Search Results (823)

Background: Chronic obstructive pulmonary disease (COPD) is associated with systemic alterations in body composition, including muscle mass loss and fat redistribution, which may influence patient-reported outcomes. However, the independent contribution of bioimpedance-derived parameters, particularly phase angle, to quality of life (QoL) remains unclear. Methods: This exploratory pilot study included 75 clinically stable patients with moderate-to-severe COPD (GOLD stages II–III). Body composition was assessed using segmental multi-frequency bioelectrical impedance analysis with the InBody 770 system. Evaluated parameters included fat-free mass (FFM), skeletal muscle mass (SMM), percent body fat (PBF), visceral fat area (VFA), extracellular water-to-total body water ratio (ECW/TBW), bone mineral content (BMC), and phase angle (PhA). Quality of life was assessed using the WHOQOL-BREF questionnaire. Associations between body composition parameters and QoL domains were analyzed using Spearman correlation analysis and multivariable linear regression models. Results: Despite a median body mass index (BMI) within the normal range (23.4 kg/m²), body fat mass exceeded reference values in both men and women. Fat-free mass and skeletal muscle mass were located near the lower range of expected values. Correlation analysis demonstrated predominantly weak associations between body composition parameters and QoL domains. Significant positive correlations were identified between the psychological QoL domain and fat-free mass (ρ = 0.238, p = 0.041), skeletal muscle mass (ρ = 0.240, p = 0.040), basal metabolic rate (ρ = 0.236, p = 0.043), and bone mineral content (ρ = 0.249, p = 0.033). In multivariable regression models, fat-free mass and skeletal muscle mass demonstrated consistent positive associations with both physical and psychological QoL domains. Whole-body and segmental phase angle parameters did not demonstrate significant associations with QoL outcomes. Conclusions: In patients with COPD, BMI alone may inadequately reflect underlying alterations in body composition. Muscle-related parameters, particularly fat-free mass and skeletal muscle mass, demonstrated more consistent associations with physical and psychological aspects of quality of life than obesity-related indicators. These findings suggest that bioelectrical impedance analysis may provide additional clinically relevant information beyond BMI when assessing body composition and quality of life in patients with COPD. Full article

Background: Numerous gene variants are linked to an individual’s propensity to become overweight or obese. A commonly studied gene variant is the FTO single-nucleotide polymorphism (SNP) rs9939609. The FTO risk (A/-) allele associated with this SNP is linked with increased body fat percentage, body mass, BMI, and other lifestyle factors that may perpetuate an individual’s risk for obesity. This study investigated dietary behaviors in individuals engaged in varying levels of physical activity with and without the FTO risk allele. Methods: Using a cross-sectional design, adults completed the Three-Factor Eating Questionnaire (TFEQ-R18) and Food Craving Inventory (FCI) to assess dietary behaviors. Body composition was assessed using bioelectrical impedance analysis (in-body analyses). Results: Findings indicated that individuals with the FTO risk allele exhibited higher levels of cognitive restraint. No other significant differences were reported in all outcomes between groups. Regression analyses found that physical activity was significantly associated with multiple dietary behaviors (emotional eating, cravings for sweets, the behavioral aspect of fried and sweet cravings), while the FTO risk allele was related to higher cognitive restraint and lower behavioral fried food cravings. Conclusions: Combined, these findings indicate that anthropometric measures and most dietary behaviors did not differ across FTO risk variants in physically active individuals, although individuals with higher-risk genotypes exhibited greater cognitive restraint. Full article

