Search Results (6,520)

Background/Objectives: Obstructive sleep apnea (OSA) is often accompanied by metabolic syndrome (MetS), forming a high-risk phenotype with elevated cardiometabolic burden. The contribution of lifestyle behaviors—particularly eating mechanics and psychological eating cues—to disease severity remains unclear. This study examined independent associations of dietary behaviors and physical activity (PA) with OSA severity, sleep quality, and metabolic health. Methods: Forty-four OSA patients (mean age 38.3 ± 9.1 years; 89% male) underwent attended polysomnography, dual-energy X-ray absorptiometry, and metabolic profiling. Validated questionnaires assessed dietary behaviors, PA, and sleep quality. Hierarchical logistic regression identified predictors of MetS, severe OSA, and poor sleep quality. Results: The prevalence of MetS was 45%. Compared with those with OSA alone, participants with MetS demonstrated significantly greater central adiposity and more severe nocturnal hypoxemia, despite similar apnea–hypopnea indexes. In multivariable models, MetS was independently associated with higher body mass index (adjusted odds ratio [aOR] = 1.64; p = 0.008) and reward eating (aOR = 3.34; p = 0.041), whereas higher total PA was associated with reduced odds (aOR = 0.96; p = 0.026). Poor subjective sleep quality was significantly associated with younger age (aOR = 0.91; p = 0.037). For severe OSA, slow chewing was associated with significantly reduced odds (aOR = 0.24; p = 0.038), while emotional eating was associated with increased odds (aOR = 2.40; p = 0.048). Conclusions: This hypothesis-generating study identifies a high-risk OSA phenotype marked by metabolic dysfunction and hypoxemia. Eating speed (a proxy for mindful eating), emotional and reward-driven eating, and PA independently shape metabolic and respiratory outcomes. These findings support incorporating behavioral nutrition into multidisciplinary OSA management. Full article

Background: Ageing profoundly alters endocrine regulation and nutrient metabolism, predisposing older adults to thyroid dysfunction. Iodine, an essential micronutrient, lies at the center of this vulnerability due to its narrow physiological range and multiple interactions with nutrition, medications, renal function, and, presumably, gut microbiota. Objective: This narrative review integrates evidence on how ageing modifies iodine–thyroid homeostasis, emphasizing the roles of dietary intake, pharmacologic exposures, microbiota composition, and age-related metabolic alterations that influence iodine handling and thyroid hormone economy. Main Findings: Physiological ageing reduces renal iodine clearance, thyroidal reserve, and peripheral hormone conversion, while chronic inflammation and multimorbidity increase susceptibility to both iodine deficiency and excess. Polypharmacy, including amiodarone, lithium, and proton pump inhibitors, further destabilizes thyroid function. Age-related dysbiosis may impair micronutrient absorption and immune tolerance, linking gut ecology to thyroid autoimmunity. The gut microbiota may influence thyroid function through immune and metabolic pathways, although current evidence in older adults remains limited. Together, these factors shift the balance between iodine intake and utilization, heightening the risk of subclinical or overt hypothyroidism in older adults. Conclusions: Overall, variations in iodine intake emerge as one of the main determinants of thyroid dysfunction in ageing with nutritional, pharmacologic, and other modifiers primarily influencing iodine-related thyroid vulnerability. The adoption of age-adjusted thyroid reference ranges and preventive monitoring can reduce overtreatment and improve metabolic resilience in later life. Full article

Poultry production faces considerable challenges in terms of feed costs and sustainability, particularly regarding conventional protein sources such as fish meal (FM). Insect-based proteins, such as housefly larvae (HL) meal, offer sustainable alternatives. Therefore, this study aimed to investigate the effects of HL on growth, gut health, metabolizable energy, and gut microbiota of broilers to clarify the availability of HL meal for broiler diet. Experiment 1 was performed to investigate the effects of replacing FM with HL on growth performance, intestinal morphology, cecal short-chain fatty acids, and gut microbiota composition and diversity in male broilers. Experiment 2 was performed to assess the digestibility of broiler diets containing HL. HL addition effectively maintained growth and improved intestinal morphology. Blood analysis revealed that HL addition reduced TNF-α levels and improved protein utilization. Additionally, HL substitution induced significant changes in the gut microbiota community and metabolic pathways. In conclusion, HL are a viable alternative to FM with adequate energy content and beneficial effects on gut health, supporting their use as a sustainable protein source. Full article

