Alzheimer’s disease (AD) is the most prominent form of dementia in the USA, with 7·2 million Americans aged 65 years and older, living with AD in 2025. As the US population ages, there is a need for preventative measures to reduce the risk of AD. The apo E ϵ4 (ApoE4) allele is the greatest known genetic risk factor for AD, with heterozygous or homozygous ApoE4 carriers having increased likelihood of developing it. Due to abnormal lipid handling by ApoE4 carriers, precision nutrition may play a major role in delaying the onset of AD in these subjects, with n-3 fatty acids, lipids such as olive oil, vitamins C and E, Mediterranean, ketogenic and high-fibre diets showing promising but still limited evidence for ApoE4 carriers, as most of the current evidence comes from preclinical studies. Additionally, compared with non-carriers, ApoE4 carriers exhibit early gut dysbiosis, an imbalance in the gut microbiota that can disrupt normal digestive, metabolic and immune functions. The potential of probiotics and prebiotics to restore microbial balance and reduce dysbiosis in ApoE4 carriers has also been investigated. This review summarises evidence from observational human cohorts and clinical studies, animal models and in vitro mechanistic studies to examine emerging nutritional and gut-microbiome-based approaches to reduce AD risk in ApoE4 carriers. Future directions include the integration of precision nutrition with multi-omics approaches to allow for scalable and comprehensive analyses of ApoE–diet interactions and utilisation of larger human cohorts to determine the efficacy of nutritional and gut-based AD prevention strategies.

Colorectal cancer (CRC), a major global health burden, is the second leading cause of cancer deaths. This review examines the link between Helicobacter pylori infection and CRC, highlighting its role beyond gastric pathology. Affecting over half the world’s population, H. pylori is associated with increased CRC risk through direct and indirect mechanisms. Direct pathways include toxins like CagA and VacA, which drive inflammation, and hypergastrinaemia, which promotes colorectal cell proliferation. Indirectly, H. pylori induces immune dysregulation, shifts to immune-evasive coccoid forms, survives intracellularly, releases oncogenic vesicles, disrupts autophagy, alters non-coding RNAs by dysregulating their expression profiles and contributes to gut microbiota dysbiosis. Additionally, we discuss the potential of probiotic interventions to counteract H. pylori’s pathogenic effects by restoring gut microbial balance, reducing inflammation and modulating immunity by regulating cytokine and T-cell profiles. Future research should translate these molecular insights into clinical applications, including evaluating whether H. pylori eradication reduces CRC risk in high-risk populations and assessing the preventive potential of specific probiotic strains in controlled human trials.

Colorectal cancer (CRC) remains a leading cause of cancer-related morbidity and mortality worldwide. Emerging evidence suggests a dynamic mechanistic crosstalk between probiotics, non-coding RNAs (ncRNAs) and autophagy in CRC management. This review synthesizes the intricate interplay within this signalling axis to provide a comprehensive framework for precision medicine. Probiotics modulate the gut microenvironment and immune responses, while ncRNAs – specifically microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) – act as molecular rheostats regulating CRC progression and therapy resistance. Autophagy, a conserved cellular degradation process, plays a paradoxical role in tumour dynamics. This review elucidates the integrated signalling axis through which probiotics directly influence autophagic flux and indirectly reprogramme it through ncRNA-mediated pathways. Preclinical and clinical evidence highlight synergistic effects, such as probiotic-induced ncRNA shifts that fine-tune autophagy to induce apoptosis, curb tumour proliferation and break resistance mechanisms. By linking this microbial–epigenetic–autophagy crosstalk with current multimodal therapies, we propose an innovative framework for personalized oncology. This axis represents a critical new direction for future research, aiming to translate mechanistic insights into targeted therapeutic strategies for CRC.