Background: Muscle function determines overall health and is often impaired in metabolic syndrome and cancer, largely due to oxidative stress and inflammation. Olive mill wastewater (OMWW) is rich in bioactive polyphenols (e.g., hydroxytyrosol and verbascoside) that may hinder these potential pro-sarcopenic mechanisms, representing a potential nutraceutical to limit muscle health decline. Objective: To evaluate the effects of short-term supplementation with an OMWW-derived polyphenol extract (Oliphenolia^®, OMWW-OL) on muscle-related parameters and antioxidant biomarkers in adults at metabolic risk while maintaining dietary habits. Methods: This exploratory, hypothesis-driven secondary analysis was based on a single-arm longitudinal pilot study assessing patients at baseline (T0), after 30 days of supplementation (T1), and 30 days post-discontinuation (T2). Anthropometry, bioelectrical impedance, and biochemical assessments were performed. Results: Supplementation was associated with modest increases in skeletal muscle mass, muscle mass percentage, and wrist, arm, and calf circumferences. Fat mass decreased progressively, while total body water percentage and hydration status improved. Ferritin levels rose at T2, alongside increases in protein thiols (PSH) and Trolox equivalent antioxidant capacity (TEAC), suggesting improved iron status and reduced oxidative stress. Body weight and BMI decreased, as expected in a dietary intervention for metabolic syndrome, while muscle health showed a tendency toward improvement. Conclusions: Although the findings require cautious interpretation, short-term OMWW-OL supplementation was associated with modest but consistent directional changes in muscle-related and metabolic indicators in adults at metabolic risk. The results support hypothesis generation and highlight the need for larger studies to further explore the potential role of OMWW-OL in the context of cancer-associated sarcopenia. Full article

Objectives: This study aims to investigate the associations between dietary branched-chain amino acids (BCAAs) intake and appendicular skeletal muscle mass (ASM) as well as handgrip strength in Chinese adults. Methods: A total of 36,086 observations (54.32 ± 14.63 y) were included from the China Health and Nutrition Survey (CHNS) across three waves (2015, 2018, and 2022–2024). ASM was measured by bioelectrical impedance analysis, and handgrip strength was measured using a digital dynamometer. Dietary BCAA intake was assessed using three consecutive 24 h dietary recalls and adjusted for energy intake. Multilinear mixed-effect models were employed to examine the longitudinal association between BCAA intake and ASM. Multivariable regression was used to assess the cross-sectional association between BCAA intake and handgrip strength. Results: Dietary BCAA intake was significantly associated with ASM (β = 0.074, p < 0.05) with adjustment for potential confounding factors. This estimated positive effect increased with age in both males and females, and was consistently stronger in males. Compared with the lowest quintile (Q1), Q4 of dietary BCAA intake had higher handgrip strength (β = 0.721, p < 0.001). Stratified analyses showed that this association was more pronounced in males (Q4 vs. Q1: β = 1.016, p = 0.005) and in participants aged ≥65 years (Q4 vs. Q1: β = 1.024, p = 0.008). Conclusions: Dietary BCAA intake is recommended to maintain muscle mass and strength in Chinese adults. Full article