Background and Objectives: Intermittent fasting (IF) has emerged as a nutritional strategy capable of modulating circadian alignment, metabolic efficiency, and neuroendocrine regulation in individuals with obesity. Among the neurobiological mediators potentially involved, Orexin-A—a hypothalamic neuropeptide regulating arousal, appetite, and energy balance—may represent a key link between fasting patterns and metabolic homeostasis. This study aimed to evaluate the long-term metabolic and neuroendocrine effects of two intermittent fasting protocols, time-restricted feeding (16:8) and alternate-day fasting (5:2), compared with a hypocaloric Mediterranean diet used as a reference condition. Materials and Methods: Thirty adults with obesity (aged 20–40 years) were allocated to one of three dietary interventions—low-calorie Mediterranean diet, IF 16:8, or IF 5:2—based on habitual dietary patterns and followed prospectively for 12 months. Anthropometric parameters, metabolic indices, inflammatory markers (CRP, TNF-α, IL-6, IL-10), and circulating Orexin-A concentrations were assessed at baseline and at three-month intervals (T0–T3). Results: Both intermittent fasting protocols induced more rapid improvements in body mass index, adiposity, lipid profile, fasting glucose, and inflammatory markers compared with the Mediterranean diet. Among the IF strategies, the 16:8 regimen showed the most consistent and physiologically coherent pattern of adaptation, characterized by a progressive and sustained increase in Orexin-A levels. This response was strongly associated with enhanced metabolic flexibility, reduced systemic inflammation, and improved energy regulation over time. In contrast, the 5:2 protocol produced more variable metabolic and neuroendocrine responses, likely due to alternating cycles of marked caloric restriction and compensatory intake. Conclusions: Intermittent fasting, particularly the 16:8 time-restricted feeding protocol, appears to be an effective and sustainable chrononutritional strategy for obesity management. By reinforcing circadian organization, improving inflammatory balance, and activating orexinergic pathways, the 16:8 model emerges as a promising intervention to address key metabolic and neuroendocrine dysfunctions associated with obesity. Full article

Diet plays a central role in shaping the composition and metabolic activity of the oral microbiota, thereby influencing both oral and systemic health. Disturbances in this delicate host–microbe balance, triggered by dietary factors, smoking, poor oral hygiene, or antibiotic use, can lead to microbial dysbiosis and increase the risk of oral diseases such as periodontitis, as well as chronic systemic disorders including diabetes, cardiovascular disease, Alzheimer’s disease, and certain cancers. Among dietary contaminants, exposure to toxic heavy metals such as cadmium (Cd), lead (Pb), mercury (Hg), nickel (Ni), and arsenic (As) represents an underrecognized modifier of the oral microbial ecosystem. Even at low concentrations, these elements can disrupt microbial diversity, promote inflammation, and impair metabolic homeostasis. Saliva has recently emerged as a promising, non-invasive biofluid for monitoring nutritional status and early metabolic alterations induced by diet and environmental exposures. Salivary biomarkers, including metabolites, trace elements, and microbial signatures, offer potential for assessing the combined effects of diet, microbiota, and toxicant exposure. This review synthesizes current evidence on how diet influences the oral microbiota and modulates susceptibility to heavy metal toxicity. It also examines the potential of salivary biomarkers as integrative indicators of nutritional status and metabolic health, highlights methodological challenges limiting their validation, and outlines future research directions for developing saliva-based tools in personalized nutrition and precision health. Full article