Sarcopenia is a progressive skeletal muscle disorder characterized by the loss of muscle mass and strength. The concept of pro-anabolic modulators (including vitamin D, leucine, omega-3 fatty acids, and probiotics) as nutritional agents to counteract sarcopenia has been introduced as a promising strategy to restore anabolic balance in aging muscle. This systematic review aimed to synthesize recent evidence on the effectiveness of these compounds on muscle mass and physical performance. A total of 53 randomized controlled trials were included: 30 evaluated vitamin D, 8 leucine, 9 omega-3, and 6 probiotics. Across studies, although results for vitamin D were heterogeneous, daily supplementation suggested a more consistent potential for beneficial effects compared to bolus regimens, particularly when co-administered with other agents or physical exercise. Leucine demonstrated greater efficacy when combined with resistance training or other pro-anabolic agents. Most studies on omega-3 fatty acids reported improvements in muscle strength and functional outcomes, especially in long-duration interventions. Probiotics also showed promising results, with almost all studies reporting positive effects on muscle mass and strength, despite variability in strains and protocols. Given the low to very low certainty of evidence for most outcomes (except for physical performance, which reached moderate certainty), these results should be interpreted with caution, despite a general trend toward favorable outcomes. These findings suggest that combining pro-anabolic modulators (or pairing them with exercise or additional nutrients) may enhance their efficacy on muscle-related outcomes. Further research is warranted to define optimal protocols and to clarify the mechanisms underlying their potential synergistic effects.

The escalating global prevalence of antibiotic-resistant Helicobacter pylori strains has undermined conventional eradication therapies, heightening the burden of associated conditions such as gastritis, peptic ulcers and gastric malignancies. Emerging non-antibiotic alternatives, including natural and synthetic compounds, probiotics and vaccine candidates, offer potential solutions to combat these infections effectively. Natural and synthetic compounds provide promising anti-H. pylori effects, primarily through bacterial membrane disruption, urease inhibition, virulence gene suppression and biofilm prevention. in vitro and in vivo studies support the robust activity of natural agents, while synthetic counterparts demonstrate potent bactericidal and anti-adherence capabilities, though rigorous clinical validation is still required. Probiotic strains enhance eradication rates when combined with antibiotics, reduce treatment-related adverse effects, modulate gut microbiota and attenuate gastric inflammation and carcinogenesis. Vaccine development encompasses whole-cell, subunit and DNA platforms targeting key virulence factors, showing immunogenicity and protective efficacy in preclinical models, yet is limited by variable clinical translation and insufficient large-scale trials. Despite promising advancements, challenges persist, including inconsistent efficacy and a need for more rigorous human studies. Future efforts should emphasize combinatorial therapies, refined delivery systems, and thorough safety evaluations to integrate these strategies into clinical practice, fostering sustainable management of H. pylori in a post-antibiotic era.

This study systematically evaluates the effects of probiotic interventions on gut microbiota and clinical outcomes in diabetic patients to determine the optimal target population and conditions for effective use, with an emphasis on precision treatment. A comprehensive search was performed across PubMed, Web of Science, Cochrane Library, Embase, China National Knowledge Internet (CNKI), and Wanfang databases until April 2024. Randomized controlled trials (RCTs) assessing probiotics as adjunctive therapy for diabetes were included. The control group received standard care, and the intervention group received probiotics alongside standard care. Data were managed with Endnote and Excel, and analyses were conducted using Revman 5.3 and Stata 16. Twelve RCTs involving 1113 participants were included. Probiotics significantly increased fecal Lactobacillus (standardized mean difference (SMD) 1.42, P < 0.0001, I2 = 95 %) and Bifidobacterium levels (SMD 1.27, P < 0.0001, I2; = 90 %) and reduced fasting plasma glucose (SMD −0.35, P = 0.004). Subgroup analysis showed that shorter intervention durations (≤ 3 months) improved FPG, HbA1c, and Bifidobacterium levels, while younger patients (≤ 60 years) experienced the most significant improvements in Bifidobacterium levels. In conclusion, probiotics improve gut microbiota and clinical outcomes in diabetic patients, with intervention duration and patient age as key factors influencing treatment effectiveness.