Background/Objectives: Evidence-based nutritional recommendations for obesity management require understanding of sex-specific and age-specific body composition patterns and their associations with metabolic biomarkers, habitual dietary intake and chronic low-grade inflammation. This study aimed to characterize body composition phenotypes in a large clinical cohort of adults with obesity, to evaluate associated metabolic and inflammatory biomarker patterns, to contextualise these patterns against habitual nutrient intake assessed in a dietary subcohort, and to derive age- and sex-specific nutritional recommendations based on the identified patterns. Methods: We performed a cross-sectional analysis of 29,544 adults with obesity (BMI ≥ 30; 21,374 women, 8170 men; age 30–69) who underwent multi-frequency bioelectrical impedance analysis (BIA; InBody 770). Biochemical assessments (fasting glucose, lipid profile, uric acid, HbA1c, insulin) were available for 2019 hospitalized patients from the same population. Habitual dietary intake was quantitatively assessed in a dietary subcohort of 423 patients using the validated Russian software-based questionnaire “Scientific Nutrition Analysis Tool”. Inflammatory biomarkers (high-sensitivity CRP, IL-6) and adipokines (leptin, adiponectin) together with serum 25(OH)D were measured in an inflammation/adipokine subcohort of 116 patients. A body composition phenotype with low relative muscle mass and high visceral fat (VFA ≥ 100 cm²) was defined using FNIH criteria (ALM/BMI < 0.789 men, <0.512 women). Benjamini–Hochberg FDR correction (q < 0.05) was applied for multiple comparisons. Results: The body composition phenotype prevalence increased progressively with age: men 24.6% (30–39) to 42.0% (60–69); women 10.3% (30–39) to 31.8% (60–69). Skeletal muscle mass (SMM) was positively associated with uric acid (r = +0.347, p < 0.001, FDR q < 0.05) and inversely associated with HDL-cholesterol (r = −0.321, p < 0.001, FDR q < 0.05)—both associations with direct nutritional implications. BMI was associated with fasting insulin (r = +0.233, p < 0.001, FDR q < 0.05). Women showed significant age-related metabolic differences between the 30–39 and 60–69 age groups: fasting glucose +12.9%, triglycerides +34.8%, uric acid +15.0% (all p < 0.001); in men, significant differences were observed for fasting glucose (+7.0%) and HbA1c (+5.2%) (both p < 0.001), while lipid parameters did not reach significance. In the dietary subcohort, habitual saturated-fat intake exceeded recommended values in 70–72% of patients of both sexes, dietary fibre intake was below recommended levels in 73–85%, and habitual calcium intake decreased significantly with age in women (1022 → 746 mg/day, p = 0.028). Serum CRP was elevated (median 5.59 mg/L, n = 59). In a separate extended laboratory subcohort, serum oestradiol declined markedly with age in women (55.0 → 16.8 pmol/L between 30–39 and 50–59 years, p < 0.001), consistent with the menopausal transition; serum testosterone in men remained stable across age groups; and 25(OH)D insufficiency (<30 ng/mL) was prevalent in 49.7–55.8% of patients. Conclusions: The identified sex-specific and age-specific body composition patterns provide a rationale, supported by observed dietary and inflammatory patterns, for targeted nutritional intervention: increased dietary protein, omega-3 fatty acids supplementation, low-glycemic-index dietary patterns, and purine restriction with hyperuricemia. Routine BIA-based nutritional screening combined with quantitative dietary assessment should begin at age 30, with preventive monitoring at age 40 and intensification of control at age 50, to guide personalized dietary planning in obesity. Full article

Sarcopenia in inflammatory bowel disease can significantly influence disease course. Since current assessment focuses mainly on muscle quantity, we aimed to evaluate muscle function in Crohn’s disease (CD) patients and identify those at increased risk of muscle function impairment. This cross-sectional study included 84 patients with CD (76.2% male, mean age 35 ± 11 years) receiving infliximab. Body composition was assessed by bioelectrical impedance analysis, muscle strength by handgrip strength (HGS), and physical performance by gait speed. Half of the cohort demonstrated reduced muscle strength relative to age- and sex-adjusted norms, while none met criteria for confirmed sarcopenia. One third of the patients had low physical performance and only one patient screened positive for sarcopenia. In multivariable linear regression, sex was the strongest independent predictor of HGS (p < 0.001), followed by ileocolonic disease localization, which was independently associated with lower HGS compared to ileal (p = 0.045) and colonic (p = 0.046). Hemoglobin remained an independent predictor of HGS after multivariable adjustment (p = 0.021). Low muscle strength is common in patients with CD treated with infliximab, even in the absence of low muscle mass. Ileocolonic disease localization and lower hemoglobin levels are predictors of low muscle strength, highlighting the importance of early and comprehensive muscle function assessment in this population. Full article

