People with inflammatory bowel disease (IBD) appear to have fewer gut bacteria that produce queuine, a vitamin-like nutrient, along with lower activity in the pathways that make it. An analysis of 9 public microbiome datasets and about 3,146 samples suggests this shortfall may contribute to IBD, but the work is an unreviewed preprint.
Researchers reanalyzed existing gut microbiome and cell datasets to examine a vitamin-like nutrient called queuine, which the body gets from gut bacteria and food. The study found that people with inflammatory bowel disease (IBD) had fewer of the bacteria that produce queuine, including Bacteroides and Alistipes, and lower activity in the pathways used to make it. Intestinal cells in people with IBD also showed reduced levels of a gene needed to use queuine. According to research reviewed by Gram, these patterns suggest a possible link between queuine and IBD, but this work is a preprint that has not yet been peer reviewed. The findings point to a question worth testing, not a treatment that can be recommended today.
Key Statistics
A 2026 preprint reanalysis of 9 public gut microbiome datasets, including about 3,146 samples, found that people with inflammatory bowel disease had significantly fewer queuine-producing bacteria than healthy people.
A 2026 preprint analysis of 15 single-cell RNA sequencing datasets reported that QTRT1, a gene needed to use queuine, was significantly lower in intestinal cells of people with IBD compared with healthy controls.
The Quick Take
- What they studied: The researchers asked whether a shortage of queuine, a vitamin-like nutrient made with help from gut bacteria, might be connected to inflammatory bowel disease.
- Who participated: The team did not recruit new people. They reanalyzed public data from 9 gut microbiome studies, 15 cell studies, and 1 metabolic study, including about 3,146 stool samples from people of different ages, both healthy and with IBD.
- Key finding: People with IBD had clearly fewer queuine-producing bacteria and lower activity in the related chemical pathways than healthy people. Intestinal cells in people with IBD also showed lower levels of a gene needed to use queuine. These are patterns in the data, not proof that low queuine causes IBD.
- What it means for you: This research does not show that taking queuine or changing your diet will prevent or treat IBD. If you have IBD or digestive symptoms, talk with your doctor before trying any supplement or major diet change.
The Research Details
This study was a secondary analysis, meaning the researchers did not collect new samples. Instead, they combined and reanalyzed large public collections of data. They looked at the genetic material of gut bacteria from stool samples, which shows which microbes are present and what chemical tasks they can perform. They also examined gene activity data from individual intestinal cells.
To measure queuine production, the team sorted bacteria by the genes they carry and checked whether those genes can build queuine or the related molecules. They compared these patterns between healthy people and people with IBD, and they tracked how the bacteria changed across different ages. The analysis used a standard method that estimates which biological pathways are active based on the genes present.
Because the work combined many separate datasets, the researchers could look for patterns that appear across different groups of people. This approach can reveal consistent trends, but it depends on how well the original studies were designed and measured.
Combining many datasets helps reduce the chance that a finding comes from one small group or one lab’s methods. If the same pattern appears across multiple independent studies, it is more believable than a single result. This is especially useful for gut microbiome research, where results from one study often vary.
The approach also looks at what bacteria do, not only which bacteria are present. Two people can have similar bacteria but very different chemical outputs, so checking function adds useful information.
This work is a preprint posted on medRxiv, which means it has not yet been reviewed by independent experts for publication. Preprints can be valuable for sharing early ideas, but their conclusions may change after review.
The study uses existing data, so it can show associations but cannot prove that low queuine causes IBD. The exact sample size is not clearly stated in the study details, although the abstract describes datasets including about 3,146 samples. Readers should treat the results as a hypothesis that needs testing in people.
What the Results Show
The researchers first identified bacteria that appear to produce queuine in healthy people. Bacteroides and Alistipes were among the most important of these microbes. Their results suggest that these bacteria help supply the chemical building blocks needed for queuine.
When they compared people with IBD to healthy people, the IBD group had significantly fewer queuine-producing bacteria. The study also found lower activity across several related pathways, including those that make queuine and other molecules involved in building genetic material. The researchers reported that the drop was mainly linked to reduced contributions from Bacteroides, Alistipes, and Akkermansia.
The team also looked at intestinal cells and found that QTRT1, a gene that helps cells use queuine in their genetic messages, was significantly lower in people with IBD than in healthy controls. This suggests that the body may have less ability to use queuine when it is present. Together, these findings describe a possible chain: fewer producing bacteria, less queuine supply, and reduced cellular use.
The study also reported a negative link between age and queuine-producing bacteria in people with ulcerative colitis, a type of IBD. In other words, these bacteria appeared to decline as people got older in that group. This pattern needs more study before its meaning is clear.