Sarcopenia, the age-related decline in muscle mass and strength, is a contributor to frailty and reduced quality of life. Emerging evidence suggests an emerging role of the gut microbiome in modulating skeletal muscle through microbial species and metabolites, such as short-chain fatty acids (SCFAs), potentially influencing inflammation, nutrient absorption, and glucose and protein metabolism. This review considers the potential of probiotics, prebiotics, and synbiotics as interventions to mitigate sarcopenia based on animal and human studies, while providing a critique of present barriers that need to be addressed. Preclinical models, including germ-free mice and faecal microbiota transplantation, demonstrate that gut microbiota from healthy or young donors may enhance overall muscle health via reductions in inflammatory and muscle atrophy markers. Limited human studies show that probiotics such as Lactobacillus and Bifidobacterium could improve branched-chain amino acid (BCAA) bioavailability and potentially sarcopenia indices, although findings have been inconsistent. Particularly, challenges including inconsistent microbial assessments, lack of dietary control and interindividual variability due to diet, age, genetics, comorbidities and medications may hinder progress in this field. Delivery methods (e.g. capsules, fermented foods or fortified products) could further complicate efficacy through probiotic stability and dietary restrictions in older adults. Standardised protocols [e.g. Strengthening The Organisation and Reporting of Microbiome Studies (STORMS) checklist] and multi-omics approaches may be critical to address these limitations and identify microbial signatures linked to sarcopenia outcomes. While preclinical evidence highlights mechanistic pathways pertinent to amino acid metabolism, translating findings to humans requires rigorous experimental trials.

This study evaluated the effect of sweet whey fermented by Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772, an exopolysaccharide (EPS)-producing lactic acid bacterium (LAB), on the yield and quality of Requeson, a traditional Mexican fresh cheese, further supplemented with the probiotic strain Lactobacillus casei 431. Fermentation of the whey at 42°C for 48 hours resulted in the production of 1.126 ± 0.12 mgeq dextran/mL of EPS. The incorporation of this EPS-rich whey led to a marked (∼230%) increase in cheese yield and significantly enhanced textural properties, including greater hardness, cohesiveness and elasticity. Furthermore, L. casei 431 maintained viability above 107 cfu/g throughout 21 days of refrigerated storage (4°C), with no detectable microbial contamination. Although formulations containing EPS were slightly preferred in sensory evaluations, they exhibited improved stability and retained overall acceptable sensory quality. These results highlight the potential of EPS-producing LAB and probiotics to improve the technological, nutritional and functional attributes of fresh cheese, while contributing to the valorisation of dairy by-products.

Probiotics, defined as live microorganisms that confer health benefits when administrated in adequate amounts, including genera such as Lactobacillus, Bifidobacterium, Bacillus, Enterococcus, Escherichia, Streptococcus and the fungal strain Saccharomyces boulardii. Extensive research has demonstrated their beneficial effects, including vitamin synthesis, inhibition of pathogenic bacterial colonization, antimicrobial activity through bacteriocins and other bioactive compounds, and modulation of immune responses via secretory IgA antibodies. These attributes render probiotics promising candidates for managing antibiotic-associated colitis, post-surgical recovery and various diarrhoeal conditions. However, concerns regarding the safety of probiotics have emerged, with reports of Bacillus clausii sepsis in immunocompromised individuals and neonates, emphasizing the need for rigorous risk assessment. Similarly, postbiotic bioactive metableelites and components derived from probiotics have gained the attention of the scientific community all over the globe as potential alternatives to live probiotics. The International Scientific Association of Probiotics and Prebiotics defines postbiotics as ‘a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host’. Unlike probiotics, postbiotics do not require viability to exert their effects and include bioactive compounds such as short-chain fatty acids, peptides and exopolysaccharides. These molecules exhibit immunomodulatory, anti-inflammatory and antimicrobial properties, making them promising candidates for clinical applications, particularly in immunocompromised patients where live probiotics may pose risks. Despite their recognized benefits, both probiotics and postbiotics require further investigation to optimize their therapeutic potential while mitigating associated risks. This review critically evaluates the advantages, limitations and emerging applications of probiotics and postbiotics, emphasizing the necessity of rigorous scientific validation to ensure their safety and efficacy.

