Research Gut Microbiome

The Human Gut Microbiome in Health and Disease

This study explains that our gut is home to trillions of microbes—mostly bacteria—that play a vital role in our health. These microbes help digest food that our bodies can’t break down on their own, produce important vitamins like B and K, and support the immune system. They also send signals to other parts of the body, including the brain. When the balance of these microbes is disturbed (a condition called dysbiosis), it can lead to issues like gut disorders, obesity, and diabetes. Overall, the gut microbiota acts like a hidden organ, helping to keep the body running smoothly.

Small intestine vs. colon ecology and physiology: Why it matters in probiotic administration

The article titled "Small intestine vs. colon ecology and physiology: Why it matters in microbiome research" discusses the differences between the small intestine and the colon in terms of their structure, function, and microbial communities. It highlights how the small intestine has a more diverse microbiota due to its unique environment, including factors like nutrient availability and immune responses. Understanding these differences is crucial for microbiome research, as it can impact the interpretation of microbial roles in health and disease. The article emphasizes the need for more focused studies on the small intestine to gain a comprehensive understanding of the human microbiome.

20 Things you Didn’t Know About the Human gut Microbiome

This brief review reveals insights into the human gut microbiome—an ecosystem of roughly 100 trillion microorganisms spanning up to 5,000 species that outnumber our own cells and weigh about two kilograms—and emphasizes that it's a metabolic and immune "organ" in its own right. It highlights how advances in DNA sequencing and metagenomics have shifted understanding from simply cataloging which microbes are present to exploring what they actually do.

Interplay between gut microbiota and antimicrobial peptides

The article explains how the gut microbiome and antimicrobial peptides—small proteins produced by the body’s immune cells and gut lining—work closely together to maintain a healthy intestinal environment. These peptides help control microbial populations, preventing harmful pathogens from overgrowing, while the microbiome itself can influence how these peptides are produced. Disruption in this interplay—due to factors like poor diet, infection, or inflammation—can lead to imbalances linked to gastrointestinal disease, allergies, and metabolic disorders.

Healthy soils for healthy plants for healthy humans

This article talks about how healthy soil helps grow healthy plants, and in turn, healthy plants help keep people healthy. It explains that tiny helpful microbes living in soil and around plant roots are similar to those in our gut and are important for good nutrition and a strong immune system. The article says that farming methods that protect these good soil microbes can lead to better food and better health for humans. It suggests that taking care of soil health should be a priority to support overall well-being.

The gut microbiome of healthy long-living people

The article investigates the gut microbiota of elderly individuals who maintain good health and longevity. It highlights that, in contrast to the general trend of reduced microbial diversity with age, these individuals exhibit a more balanced and diverse gut microbiome. This distinct microbiome composition is associated with lower inflammation levels, better metabolic health, and a reduced risk of age-related diseases such as neurodegenerative disorders. The study suggests that maintaining a healthy gut microbiome may play a crucial role in promoting healthy aging and longevity.

Unlocking the Secrets of the Human Gut Microbiota

This foundational review explores the enormous diversity of microbes in the human gut, including bacteria, viruses, fungi, and archaea. It emphasizes how this community isn’t just a passive passenger but actively influences digestion, nutrient absorption, immune system development, and even mental health through the gut-brain axis. The authors highlight that a balanced microbiome (eubiosis) supports barrier integrity and protects against pathogens, while dysbiosis can contribute to inflammatory diseases, metabolic disorders, and autoimmune conditions. The review also introduces techniques like 16S rRNA sequencing and metagenomics that allow researchers to map and understand microbial communities in unprecedented detail.

Human Gut Microbiota in Health and Disease: Unveiling the Relationship

This article provides an overview of how gut microbiota balance affects human health and disease. It emphasizes that not only the presence of specific microbes but their interactions, metabolic output, and community stability are critical. Dysbiosis—imbalances in microbial composition—has been linked to metabolic syndrome, inflammatory bowel disease (IBD), obesity, mental health disorders, and immune dysregulation. The paper also discusses the role of microbial metabolites such as short-chain fatty acids (SCFAs) and secondary bile acids in regulating immune and metabolic pathways. Understanding these relationships is crucial for designing dietary, probiotic, or prebiotic interventions that restore microbial balance.

The Gut Microbiome: A Core Regulator of Metabolism

This review focuses on the microbiome’s role in metabolic health, highlighting how gut microbes contribute to nutrient breakdown, energy harvest, and signalling to host tissues. Microbial metabolites, especially SCFAs, regulate glucose and lipid metabolism, maintain intestinal barrier integrity, and modulate inflammation. Dysbiosis can lead to metabolic dysfunction, contributing to obesity, type 2 diabetes, and cardiovascular disease. The authors also discuss how interventions like diet, fibre supplementation, and probiotics can influence microbiome composition and metabolic outcomes. This article underscores the microbiome as a potential therapeutic target for metabolic disorders.

