Stool PCR parasite panel false negative questions

A negative parasite PCR panel only covers its target list and may need repeat specimens or targeted follow-up when exposure suspicion remains high. Read the parasite panel false-negative guide.

Stool PCR enteroaggregative E. coli positive interpretation

A positive EAEC PCR can fit persistent or travel-associated diarrhea, but co-detections and symptom fit are especially important. Read the stool PCR EAEC positive guide.

Stool PCR enteropathogenic E. coli positive interpretation

A positive EPEC PCR can be clinically ambiguous, especially in adults or when other organisms are detected on the same panel. Read the stool PCR EPEC positive guide.

Stool PCR enteroinvasive E. coli/Shigella positive interpretation

A positive EIEC/Shigella PCR should be read with symptoms, dysentery clues, co-detections, exposure risk, and public-health context. Read the stool PCR EIEC/Shigella positive guide.

Stool PCR C. difficile toxin gene positive interpretation

A positive C. difficile toxin gene PCR is most meaningful when new watery diarrhea and risk factors fit; otherwise colonization is possible. Read the C. difficile toxin gene PCR guide.

C. difficile toxin negative but NAAT positive

A toxin-negative but NAAT-positive C. difficile result can mean colonization or infection depending on stool consistency, symptoms, and risk factors. Read the C. difficile toxin-negative NAAT-positive guide.

Stool PCR E. coli co-detection questions

Multiple E. coli pathotype detections should be interpreted with symptoms, travel, stool type, co-detections, and public-health context. Read the stool PCR E. coli co-detection guide.

C. difficile repeat testing questions

Repeat C. difficile testing is usually a symptom and recurrence question, not a routine test-of-cure habit. Read the C. difficile repeat testing guide.

Stool PCR travel diarrhea co-detection questions

Travel diarrhea PCR panels often find more than one target, so timing, region, severity, and organism type matter. Read the travel diarrhea co-detection guide.

Stool PCR antibiotic-associated diarrhea co-detection questions

Antibiotic-associated diarrhea with multiple PCR hits should be sorted by C. difficile toxin context, symptoms, timing, and whether another pathogen better fits. Read the antibiotic-associated diarrhea co-detection guide.

Stool PCR post-infectious IBS questions

Post-infectious IBS is considered only after red flags, ongoing infection, panel limits, shedding, and noninfectious causes are weighed. Read the stool PCR post-infectious IBS guide.

Stool culture versus PCR panels

Stool culture and PCR panels can both help with infectious diarrhea, but speed, organism viability, susceptibility testing, and public-health follow-up differ. Read the stool culture versus PCR guide.

C. diff testing

C. diff testing is most useful when new unformed stools and risk factors fit infection, because positive molecular results can also reflect colonization. Read the C. diff testing guide.

Fecal fat testing

Fecal fat testing can help evaluate fat malabsorption when greasy stools, chronic diarrhea, weight loss, or nutrition concerns fit the picture. Read the fecal fat test guide.

Stool pH and reducing substances

Stool pH and reducing substances can be clues in selected pediatric diarrhea workups, but they are weak stand-alone tests for adult gut optimization. Read the stool pH and reducing substances guide.

Stool electrolytes and osmotic gap

Stool electrolytes and osmotic gap testing can help separate osmotic from secretory patterns in selected chronic watery diarrhea workups. Read the stool electrolytes and osmotic gap guide.

What to evaluate

• What sample is collected and how stable it is during shipping.
• Whether the company reports raw taxa, diversity scores, or specific health claims.
• Whether recommendations are based on validated clinical evidence or general wellness associations.
• Whether the report tells you what should not be concluded from the result.