Interest in probiotics and prebiotics in sports nutrition is growing, but research on Jordanian athletes remains limited. While gut microbiota influences athletic performance, little is known about athletes’ understanding and use of probiotic- and prebiotic-rich foods in this region. This exploratory study investigates the knowledge, dietary habits, and correlations with gastrointestinal (GI) problems among Jordanian athletes to inform future research and interventions. The study provides insights into how awareness and consumption of gut-supportive foods can impact GI health, offering broader nutritional implications for global dietary strategies for athletes. A standardised questionnaire was administered to 324 athletes (ages 18–22) to assess knowledge, dietary practices, and GI symptoms. Descriptive statistics summarised the data, and chi-square tests examined associations among knowledge, diet, and GI symptoms (p < 0.05). Knowledge and diet were scored based on correct responses and reported intake of gut-supporting foods. Results showed that 55.9% of athletes were familiar with probiotics and 32.1% with prebiotics. The majority reported low consumption of probiotic- and prebiotic-rich foods, with 72.2% scoring low on diet intake. Although 60.5% seldom consumed fast food, overall intake of gut-supportive foods was limited. No statistically significant associations were found, but a weak positive trend between dietary habits and GI symptoms was observed, suggesting diet may have a modest influence on GI health. Living arrangements influenced both dietary choices and GI symptoms. This study highlights the need for targeted nutrition education to improve awareness and intake of probiotics and prebiotics, potentially supporting GI health and enhancing athletic performance.

This study aims to assess the therapeutic effects of probiotic oral therapy in paediatric patients with anorexia nervosa (AN) and to investigate its impact on intestinal flora composition, brain–gut peptide levels and overall clinical outcomes. A retrospective study was conducted involving 100 children diagnosed with AN at Xingtang County People’s Hospital between January 2023 and June 2024. Patients were divided into two groups: a control group (n 50) receiving zinc gluconate oral solution alone and an observation group (n 50) receiving zinc gluconate plus probiotics. Outcome measures included intestinal flora analysis, brain–gut peptide levels (somatostatin (SS) and nitric oxide (NO)), clinical efficacy, serum trace element levels (Ca, Zn and Fe) and prognosis, including recurrence rates 6 months post-treatment. Baseline characteristics were similar between the two groups (P > 0·05). After treatment, the observation group showed significantly higher levels of Bifidobacterium and Lactobacillus and lower levels of Enterobacter compared with the control group (P < 0·05). Additionally, the observation group had lower levels of SS and NO (P < 0·05), indicating improved brain–gut communication. Clinical efficacy was significantly higher in the observation group (P < 0·05), with improved serum trace element levels (P < 0·05 for Ca, Zn and Fe). Furthermore, the recurrence rate 6 months post-treatment was significantly lower in the observation group compared with the control group (P < 0·05). Probiotic supplementation in children with AN effectively modulates intestinal flora, improves brain–gut peptide levels and enhances clinical outcomes.

To clarify the effects of kefir in critical periods of development in adult diseases, we study the effects of kefir intake during early life on gut microbiota and prevention of colorectal carcinogenesis in adulthood. Lactating Wistar rats were divided into three groups: control (C), kefir lactation (KL), and kefir puberty (KP) groups. The C and KP groups received 1 mL of water/day; KL dams received kefir milk daily (108 CFU/mL) during lactation. After weaning (postnatal day 21), KP pups received kefir treatment until 60 days. At 67 days old, colorectal carcinogenesis was induced through intraperitoneal injection of 1, 2-dimethylhydrazine. The gut microbiota composition were analyzed by 16S rRNA gene sequencing and DESeq2 (differential abundance method), revealing significant differences in bacterial abundances between the kefir consumption periods. Maternal kefir intake strong anticancer power, suppressed tumors in adult offspring and reduced the relative risk of offspring tumor development. The gut microbiota in cecal samples of the KL group was enriched with Lactobacillus, Romboutsia, and Blautia. In contrast, control animals were enriched with Acinetobacter. The administration of kefir during critical periods of development, with emphasis on lactation, affected the gut microbial community structure to promote host benefits. Pearson analysis indicated positive correlation between tumor number with IL-1 levels. Therefore, the probiotic fermented food intake in early life may be effective as chemopreventive potential against colon tumor development, especially in lactation period.