Correlation Between Human Gut Microbiome and Diseases

This review explores connections between microbiome composition and a wide array of diseases, including autoimmune disorders, mental health conditions, metabolic disorders, and infections. It emphasizes that dysbiosis can either exacerbate disease or precede its onset, pointing to both diagnostic and therapeutic opportunities. The authors highlight specific taxa linked to disease states and discuss the mechanisms, such as increased intestinal permeability, altered immune responses, and microbial metabolite imbalance. Importantly, it emphasizes that restoring microbial balance via diet, prebiotics, probiotics, or even faecal microbiota transplantation could mitigate disease progression.

The Microbiome as a Major Function of the Gastrointestinal Tract and Its Role in Micronutrient Metabolism and Chronic Disease

This article focuses on the gut microbiome as an integral “organ” of the gastrointestinal tract. It discusses how microbes assist in digestion, vitamin synthesis, immune system maturation, and maintenance of the epithelial barrier. The review highlights that microbiome function—not just species composition—is key: the same species may act differently depending on context and diet. Dysbiosis can lead to barrier dysfunction, low-grade inflammation, and metabolic disturbances. This article reinforces the concept of the microbiome as a dynamic regulator of host health.

Microbiome 101: Studying, Analyzing, and Interpreting Gut Microbiome Data for Clinicians

This article explains the basics of the gut microbiome for doctors and health professionals. It describes what the microbiome is, how it can change over time, and how factors like diet, medicine, and lifestyle affect it. The authors outline common ways to study gut bacteria, such as different types of DNA testing, and warn that results can vary depending on the method used. They also point out that there is no single “normal” microbiome and that the science is still developing, but understanding it may help improve future medical care.

Neurotransmitter modulation by the gut microbiota

The paper reviews how bacteria in the gut can influence chemicals used by our brain—called neurotransmitters—like serotonin, dopamine, norepinephrine, and GABA. These gut microbes don’t just live quietly: they can make these chemicals themselves or change how our bodies produce or break them down. Animal studies show that these microbial effects may influence behaviour, mood, gut movement, and even diseases. Early human studies suggest similar possibilities, but the author says we still need lots more research to know exactly how these microbial-driven changes affect health in people, and whether we can use them for treatments.

Revised Estimates for the Number of Human and Bacteria Cells in the Body

Previous claims that bacteria in the human body outnumber human cells by about 10 to 1 are incorrect. The authors calculated that in a typical 70-kg adult, there are about 3.0×10¹³ human cells and about 3.8×10¹³ bacterial cells. That means the two are actually of a similar order of magnitude—not hugely different. Also, despite being similar in number, bacteria make up much less mass (only ~0.2 kg) compared with the human cells.

Dietary emulsifiers directly alter human microbiota composition and gene expression ex vivo potentiating intestinal inflammation

This research investigates how common food additives—specifically the emulsifiers carboxymethylcellulose (CMC) and polysorbate 80 (P80)—affect the gut microbiota. Using an advanced laboratory model that simulates the human gut, the study found that both emulsifiers can directly alter the composition and gene expression of the microbiota. These changes were associated with increased levels of pro-inflammatory markers, such as flagellin, suggesting that emulsifiers may promote intestinal inflammation. Additionally, when the altered microbiota was transferred to germ-free mice, it induced similar inflammatory responses, indicating that the emulsifiers' effects on the microbiota can influence host health.

Types and origins of bacterial membrane vesicles

This is a review of bacterial membrane vesicles (MVs). MVs are small, spherical structures released by bacteria into their surroundings. These vesicles play crucial roles in various biological processes, including communication between bacteria, interaction with host cells, and the transport of enzymes and toxins.The review categorizes MVs based on their origin and composition, discussing how different types are formed and their specific functions. It also explores the implications of MVs in health and disease, highlighting their potential as targets for therapeutic interventions.

The cellulose-degrading microbial community of the human gut varies according to the presence or absence of methanogens

In this study, the researchers looked at which gut bacteria can break down cellulose in people who either do or don’t produce methane (methanogens). They found that in methane-excreting individuals, cellulose-degrading bacteria were mostly from the Firmicutes group, while in non-methane excretors they were more from Bacteroidetes. These differences weren’t just in species, but also in what types of cellulose they could break down and how much hydrogen they produced during fermentation. Overall, the presence of methanogens seems to influence both the structure and function of cellulose-degrading bacteria in the human gut.

Our Mental Health Is Determined by an Intrinsic Interplay between the Central Nervous System, Enteric Nerves, and Gut Microbiota

The paper argues that our mental health is deeply shaped by interactions between the brain, the nervous system of the gut (the “enteric nervous system”), and the community of microbes living in our digestive tract (the gut microbiota). Signals travel bidirectionally between gut and brain — via nerves and chemical messengers — and microbiome‑driven changes can affect production or breakdown of neurotransmitters such as serotonin, dopamine, GABA and others. These interactions influence mood, cognition and are implicated in neuropsychiatric conditions (such as depression, schizophrenia or autism). Understanding this gut–brain–microbiota axis more fully could open the door to new “psychobiotic” therapies or lifestyle interventions that support mental health.