Background/Objectives: University students frequently exhibit suboptimal dietary habits, and even those enrolled in nutrition-related programmes may fail to meet recommended intakes of several key nutrients. This study aimed to assess changes in dietary intake and body composition over a single academic semester among university nutrition students. Methods: A prospective pre–post study was conducted with 102 students at the Czech University of Life Sciences Prague. Dietary intake was assessed using a 3-day food record and evaluated for energy, macronutrients, and specific micronutrients. Body composition was measured by a multi-frequency bioelectrical impedance analysis. Changes between baseline and follow-up were analysed using paired statistical tests with the false discovery rate correction. Predictors of follow-up body fat percentage were examined using an analysis of covariance. Results: At baseline, mean daily energy intake was 2114 ± 632 kcal. A particularly low intake was observed for dietary fibre (15.45 ± 8.46 g/day), potassium (2013 ± 954 mg/day), iodine (63.5 ± 69.8 µg/day), and vitamin D (2.31 ± 3.01 µg/day), whereas protein intake was relatively high. During follow-up, significant increases were observed in the intake of carbohydrates (+54.2 g/day), dietary fibre (+9.3 g/day), potassium (+766 mg/day), vitamin C (+69.2 mg/day), and magnesium (+86.2 mg/day), together with lower sodium and saturated fat intake (all adjusted p < 0.001). No significant short-term changes were found in body weight, body fat percentage, or skeletal muscle mass. Follow-up body fat percentage was primarily associated with baseline adiposity. Conclusions: One semester of nutrition-related education was associated with improved dietary intake, particularly for fibre and selected micronutrients, but not with measurable short-term changes in body composition. These findings suggest that nutrition education may support healthier dietary behaviour and may contribute to preventive healthcare strategies in young adults. Full article

Objectives: This study investigated the associations of biochemical and body water distribution parameters with dengue status, as well as their discriminatory ability, among hospitalized adults with febrile illnesses and evaluated whether dynamic changes in body water volumes were associated with length of hospital stay (LOS) in dengue patients. Methods: A prospective observational cohort study was conducted at a tertiary care hospital involving 186 hospitalized adults (age ≥ 18 years) with fever onset ≤ 5 days and suspected dengue. Body water parameters were assessed by bioelectrical impedance analysis (BIA) using the InBody S10 body composition analyzer at admission (T1), defervescence (T2), and discharge (T3) in dengue patients and at admission only in other febrile illness (OFI) cases. Laboratory data and LOS were retrieved from the hospital information system. Linear and logistic regression models were used to examine the associations and interactions. Discriminative performance was assessed using a receiver operating characteristic (ROC) curve analysis. Results: The proportion of dengue cases was 55.9% (n = 104). Higher levels of lymphocytes, hematocrit, hemoglobin, AST, and ALT were associated with an increased likelihood of dengue, whereas elevated WBC counts, neutrophils, platelets, CRP, sodium, chloride, and the extracellular water-to-total body water ratio (ECW/TBW) were associated with a reduced likelihood of dengue. ROC analysis indicated that WBC showed the best diagnostic performance. In dengue patients, a greater increase in ECW volume from admission to defervescence was associated with a longer LOS in males, and ratio-based body water parameters showed longitudinal variation across dengue phases. Conclusions: Several hematologic, biochemical, and BIA-derived body water parameters were associated with dengue status. Among dengue patients, dynamic ECW changes were associated with longer LOS in males, and ratio-based fluid indices were more sensitive than absolute water volumes in reflecting fluid redistribution throughout the dengue course. Full article

Background and Objective: Body mass index (BMI) is a worldwide screening standard but fails to distinguish between fat mass and fat-free mass. This study examines the prevalence and metabolic profile of the normal weight obesity (NWO) phenotype in a large cohort of young adults. Methods: A cross-sectional study of 4793 young adults (18–35 years) was conducted using bioelectrical impedance analysis (BIA). Participants were stratified into four phenotypes: underweight, healthy weight (HW), NWO, and obesity. Anthropometric indices, visceral fat area (VFA), and phase angle (PhA) were analyzed. Results: Within the normal BMI range (n = 2491), 40.6% (n = 1012) of patients were classified as NWO (percentage of body fat (PBF) >30% for women, >20% for men). NWO subjects showed a significantly higher VFA compared to the HW (+33.0 cm² in men and +24.3 cm² in women; p < 0.001) with a very large effect size (Cohen’s d > 2.0). Furthermore, a state of relative sarcopenia was identified, characterized by significantly lower skeletal muscle mass percentage (SMM%) and PhA (p < 0.001; d = −0.82), indicating compromised cellular integrity despite a normal BMI. Conclusions: BMI misclassifies 4 out of 10 young adults with excess adiposity. NWO is a high-risk phenotype linked to visceral adiposity and early cellular frailty. Incorporating BIA in routine screenings is essential to identify this invisible risk group. Full article