Oral supplementation with probiotics, prebiotics, and synbiotics is a novel potential complementary therapy for addressing overweight and obesity through gut microbiota modulation. This systematic review provides a comprehensive summary of the existing evidence to guide future research. Literature searches were conducted in four databases to identify human trials published until May 2024 that examined the impact of probiotic, prebiotic, or synbiotic interventions on faecal microbiota composition changes in overweight and obese participants from Latin American and Caribbean populations (LACPs). Of the 13,090 identified records, five randomised controlled trials (RCTs) from Brazil, Mexico, and Chile met the inclusion criteria for this review. The included RCTs evaluated different forms of therapies over short-term interventions (6 or 8 weeks), with sample sizes ranging from 21 to 39 participants across the studies. Variations in the reported outcomes were observed due to differences in supplement formulation, dosage, population characteristics, and methodological heterogeneity. The findings indicate that the available data are inadequate to establish definitive conclusions regarding the impact of biotic treatments on gut microbiota profiles in LACP. Further research with larger sample sizes and precise microbiota analysis is required to elucidate the implications of dietary interventions on gut microbiota in obesity and related disorders.

Increased intestinal leakiness and associated systemic inflammation are potential contributors to osteoarthritis (OA) and postural imbalance in the geriatric population. To date, no successful treatment to correct postural imbalance in OA is known. We aimed to explore the effects of a multistrain probiotic upon postural imbalance in OA-affected patients. In this randomised, double-blind trial with a placebo group, 147 patients suffering from knee OA (age span = 64–75 years) were divided into placebo (n 75) and probiotics (n 72) study groups. Vivomix 112 billion, multistrain probiotic was given once a day for 12 weeks. The outcomes of study variables were determined first at baseline and later after 12 weeks of intervention. These were Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), knee flexion range of motion (ROM), pain intensity by visual analogue scale, handgrip strength (HGS), gait speed and balance control assessed in standing, semi-tandem and tandem stances. We determined plasma zonulin to determine intestinal leak along with c-reactive protein and 8-isoprostanes levels. A total of 136 OA patients taking placebo (n 71) and probiotics (n 65) were analysed. The probiotics group exhibited a reduction in pain intensity, disease severity and WOMAC scores along with improvement in balance scores, HGS and walking speed (P < 0·05 for all), no change in ROM, resting pain and 8-isoprostanes levels. The correlation analysis revealed a robust association of balance scores with plasma markers of intestinal leakiness and inflammation in probiotics but not in the placebo group. Probiotics reduce postural imbalance in OA patients partly due to a reduction in intestinal leakiness.

This study examined the efficacy of a probiotic in reducing depressive symptom severity in people with subthreshold depression. In a double-blind, randomised, placebo-controlled trial, a probiotic (1 × 10^9 live cells per strain: Limosilactobacillus fermentum LF16 (DSM26956), Lacticaseibacillus rhamnosus LR06 (DSM21981), Lactiplantibacillus plantarum LP01 (LMG P-21021) and Bifidobacterium longum 04 (DSM23233)) or placebo was taken daily for 12 weeks. Data were collected at baseline, 6 and 12 weeks including psychological symptom severity (Beck Depression Inventory, BDI; Patient Health Questionnaire, PHQ; Hospital Anxiety Depression Scale, HADS; and Depression Anxiety and Stress Scale, DASS). Biomarkers of glycaemia, inflammation (high-sensitivity C-reactive protein, hs-CRP), antioxidant status (total glutathione (GSH)) and stress (cortisol awakening response, CAR) were also measured. Thirty-nine participants (nineteen probiotic; twenty placebo) were enrolled. There were no significant between-group differences in the examined psychological symptom severity scores, despite certain significant within-group changes observed in both groups from baseline to 6 and/or 12 weeks of follow-up. Regarding biomarkers, the probiotic group showed reduced hs-CRP (–1520; 95 % CI –273·7, −2766·2 ng/dl) and CAR (–0·28; 95 % CI −0·05, −0·51 μg/dl) at 12 weeks, but increased total GSH (3·9; 95 % CI 0·1, 7·5 ng/dl) at 6 weeks, compared with the placebo. The current study reported favourable decreases in depressive symptoms in both groups. Although the within-group changes observed in the probiotic group were supported by favourable inflammatory, antioxidant status and stress biomarker changes compared with the placebo, further research is required to shed more light on the role of gut microbiota modulation on emotional regulation.