The researchers suggested that the pattern of fewer queuine-producing bacteria may be a form of microbial imbalance, sometimes called dysbiosis, that is specific to how the gut functions rather than just which species are present. This idea may help explain why IBD is linked to changes in gut chemistry, not only to changes in bacterial names.
The authors also noted that queuine is an important micronutrient, meaning the body needs it in small amounts. Because it can come from both gut bacteria and food, diet and microbes may work together. Still, the study did not directly measure how much queuine people eat or how much their bodies contain.
Previous research has repeatedly found that people with IBD have altered gut bacteria, often with lower diversity and fewer beneficial microbes. This study adds a new angle by focusing on what those bacteria can make, especially queuine. Queuine has been studied mainly in laboratory and cell research, so connecting it to human IBD is a newer and less established area.
The findings also fit with the broader idea that gut microbes influence human cells through nutrients and chemical signals. However, because the queuine link is new, it should be viewed as a promising direction rather than a confirmed explanation for IBD.
The biggest limitation is that this is a preprint and has not been peer reviewed. The study also relies on data collected by other researchers, which may differ in how samples were collected, stored, and analyzed.
The study shows associations, meaning patterns that occur together. It cannot tell whether fewer queuine-producing bacteria cause IBD, result from it, or are affected by a third factor such as inflammation, medications, or diet. People with IBD often take antibiotics or other drugs that can change gut bacteria, and these effects can be hard to separate from the disease itself.
The team did not test whether giving queuine or changing queuine levels improves IBD symptoms. Finally, some numbers and sample details are not clearly reported in the study description, so the exact strength of the findings is difficult to judge.
The Bottom Line
Confidence level: low for practical recommendations. The research supports the idea that queuine-producing gut bacteria are lower in people with IBD, but it does not yet show that restoring queuine helps. No specific supplement dose or diet plan can be recommended based on this study. Researchers would need controlled human trials to test whether queuine levels affect IBD outcomes.
For general gut health, eating a varied diet with plenty of fiber from vegetables, fruits, beans, and whole grains supports a diverse gut microbiome. This advice is widely supported by other research, though it is not specific to queuine.
People with IBD, their families, and clinicians may find this research interesting as an emerging area of study. Researchers studying gut microbes, nutrition, and inflammation should also pay attention to the queuine pathway.
People without digestive symptoms do not need to change their habits based on this study alone. Anyone considering queuine supplements should speak with a doctor first, especially if they have IBD or take medications.
Findings like these usually take years to move from early observations to tested treatments. If future studies confirm the link, researchers would still need to run clinical trials to test safety, dosing, and whether any benefit lasts. For readers, the most realistic expectation is to watch for peer-reviewed follow-up studies rather than expecting changes to care soon.
Frequently Asked Questions
What is queuine and why does it matter for gut health?
Queuine is a vitamin-like micronutrient that the body gets from gut bacteria and some foods. It helps cells build certain molecules used to make proteins. Researchers are now studying whether low queuine activity may be linked to inflammatory bowel disease, though this link is not yet confirmed.
Can taking queuine supplements help treat IBD?
No human trials have shown that queuine supplements treat IBD. A 2026 preprint found fewer queuine-producing gut bacteria in people with IBD, but it did not test supplements. Anyone with IBD should consult a doctor before trying any new supplement.
Which gut bacteria produce queuine?
The preprint identified Bacteroides and Alistipes as key queuine-producing bacteria in healthy people. People with IBD had reduced contributions from these bacteria and from Akkermansia, according to the reanalysis of multiple microbiome datasets.
Is this IBD and queuine research peer reviewed?
Not yet. The study is a preprint posted on medRxiv, which means independent experts have not formally reviewed it for publication. Its results should be treated as early findings that need confirmation in peer-reviewed research and clinical studies.
Want to Apply This Research?
- Log daily fiber servings (for example, servings of vegetables, fruits, beans, and whole grains) and any digestive symptoms on a simple 1 to 5 scale. Review patterns weekly to see whether symptom changes follow diet changes. Share these logs with a healthcare provider rather than using them to diagnose or adjust treatment.
- Add one extra serving of fiber-rich food each day, such as beans, lentils, oats, or vegetables, and track how you feel over two to four weeks. Avoid starting queuine supplements based on this research, and check with a doctor before making any change if you have IBD.
- Over several months, track diet patterns, digestive symptoms, medications, and any medical test results your doctor shares. Update the app when new peer-reviewed studies on queuine and gut bacteria are published, and review the findings with a healthcare professional before acting on them.
This article summarizes a preprint that has not been peer reviewed, and its findings may change. It is for general education only and is not medical advice. People with inflammatory bowel disease or digestive symptoms should talk with a doctor or registered dietitian before starting supplements, changing diet, or stopping any medication.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.