As life expectancy for people living with human immunodeficiency virus (HIV) (PLWH) increases, long-term comorbidities, such as bone mineral density (BMD) loss, have emerged as significant clinical challenges. This study evaluated the prevalence and determinants of skeletal demineralization in a contemporary Romanian HIV cohort. A cross-sectional study was conducted among 180 PLWH (mean age 41.86 ± 12.69 years) undergoing stable antiretroviral therapy. Bone health was assessed via dual-energy X-ray absorptiometry (DXA), while body composition and metabolic status were evaluated using bioelectrical impedance analysis (BIA) and serum lipid profiling. A high prevalence of reduced skeletal mass (58.3%) was observed, with 10% of the cohort diagnosed with osteoporosis at a mean age of only 45.7 years. Significant correlations were identified between osteoporosis and a history of AIDS, active smoking, and hypertriglyceridemia. Notably, women with osteoporosis exhibited significantly lower current CD4+ T-cell counts (268.4 ± 180.5 cells/μL) compared to those with normal BMD. While the body mass index was an inconsistent predictor of bone health, BIA-derived bone mass effectively identified subclinical depletion. Our findings underscore a phenotype of premature skeletal aging in PLWH, driven by an interplay of immunological history, metabolic disturbances, and lifestyle factors. Early screening via DXA and BIA, alongside aggressive management of modifiable risks, is essential for mitigating fragility fractures in this aging population. Full article

Limited data are available regarding the physiological profile of youth triathletes. The aim of this study was to characterize the physiological and body composition profile of Hungarian youth triathletes and to examine the relationships between anthropometric characteristics and aerobic performance indicators. Forty-one youth triathletes (20 females and 21 males; age: 15.8 ± 1.7 years), members of the Hungarian national development squad, participated in the study. Anthropometric and body composition parameters were assessed using standardized procedures and multi-frequency bioelectrical impedance analysis. Aerobic performance was evaluated using a graded cardiopulmonary exercise test on a treadmill with breath-by-breath gas analysis. Male athletes demonstrated higher body height, body mass, fat-free mass, and skeletal muscle mass compared with females (p < 0.05). Cardiopulmonary exercise testing revealed high aerobic capacity, with mean VO₂max values of 73.2 ± 5.4 mL·kg⁻¹·min⁻¹ in males and 63.1 ± 5.0 mL·kg⁻¹·min⁻¹ in females. The second ventilatory threshold occurred at approximately 82–86% of VO₂max. Strong positive correlations were observed between anthropometric parameters and absolute oxygen uptake (mL·min⁻¹), particularly for fat-free mass, skeletal muscle mass, and body surface area (r = 0.83–0.95). However, these relationships are influenced by body size and were weaker or inverse when relative oxygen uptake (mL·kg⁻¹·min⁻¹) was considered. Regression analyses further indicated that body composition variables, especially fat-free mass and skeletal muscle mass, were positively associated with aerobic performance, while body fat percentage was not a significant predictor when body size and sex were controlled. These findings are based on cross-sectional associations and should be interpreted as descriptive reference data for this population rather than predictive criteria. The results contribute to the characterization of physiological and anthropometric profiles in youth triathletes and may support future research and athlete monitoring. Full article