The athletic gut microbiota

This review argues that people who are regularly physically active — especially athletes — tend to have a gut microbiome that differs from sedentary individuals in ways likely beneficial to health and performance. The authors note that exercise (combined with the diet typical of active people) is associated with increased microbial diversity, a higher abundance of certain “health-promoting” bacteria, enhanced metabolic capacity of the microbiome, and greater production of beneficial microbial metabolites such as short‑chain fatty acids. These differences may support improved nutrient absorption, energy harvest, immune function, gut integrity and possibly better recovery and performance in sport.

The gut microbiota composition affects dietary polyphenols-mediated cognitive resilience in mice by modulating the bioavailability of phenolic acids

The study shows that the composition of gut microbiota has a direct effect on how beneficial dietary polyphenols (from a grape‑derived preparation, BDPP) are for memory, especially under conditions of sleep deprivation. When mice received BDPP, they normally maintained better memory after a period of sleep loss. But when their gut microbiota was disrupted by antibiotics, this memory‑protective effect vanished — and the levels in blood of polyphenol‑derived metabolites (phenolic acids) fell significantly. That suggests the gut microbes are needed to convert polyphenols into forms the body can absorb and use, and without that microbial conversion the cognitive benefit disappears.

Impact of outdoor nature-related activities on gut microbiota, fecal serotonin, and perceived stress in preschool children: the Play&Grow randomized controlled trial

This study had preschool children take part in a 10‑week nature‑based “Play&Grow” program and found that after the intervention their gut microbiota composition changed (including changes in the abundance of certain bacteria), their fecal serotonin levels remained stable (rather than dropping as in controls), and their reported stress — especially anger — decreased while prosocial behaviours improved.

Gut Microbiota and the Neuroendocrine System

The review describes how the community of microorganisms living in the gut — the gut microbiota — has a deep, two‑way interaction with the body’s major neuroendocrine system, especially the Hypothalamic–Pituitary–Adrenal axis (HPA axis), which governs stress responses and hormone signalling. The authors explain that signals from gut microbes — via metabolites, immune activity, gut‑barrier integrity, gut hormones, and nervous signalling — can influence HPA‑axis activity, while stress and neuroendocrine hormones in turn can shape the composition of the gut microbiota and gut barrier function. Through evidence from animal models (including germ‑free or antibiotic‑treated mice), probiotic/prebiotic interventions, and early life stress models, the paper argues that disruption of this gut–microbiota–neuroendocrine communication may contribute to disorders such as depression or stress‑related gut issues, and that modulating the gut microbiota may offer therapeutic promise.

Breaking down the barriers: the gut microbiome, intestinal permeability and stress-related psychiatric disorders

The paper argues that the collection of microbes in the gut plays a key role in maintaining the integrity of the intestinal barrier — and that when this barrier becomes “leaky,” microbes or their products may pass into the body, triggering low‑grade inflammation that can affect the brain. Such barrier disruption, often linked to stress or microbiome imbalance, may contribute to psychiatric or mood disorders by influencing immune, endocrine, and neural signalling between gut and brain.

The Two-Way Polyphenols-Microbiota Interactions and Their Effects on Obesity and Related Metabolic Diseases

The article reviews how dietary polyphenols — compounds found in fruits, vegetables, tea, wine and similar plant‑based foods — and the gut microbiota influence each other in a two‑way relationship. On one hand, gut microbes help break down polyphenols into more bioactive compounds, increasing their absorption and beneficial effects; on the other hand, polyphenols can shift the composition of the gut microbiota, promoting growth of helpful bacteria (like Bifidobacterium or Lactobacillus) and suppressing potentially harmful ones. This interaction may improve metabolism, reduce inflammation, and lower risks associated with obesity and other metabolic diseases.

Dynamics of Gut Microbiota Recovery after Antibiotic Exposure in Young and Old Mice (A Pilot Study)

This study looked at how the community of microbes in the gut recovers after a course of antibiotics. The authors found that antibiotics cause major shifts in which bacteria live in the gut, and that recovery of the original microbial community is often slow, incomplete, or variable between individuals. This shows that antibiotic treatment can have lasting effects on gut microbiota — which might influence digestion, immunity or other aspects of health long after the antibiotics are finished.

Relationships Between Vitamin D, Gut Microbiome, and Systemic Autoimmunity

The article reviews evidence linking low vitamin D levels, changes in gut microbiota, and increased risk of autoimmune diseases. It explains that vitamin D supports immune regulation and gut‑barrier integrity, and that vitamin‑D deficiency can alter gut bacterial communities and weaken the gut lining. This disruption may trigger imbalance in immune responses and contribute to diseases like inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, and lupus. As a result, the authors suggest that restoring healthy vitamin D levels — along with maintaining a balanced gut microbiome — might reduce autoimmune risk or severity.

THE GUT MICROBIOME