Background: Protein–energy wasting (PEW) is a major predictor of morbidity and mortality in patients with chronic kidney disease (CKD), even before the initiation of dialysis. Its multifactorial pathogenesis includes reduced dietary intake, chronic inflammation, metabolic acidosis, hormonal disturbances, and dysbiosis of the gut microbiota. Early recognition and targeted management are crucial for preventing muscle loss, functional decline, and adverse outcomes. Methods: This narrative review summarises and integrates current evidence from the literature on nutritional and metabolic interventions to prevent and treat protein–energy wasting in patients with nondialysis chronic kidney disease. Relevant clinical trials, meta-analyses, and experimental studies published up to date were evaluated, focusing on dietary strategies, metabolic modulation, physical exercise, and gut microbiome-targeted therapies. Results: Adequate energy and protein intake remain the cornerstone of PEW management, based on available clinical and observational evidence. Individualised diets emphasising high-quality and plant-based proteins, oral nutritional supplements, and ketoanalogues can attenuate muscle wasting. Correction of metabolic acidosis and inflammation enhances protein anabolism and nitrogen balance. Physical exercise acts synergistically with dietary interventions to preserve muscle mass and function. Novel approaches—such as modulating the gut–kidney axis with pre-, pro-, and postbiotics or supplementing with short-chain fatty acids—show promise in improving metabolic and inflammatory profiles. Conclusions: The management of PEW in nondialysis CKD requires a personalised approach that integrates nutrition, physical activity, metabolic correction and microbiome modulation. Early, coordinated intervention may help to slow the progression of CKD and improve patient survival and quality of life. Full article

Background/Objectives: Lithium (Li), silicon (Si), and boron (B) are proposed nutritional trace elements with potential roles in metabolic, neurobiological, endocrine, inflammatory, and bone-related processes. This review provides a critical synthesis of data on Li–Si–B, emphasizing (i) physiological and mechanistic pathways, (ii) human clinical relevance, (iii) shared biological domains, and (iv) safety considerations. Methods: A narrative review was conducted across PubMed, Scopus, and Web of Science from inception to January 2025. Predefined search strings targeted dietary, environmental, and supplemental exposures of lithium, silicon, or boron in relation to metabolism, endocrine function, neurobiology, inflammation, bone health, and the gut microbiome. Inclusion criteria required peer-reviewed studies in English. Data extraction followed a structured template, and evidence was stratified into human, animal, cellular, and ecological tiers. Methodological limitations were critically appraised. Results: Li, Si, and B influence overlapping molecular pathways including oxidative stress modulation, mitochondrial stability, inflammatory signaling, endocrine regulation, and epithelial/gut barrier function. Human evidence remains limited: Li is supported primarily by small trials; Si by bone-related observational studies and biomarker-oriented interventions; and B by metabolic, inflammatory, and cognitive studies of modest sample size. Convergence across elements appears in redox control, barrier function, and neuroimmune interactions, but mechanistic synergism remains hypothetical. Conclusions: Although Li–Si–B display compelling mechanistic potential, current human data are insufficient to justify dietary recommendations or supplementation. Considerable research gaps—including exposure assessment, dose–response characterization, toxicity thresholds, and controlled human trials—must be addressed before translation into public health policy. Full article

Background/Objectives: Energy availability (EA), defined as the dietary energy remaining after exercise energy expenditure (EEE), is a central determinant of both health and performance in athletes. Chronic insufficient EA leads to low energy availability (LEA), which is an underlying mechanism of Relative Energy Deficiency in Sport (REDs). This narrative review critically explores the conceptual evolution of EA and LEA, summarizes current physiological evidence, and discusses methodological and practical challenges in their assessment and application in free-living athletes. Methods: Evidence from experimental and observational studies was reviewed to describe the hormonal, metabolic, and performance outcomes associated with LEA. Screening tools, including the Low Energy Availability in Females Questionnaire (LEAF-Q) and the Low Energy Availability in Males Questionnaire (LEAM-Q), were also evaluated for their validity and applicability in different sports contexts. Results: LEA is associated with alterations in thyroid and reproductive hormones, which, in turn, contribute to reduced resting metabolic rate, lower bone mineral density, and delayed recovery. While screening questionnaires can help identify athletes at risk, their accuracy varies by sport and individual characteristics. Incorporating hormonal and metabolic biomarkers provides a more direct and sensitive method for detecting physiological stress. Measuring dietary intake, EEE, endocrine balance and body composition in real-world settings remains a major methodological challenge. Combining hormonal, metabolic, and behavioral indicators may improve the identification of athletes experiencing LEA. Conclusions: EA plays a central role in the interaction between nutrition, exercise, and athlete health, but methodological limitations in its assessment may compromise accurate diagnosis. Improving measurement techniques and adopting integrated monitoring strategies are essential to improve early detection, guide individualized nutrition, and prevent RED-related health and performance impairments. Full article

