The gastrointestinal tract is home to trillions of diverse microorganisms collectively known as the gut microbiota, which play a pivotal role in breaking down undigested foods, such as dietary fibers. Through the fermentation of these food components, short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are produced, offering numerous health benefits to the host. The production and absorption of these SCFAs occur through various mechanisms within the human intestine, contingent upon the types of dietary fibers reaching the gut and the specific microorganisms engaged in fermentation. Medical literature extensively documents the supplementation of SCFAs, particularly butyrate, in the treatment of gastrointestinal, metabolic, cardiovascular, and gut-brain-related disorders. This review seeks to provide an overview of the dynamics involved in the production and absorption of acetate, propionate, and butyrate within the human gut. Additionally, it will focus on the pivotal roles these SCFAs play in promoting gastrointestinal and metabolic health, as well as their current therapeutic implications.

Background: Butyrate has shown anti‐inflammatory and regenerative properties, providing symptomatic relief when orally supplemented in patients suffering from various colonic diseases. We investigated the effect of a colonic‐delivery formulation of butyrate on the fecal microbiota of patients with inflammatory bowel diseases (IBDs).Methods: In this double‐blind, placebo‐controlled, pilot study, 49 IBD patients (n = 19 Crohn's disease, CD and n = 30 ulcerative colitis, UC) were randomized to oral administration of microencapsulated‐sodium‐butyrate (BLM) or placebo for 2 months, in addition to conventional therapy. Eighteen healthy volunteers (HVs) were recruited to provide a healthy microbiota model of the local people. Fecal microbiota from stool samples was assessed by 16S sequencing. Clinical disease activity and quality of life (QoL) were evaluated before and after treatment.Key Results: At baseline, HVs showed a different microbiota composition compared with IBD patients. Sodium‐butyrate altered the gut microbiota of IBD patients by increasing bacteria able to produce SCFA in UC patients (Lachnospiraceae spp.) and the butyrogenic colonic bacteria in CD patients (Butyricicoccus). In UC patients, QoL was positively affected by treatment.Conclusions and Inferences: Sodium‐butyrate supplementation increases the growth of bacteria able to produce SCFA with potentially anti‐inflammatory action. The clinical impact of this finding requires further investigation.

The gastrointestinal tract is colonized by trillions of different microorganisms, named the gut microbiota, which is key to degrade undigested food such as dietary fibers. The fermentation of these food components leads to the production of short-chain fatty acids (SCFA) acetate, propionate, and butyrate, which exploit several beneficial roles for the host’s health. Their production and absorption happen in different ways in the human intestine and depend on the type of dietary fiber reaching the gut and the microorganisms involved in the fermentation. The supplementation of SCFAs, mostly butyrate, in treating gastrointestinal, metabolic, cardiovascular, and gut-brain-related diseases has been reported in the medical literature. This review aims to give an overview of the production and absorption dynamics of acetate, propionate, and butyrate in the human gut, with a final focus on the role played by these SCFAs on gastrointestinal and metabolic health and the present therapeutic implications.

Propionate is a short-chain fatty acid (SCFA) produced by gut microbiota through the fermentation of dietary fibers. Among the SCFAs, butyrate stands out and has been extensively studied for its beneficial effects; however, propionate has received less attention despite its relevant roles in immune modulation, metabolism, and mucosal homeostasis. This narrative review focuses on propionate’s effects on metabolism, inflammation, microbiota, and gastrointestinal diseases. Propionate acts as a signalling molecule through FFAR2/FFAR3 receptors and modulates immunity, energy metabolism, and gut–brain communication. It has beneficial effects in metabolic disorders, inflammatory bowel disease (IBD), and alcohol-related liver disease (ALD). However, excessive accumulation is linked to neurotoxicity, autism spectrum disorder (ASD), and mitochondrial dysfunction. Its effects are dose-dependent and tissue-specific, with both protective and harmful potentials depending on the context. Propionate use requires a personalized approach, considering the pathological context, host microbiota composition, and appropriate dosage to avoid adverse effects.

The attention on microbiome research and its translation to application deployment is escalating along with diffused hype. There is real excitement in this new science, leveraging the growing potential of advances in molecular biology and sequencing techniques. Yet, despite the substantial efforts provided by the scientific communities, the true significance of research achievements requires coordinated and constructive actions across interdisciplinary fields. Individual researchers, universities, small and large companies, venture capitalists, and governments play a fundamental role in fostering collaboration and promoting knowledge that will benefit each other and sustain global prosperity. Making meaningful connections across different fields and getting a new perspective on how technological developments interrelate are the main drivers for creativity and progress.

Patients with triple-negative breast cancer (TNBC) achieving a pathological complete response (pCR) after neoadjuvant chemotherapy have a better event-free survival. The role of gut microbiome in early TNBC is underexplored. Microbiome was analyzed by 16SrRNA sequencing. Twenty-five patients with TNBC treated with neoadjuvant anthracycline/taxane-based chemotherapy were included. Fifty-six percent achieved a pCR. Fecal samples were collected before (t0), at 1 (t1), and 8 weeks (t2) from chemotherapy. Overall, 68/75 samples (90.7%) were suitable for microbiome analysis. At t0, pCR group showed a significantly higher α-diversity as compared with no-pCR, (P = .049). The PERMANOVA test on β-diversity highlighted a significant difference in terms of BMI (P = 0.039). Among patients with available matched samples at t0 and t1, no significant variation in microbiome composition was reported over time. Fecal microbiome analysis in early TNBC is feasible and deserves further investigation in order to unravel its complex correlation with immunity and cancer.