Systemic inflammation is influenced by regular physical activity and diet. While moderate exercise can transiently alter inflammatory markers, high-intensity activity may increase muscle turnover without substantially elevating systemic inflammation. The combined effects of physical activity and dietary inflammatory potential in healthy young men remain poorly defined. In this cross-sectional observational study, 233 healthy men aged 18–30 years were categorized according to physical activity level: low (NA, n = 52), moderate (A, n = 93), and high (S, n = 88). Anthropometry and body composition were assessed using bioelectrical impedance. Dietary intake was recorded over 4 days and used to calculate the Dietary Inflammatory Index (DII). Blood samples were collected and analyzed for complete blood counts, high-sensitivity C-reactive protein (hs-CRP), serum amyloid A (SAA), and creatine kinase (CK). Differences between groups were evaluated using the Kruskal–Wallis test with Dunn’s post hoc correction, and principal component analysis (PCA) was performed to explore multivariate inflammatory patterns. The highest BMI, fat percentage, and DII were observed in low-activity men, whereas fat-free mass and CK activity were greatest in highly active men. Slightly higher systemic inflammatory markers (hs-CRP and SAA) were observed in moderately active men compared to other groups. PCA revealed two principal axes: PC1 representing systemic inflammation and PC2 representing leukocyte distribution. Weak associations were found between DII and these components, indicating a limited link between dietary inflammatory potential and circulating inflammatory biomarkers. Body composition is strongly influenced by physical activity, with high activity promoting lean mass and moderate activity associated with modest elevations in inflammatory markers. Dietary inflammatory potential was only weakly associated with systemic inflammation, suggesting that exercise-induced physiological stress may play a more prominent role in shaping inflammatory profiles in healthy young men. Full article

Background: Body mass index (BMI) is widely used as a proxy of nutritional status and related lifestyle risk patterns in public health, yet it does not capture body composition–related heterogeneity in cardiometabolic risk. Evidence on whether a more detailed body composition assessment improves population-level screening efficiency remains inconsistent, particularly in Central European populations. Methods: We conducted a cross-sectional analysis of 868 Hungarian adults participating in a nationwide mobile screening program. Locally weighted regression identified sex-specific BMI inflection points for cardiometabolic risk. Stratified receiver operating characteristic (ROC) analyses compared BMI with bioelectrical impedance-derived parameters across five outcomes. Cost- and time-effectiveness of scalable screening strategies were modeled at the population level. Results: Cardiometabolic risk increased at BMI levels below current WHO thresholds (females: 21.8–22.3 kg/m²; males: 23.8–24.3 kg/m²). Overall, body composition parameters did not outperform BMI in the full population. Subgroup-specific differences were observed, particularly among men with BMI 24–36 kg/m² for atherosclerosis risk, suggesting limited and outcome-specific added value rather than broad superiority over BMI. Together, non-linear risk patterns, stratified performance, and population-level modeling converged on mid-range BMI intervals (females: 22–30 kg/m²; males: 24–30 kg/m²) as likely screening windows of phenotypic heterogeneity. Within these ranges, targeted InBody assessment may help refine risk assessment for selected individuals. A mixed screening strategy covering 52% of the population would cost 178.4% of BMI-only screening, while reducing throughput by 24.3%. Conclusions: Population-specific BMI thresholds may more accurately reflect early deviations in nutritional and cardiometabolic risk than current universal cutoffs. BMI remains a useful first-line marker, and body composition assessment may add complementary information in selected BMI ranges. Overall, these findings support a potentially useful, subgroup-specific screening approach, but the modeled cost and time trade-offs should be considered hypothesis-generating and require further validation. Full article