Background: Calcium (Ca) and magnesium (Mg) are essential micronutrients integral to metabolic processes and cardiovascular health. Emerging evidence suggests that the dietary Ca:Mg ratio may influence chronic disease risk, yet variability in this ratio across diverse demographic groups and its relationship to body composition and vitamin D status remain unclear. Methods: Dietary intakes of Ca and Mg were assessed using validated Food Frequency Questionnaires (FFQs) and body composition was quantified via Dual-energy X-ray Absorptiometry (DXA) scans. Relationships between dietary Ca:Mg ratios and demographics, body composition parameters (lean and fat mass), and vitamin D and parathyroid hormone (PTH) levels were examined statistically using SPSS ver. 29.0 and R ver. 4.5.1 (2025) employing Kruskal–Wallis, regression, and moderated mediation analyses. Results: We examined 155 healthy adults with a mean age of 36.6 ± 12.5 years. Only 16.8% had adequate intakes of Mg compared with 45.8% who had adequate dietary Ca intakes. Significant differences in the Ca:Mg ratio were observed across racial groups (p = 0.023) and age groups (p = 0.017). South Asian Indians exhibited the highest median Ca:Mg ratio (4.83), whereas African Americans exhibited the lowest (2.67). Interestingly, our moderated mediation analysis indicated that African Americans were the most sensitive to the impact of PTH changes on the balance of Ca:Mg (indirect effect = −0.762, 95% CI [−1.298, −0.234]), indicating that even slight shifts in their Ca:Mg balances cause significant elevation in the PTH, which, in turn, leads to lowering of their vitamin D levels. Young adults (ages 18–29) had the highest median Ca:Mg ratio (4.73). No statistically significant differences were detected based on Gender (p = 0.425 and BMI (p = 0.744) on Ca:Mg ratios. Additionally, dietary Ca:Mg ratios were positively associated with sPTH in males (r = 0.203, p < 0.05), but not with body composition. Conclusion: Important variations in dietary Ca:Mg ratios exist across racial and age demographics, notably among young adults, and specific ethnic groups exhibited elevated ratios. Tailored nutritional interventions may be necessary for these populations to optimize Ca:Mg balance and support metabolic and cardiovascular health outcomes in these populations. Full article

This study aimed to assess the variation, genetic architecture, and genome-enabled prediction of traits with nutritional and health relevance in 156 pea (Pisum sativum L.) accessions of diverse geographic origins. The traits included the total phenolic compounds (TPCs), two saponins (Ssβg, Ss1), sucrose, three raffinose-family oligosaccharides (RFOs), and the in vitro antioxidant activity (AA). An analysis of variance revealed significant effects of regional germplasm pools for all traits. Accessions from West Asia showed the highest TPC and AA levels, while those from the East Balkans and the UK displayed the lowest values. High saponin and RFO concentrations characterized accessions from Germany and the UK. Correlation and PCA analyses highlighted strong associations within compound classes and an overall negative relationship between TPCs/AA and saponins/RFOs. The accessions were clustered into seven metabolically distinct groups, partially reflecting their geographic origin. The linkage disequilibrium decayed rapidly (average of 4.7 kb). A GWAS based on 10,249 SNP markers identified 37 significant SNPs, 35 within annotated genes, associated with the metabolites, indicating a polygenic genetic architecture. Genomic prediction models showed a moderately high predictive ability (>0.40) for all traits except the raffinose content. Our findings can support line selection and the identification of genetic resources with a desired level of secondary metabolites. Full article