Depression is the leading cause of disability worldwide(1). The microbiota-gut-brain axis may play a role in the aetiology of depression, and probiotics show promise for improving mood and depressive state(2). Further evidence is required to support mechanisms and in high-risk populations, such as those with sub-threshold depression (which may be 2-3 times more prevalent than diagnosed depression)(3). The aims were to assess the efficacy of a probiotic compared with placebo in reducing the severity of depressive symptoms in participants with subthreshold depression, and to investigate potential mechanistic markers of inflammatory, antioxidant status and stress response. A double-blind, randomised, placebo-controlled trial was conducted in participants meeting diagnosis of subthreshold depression (DSM-5); aged 18-65 years; ≥18.5 kg/m2 body mass index; not taking antidepressants, centrally acting medications, probiotics nor antibiotics for at least 6 weeks. The probiotic (4 × 109 AFU/CFU, 2.5 g freeze-dried powder containing Lactobacillus fermentum LF16 (DSM26956), L. rhamnosus LR06 (DSM21981), L. plantarum LP01 (LMG P-21021), Bifidobacterium longum BL04 (DSM 23233)) or placebo was taken daily for 3-months. Data was collected at 3 study visits (pre-, mid- (6 weeks), post-intervention). Self-reported questionnaires measured psychological symptoms (Beck Depression Inventory, BDI; Hospital Anxiety Depression Scale, HADS) and quality of life. Blood and salivary samples were collected for biomarkers including cortisol awakening response (CAR). General linear models examined within-group and between-group differences across all time points. Thirty-nine participants completed the study (n = 19 probiotic; n = 20 placebo) using intention-to-treat analysis. The probiotic group decreased in BDI score by −6.5 (95% CI −12.3; −0.7) and −7.6 (95% CI −13.4; −1.8) at 6 and 12 weeks, respectively. The HADS-A score decreased in the probiotic group by −2.8 (95% CI −5.2; −0.4) and −2.7 (95% CI −5.1; −0.3) at 6 and 12, respectively. The HADS-D score decreased in the probiotic group by −3.0 (95% CI −5.4; −0.7) and −2.5 (−4.9; −0.2) at 6 and 12 weeks of intervention, respectively. No between group differences were found. There were no changes in perceived stress or quality of life scores. The probiotic group had reduced hs-CRP levels (7286.2 ± 1205.8 ng/dL vs. 5976.4 ± 1408.3; P = 0.003) and increased total glutathione (14.2 ± 8.9 ng/dL vs. 9.3 ± 4.7; P = 0.049) compared to placebo, post intervention. Lower levels of CAR were found in the probiotic compared to placebo (−0.04 ± 0.17 μg/dL vs. 0.16 ± 0.25; P = 0.009). A significant reduction in depressive symptoms and anxiety was observed within the probiotic group only. These results were supported by improvements observed in biomarkers, suggesting probiotics may improve psychological wellbeing in adults experiencing sub-threshold depression, by potential pathways involved in central nervous system homeostasis and inflammation. Future analyses are required to understand changes within the intestinal microbiota and to clarify how their metabolites facilitate emotional processing.