Background/Objectives: Malnutrition in cancer adversely affects treatment outcomes and survival. Early intervention through oral nutritional supplements (ONSs) and dietary counseling can improve outcomes. This study evaluated the evolution of nutritional and morphofunctional parameters over three months in malnourished patients with cancer undergoing a comprehensive nutritional support program comprising dietary counseling, physical activity, and a novel concentrated high-protein, high-calorie ONS (cHPHC-ONS) with a high intrinsic leucine content. Methods: A prospective, observational, multicenter cohort study was conducted across 18 public hospitals in Spain. Two hundred thirty malnourished patients with cancer were enrolled: 147 naïve (no ONS treatment in the last three months) and 83 non-naïve (who transitioned to cHPHC-ONS after inadequate response to initial ONSs). Nutritional status was assessed using Global Leadership Initiative on Malnutrition (GLIM) criteria and morphofunctional parameters via bioelectrical impedance analysis, nutritional ultrasound, handgrip strength, the Timed Up and Go (TUG) test, and analysis of biochemical parameters. Results: After three months, 23.8% achieved normal GLIM nutritional status (p < 0.0001), with a greater improvement seen in non-naïve patients (28.4%, p < 0.0001). Weight loss ceased in 42.6% (p < 0.0001). and inflammation resolved for 10.3% (p = 0.0015). Non-naïve patients experienced a significant increase in fat-free mass index (p = 0.0159), appendicular skeletal muscle index (p = 0.0248), and rectus femoris cross-sectional area (p = 0.0016). Muscle strength increased significantly by +1.7 kg (p = 0.0025), and TUG test time decreased by 1.13 s (p = 0.0003) overall. Conclusions: The comprehensive nutritional support program—including a novel cHPHC-ONS, along with dietary and physical activity guidance—significantly improved the nutritional and morphofunctional status of malnourished patients with cancer, with benefits particularly evident in non-naïve individuals. Limitations: Observational design, no control group, short follow-up, and unadjusted non-multivariable comparisons, limiting causal inference. Full article

Background: Critical illness is characterized by profound and rapidly evolving metabolic derangements driven by systemic inflammation, hypercatabolism, fluid shifts, and endocrine dysregulation. These dynamic changes markedly limit the accuracy of predictive equations, increasing the risk of both underfeeding and overfeeding. Indirect Calorimetry Energy represents the gold standard for measuring energy expenditure, while bioelectrical impedance vector analysis (BIVA) provides complementary insights into hydration status, cellular integrity, and body cell mass. In palliative care, AI-supported integration of indirect calorimetry and BIVA enables goal-concordant artificial nutrition by aligning energy delivery with real-time metabolic status while minimizing symptom burden. Artificial intelligence (AI) has emerged as a promising tool to integrate these heterogeneous data streams and support adaptive nutritional strategies. Methods: We conducted a structured narrative review of the literature published between 2000 and 2025 using PubMed, Scopus, Embase, and Web of Science. Artificial intelligence was not used to perform the literature search or study selection. Instead, AI was analyzed as a clinical and technological component within the included studies and explored as a future enabling strategy. Eligible publications involved adult critically ill patients and addressed indirect calorimetry, BIVA-derived parameters, or AI-based metabolic modeling applied to nutritional support. Given the heterogeneity of study designs and outcomes, findings were synthesized qualitatively. Results: Predictive equations showed substantial inaccuracy in unstable metabolic states, with errors frequently exceeding ±20–40%. Indirect calorimetry enabled individualized assessment of energy expenditure but remained limited by intermittent availability. Serial BIVA assessments consistently identified clinically relevant alterations in hydration status, body cell mass, and phase angle, the latter being strongly associated with adverse outcomes. Studies incorporating AI demonstrated improved integration of calorimetry, BIVA, and clinical variables, allowing identification of metabolic phenotypes, anticipation of metabolic shifts, and generation of adaptive nutritional recommendations. Conclusions: This narrative review highlights the complementary roles of Indirect Calorimetry and BIVA in characterizing metabolic needs in critical illness. Artificial intelligence does not replace these tools but enhances their clinical utility by integrating multidimensional data into dynamic, patient-specific nutritional strategies. The combined AI–IC–BIVA approach represents a promising framework for metabolic precision nutrition in the ICU, warranting prospective validation. Full article