Aging is accompanied by progressive gastrointestinal structural and functional decline, increased intestinal permeability, dysbiosis, and impaired mucosal immunity, collectively elevating susceptibility to infections, chronic inflammation, and multimorbidity. These age-related changes are further exacerbated by polypharmacy, metabolic disorders, and lifestyle factors, positioning the gastrointestinal tract as a central driver of systemic physiological decline. Gut-centered interventions have emerged as critical strategies to mitigate these vulnerabilities and support healthy aging. Dietary modulation, prebiotic and probiotic supplementation, and microbiota-targeted approaches have demonstrated efficacy in improving gut microbial diversity, enhancing short-chain fatty acid production, restoring epithelial integrity, and modulating immune signaling in older adults. Beyond nutritional strategies, non-nutritional interventions such as molecular hydrogen and medical ozone offer complementary mechanisms by selectively neutralizing reactive oxygen species, reducing pro-inflammatory signaling, modulating gut microbiota, and promoting mucosal repair. Hydrogen-based therapies, administered via hydrogen-rich water or inhalation, confer antioxidant, anti-inflammatory, and cytoprotective effects, while ozone therapy exhibits broad-spectrum antimicrobial activity, enhances tissue oxygenation, and stimulates epithelial and vascular repair. Economic considerations further differentiate these modalities, with hydrogenated water positioned as a premium wellness product and ozonated water representing a cost-effective, scalable option for geriatric gastrointestinal care. Although preclinical and early clinical studies are promising, evidence in older adults remains limited, emphasizing the need for well-designed, age-specific trials to establish safety, dosing, and efficacy. Integrating dietary, microbiota-targeted, and emerging non-nutritional gut-centered interventions offers a multimodal framework to preserve gut integrity, immune competence, and functional health, potentially mitigating age-related decline and supporting overall health span in older populations. Full article

Background/Objectives: Prebiotics, which are non-digestible compounds that selectively modulate gut microbiota, are recognized for their potential to promote host health. Although their bifidogenic effect is well documented, a systematic synthesis of how this microbial modulation translates into clinical gastrointestinal (GI) and metabolic outcomes across diverse populations is needed. This review aims to integrate mechanistic insights with clinical evidence to elucidate the pathway from prebiotic structures to tangible health benefits. Methods: This comprehensive narrative review details the structural properties of major prebiotics (e.g., inulin, FOS, and GOS) that govern their fermentation and the production of short-chain fatty acids (SCFAs). To evaluate clinical efficacy, an analysis of 22 randomized controlled trials from the past decade was conducted, focusing on human studies that utilized ISAPP-recognized prebiotics as the sole intervention. Results: The analysis confirms that prebiotic supplementation consistently increased the abundance of beneficial bacteria (e.g., Bifidobacterium and Lactobacillus) and SCFA production. These changes are associated with significant clinical improvements, including enhanced stool frequency and consistency, strengthened intestinal barrier function, and modulated immune responses. Benefits have been documented in healthy individuals, children, the elderly, and those with conditions such as constipation, metabolic syndrome, and antibiotic-associated dysbiosis. However, significant inter-individual variability in response was evident, and the study designs showed notable heterogeneity in prebiotic type, dosage, and duration. Conclusions: Prebiotics are effective modulators of gut health, driving clinical benefits through selective microbial fermentation and SCFA production. The documented heterogeneity and variability highlight the need for future research to focus on personalized nutritional strategies. Key priorities include standardizing intervention protocols, elucidating dose–response relationships, integrating multi-omics data to link taxonomy to function, and exploring novel applications such as synbiotic formulations and gut–brain axis modulation. Full article

The global prevalence of obesity continues to rise and is a significant risk factor for the onset and progression of cardiovascular diseases. Despite the development of new pharmacological therapies, novel strategies are being explored to mitigate the impact of this disease. Intermittent fasting (IF) is a nutritional intervention that has gained popularity and shows potential as an innovative approach to weight management. This study aims to compile scientific evidence on various aspects of fasting, including its physiological effects, the molecular and thermogenic mechanisms involved, and recommendations regarding nutritional strategies during the refeeding period within the eating window. We conducted a narrative review, analyzing evidence available from PubMed/MEDLINE based on studies related to intermittent fasting, thermogenesis, and their associated outcomes. Our results demonstrate the existence of three commonly used IF protocols: alternate day fasting (ADF), periodic fasting (PF), and time-restricted eating (TRE). In addition to its effects on weight loss, IF has demonstrated notable benefits for cardiovascular health, oxidative stress, and metabolic function. Moreover, the interaction between the central nervous system and brown adipose tissue provides an alternative mechanism for the molecular regulation of thermogenesis. Nutritional patterns adopted during intermittent fasting play a crucial role in optimizing outcomes, with particular emphasis on the intake of proteins, fiber, bioactive compounds, and essential fatty acids during the feeding window. In summary, current evidence indicates that intermittent fasting provides a biologically robust framework for studying energy balance and holds promise for developing targeted nutritional interventions. Full article

To explore a safe and effective approach for producing strontium-enriched fish, in this study, we modified the feed for juvenile hybrid sturgeon (Acipenser baerii ♀ × Acipenser schrenckii ♂) and set three different levels of strontium chloride content in their diet (0 mg/kg (Sr0, control), 80 mg/kg (Sr80), and 160 mg/kg (Sr160)) for a period of 8 weeks, analyzing their growth performance, strontium enrichment, muscle nutrition, and hepatic physiological, biochemical, and transcriptomic characteristics. The results show that dietary strontium had no significant impact on sturgeon growth or survival rate (p > 0.05). The strontium content in tissues increased with dietary strontium levels, with the highest enrichment in bone plates (p < 0.05). However, muscle crude fat in the strontium-supplemented groups decreased significantly; the Sr160 group had higher glutamic acid, valine, docosahexaenoic acid methyl ester, lower myristic acid, palmitic acid, etc. (p < 0.05). In addition, strontium treatment alleviated hepatic lipid accumulation and mitochondrial swelling. Biochemical analyses revealed reduced plasma levels of Triglyceride (TG), Total Cholesterol (TC), Alanine Aminotransferase (ALT), and Aspartate Aminotransferase (AST), as well as decreased hepatic Malondialdehyde (MDA) content, while hepatic Glutathione (GSH) levels increased (p < 0.05). Transcriptomic data further showed that strontium downregulated the expression of fasn and tfrc and upregulated the expression of cpt1a, apoa1, cyp7a1, and slc3a2 (p < 0.05). In conclusion, dietary supplementation with 80–160 mg/kg strontium enables safe strontium enrichment in hybrid sturgeon, improves muscle nutritional quality, and protects liver function by regulating the genes related to lipid metabolism and antioxidant defense, providing a scientific basis for the development of strontium-enriched fish products. Full article

Background/Objectives: Vitamin D is a nutrient involved not only in bone metabolism but also in metabolic functions, and deficiency is common during adolescence. This study aimed to describe the distribution of serum 25-hydroxyvitamin D levels among Korean adolescents and to examine their associations with metabolic syndrome and its individual components. Methods: We analyzed data from the 2022–2023 Korea National Health and Nutrition Examination Survey. Adolescents aged 10–18 years with serum 25-hydroxyvitamin D measurements were included (unweighted N = 880). Weighted analyses were performed by categorizing serum 25-hydroxyvitamin D levels into quartiles. Associations between vitamin D quartiles and anthropometric and metabolic parameters were examined using complex-sample general linear models, and odds ratios for metabolic syndrome and its individual components according to vitamin D deficiency were estimated using complex-sample logistic regression models. Results: Weighted prevalence of vitamin D deficiency (<20 ng/mL) was 62.4%, higher in females than males. Higher 25(OH)D quartiles were inversely associated with obesity-related indices, including BMI, waist circumference, and waist-to-height ratio, after full adjustment (p for trend < 0.05). No significant associations were observed for blood pressure, fasting glucose, or lipid parameters. In dichotomous analyses (<20 vs. ≥20 ng/mL), vitamin D deficiency was associated with higher odds of waist circumference ≥ 90th percentile (OR 2.59), waist-to-height ratio > 0.5 (OR 2.63), and BMI ≥ 95th percentile (OR 1.89), while metabolic syndrome was not significant. Conclusions: Vitamin D appears to play an important role in metabolic health in adolescents and was particularly associated with general and central obesity. Full article