HMB Supplementation Research Articles

Nutritional management for institutionalized elderly people with sarcopenia: Integrative review

Objective: To identify the scientific evidence available on nutritional conducts to prevent the aggravation and treat institutionalized elderly people with sarcopenia. Methods: Integrative review conducted in the databases: LILACS, PUBMED, EBSCO and SciELO, from the descriptors: Diet Therapy; Elderly; Long-Stay Institution for the Elderly; Sarcopenia. The PICO strategy was used to develop the guiding question. Articles that answered the guiding question "what is the available evidence on nutritional management for institutionalized elderly people with sarcopenia to prevent the worsening and treatment of the disease" were included. Literature review: Six articles that responded to the theme were included in the integrative review. It was found that oral supplements plus high quality protein, vitamin D, Medium Chain Triglycerides (MCTs), beta-hydroxy-beta-methylbutyric acid (HMB) and leucine were nutritional interventions used to prevent the aggravation and treat sarcopenia in institutionalized elderly people. The practice of physical exercises was considered as an alternative intervention combined with nutritional conducts in order to improve results. Conclusion: Nutritional interventions of oral supplementation of high quality protein, vitamin D, TCMs, HMB and leucine may be beneficial to prevent the onset of sarcopenia and to treat institutionalized elderly people with sarcopenia.

Resveratrol and β-hydroxy-β-methylbutyric acid supplementation promotes ileal development and digestive function by altering microbial community abundance and metabolites in Tibetan sheep.

The effects of resveratrol (RES) and β-hydroxy-β-methylbutyric acid (HMB) on phenotype, immunity, digestive enzyme activity and short-chain fatty acids (SCFAs) contents in ileum of Tibetan sheep were investigated. A total of 120 two-month-old Tibetan sheep (15.5 ± 0.14 kg) were randomly allocated to 4 treatments: control group (basal diet), RES group (basal diet +1.5 g RES/d), HMB group (basal diet +1.25 g HMB/d), RES-HMB group (basal diet +1.5 g RES/d + 1.25 g HMB/d). Results indicated that dietary RES and (or) HMB supplementation significantly improved the phenotype (mucosal thickness and villus width), SCFAs concentrations, and digestive enzymes (lipase, cellulase, and α-amylase) (p < 0.05). The relative abundance of Brevibacillus, Clostridium sensu stricto 3, and Eubacterium hallii group were increased, while the abundance of Ruminococcus and Mogibacterium were decreased (p < 0.05) in the RES-HMB group. The metabolic profiling indicated an increase in the differential metabolites (DMs) including L-arginine, butanoic acid, D-mannose, and retinol were increased in the RES-HMB group (p < 0.05). In summary, our results suggested that RES and (or) HMB supplementation improved SCFAs concentration by up-regulating the microbial community abundance (Brevibacillus, Clostridium sensu stricto 3, and Eubacterium hallii group) and metabolism (L-arginine, butanoic acid, D-mannose, and retinol), thus contributing to ileal morphology and digestive enzyme activity. These findings may provides a novel reference for the nutritional regulation to improve the production of Tibetan sheep.

Correlating changes in intramuscular adipose tissue in sarcopenic surgical patients undergoing prehabilitation with HMB supplementation – HEROS pilot study

Correlating changes in intramuscular adipose tissue in sarcopenic surgical patients undergoing prehabilitation with HMB supplementation – HEROS pilot study

Effects of β-hydroxy-β-methylbutyrate (HMB) supplementation on lipid profile in adults: a GRADE-assessed systematic review and meta-analysis of randomized controlled trials.

The regulation of lipid metabolism is crucial for preventing cardiovascular diseases, which are among the leading causes of mortality worldwide. β-hydroxy-β-methylbutyrate (HMB) has garnered attention for its potential role in modulating lipid profiles. However, the magnitude of these effects are unclear due to the heterogeneity of the studies. This study aimed to provide a comprehensive overview of the randomized controlled trials (RCTs) that have examined the effects of HMB on lipid profiles in adults. Databases including PubMed, Web of Science, and Scopus, were searched for relevant studies through January 2024. The study protocol was also registered at Prospero (no. CRD42024528549). Based on a random-effects model, we calculated WMDs and 95% confidence intervals (CIs). The outcomes assessed included total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). Sensitivity, subgroup and meta-regression analyses were also conducted. Our analysis included a total of 10 RCTs comprising 421 participants. The pooled data revealed no significant effect of HMB supplementation on TC (WMD: -2.26 mg/dL; 95%CI: -6.11 to 1.58; p = 0.25), TG (WMD: -2.83 mg/dL 95% CI: -12.93 to 7.27; p = 0.58), LDL-C (WMD: 0.13 mg/dL; 95%CI: -3.02 to 3.28; mg; p = 0.94), and HDL-C (WMD: -0.78 mg/dL; 95%CI: -2.04 to 0.48; p = 0.22). The quality of evidence was rated as moderate to low for all outcomes. The current evidence from RCTs suggests that HMB supplementation does not significantly alter lipid profiles, including TC, TG, LDL-C, and HDL-C. Further research is warranted to confirm these results and explore the potential mechanisms of action of HMB. https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=528549, CRD42024528549.

Effects of exercise with or without β-hydroxy-β-methylbutyrate supplementation on muscle mass, muscle strength, and physical performance in patients with sarcopenia: a systematic review and meta-analysis.

This systematic review and meta-analysis aimed to assess the effects of exercise with/without β-hydroxy-β-methylbutyrate (HMB) supplementation on muscle mass, muscle strength, physical performance, and body composition in patients with sarcopenia. A literature search for randomized controlled trials (RCTs) on the effects of exercise with or without HMB supplementation on muscle mass, muscle strength, physical performance, and body composition in patients with sarcopenia was conducted using PubMed, Web of Science, EBSCO, The Cochrane Library, EMBASE, Scopus, Science Direct, China Knowledge Resource Integrated Database (CNKI), and Wan Fang database. The search was limited to studies published up to April 2024 for each database. The outcome measures included muscle mass, muscle strength, physical performance, and body composition. The Cochrane Risk of Bias Assessment Tool was used to evaluate the quality of the included literature, and RevMan 5.4 software was employed to perform a meta-analysis of the outcome indicators. Five RCTs involving 257 elderly patients with sarcopenia were included in this study. Meta-analysis showed that in terms of physical performance, exercise with HMB supplementation significantly increased gait speed in sarcopenic patients compared to the exercise combined with the placebo group (SMD = 0.48, 95% CI: 0.15 to 0.82, p = 0.005), but exercise combined with HMB supplementation did not have significant effects on SMI (SMD = 0.06, 95% CI: -0.20 to 0.32, p = 0.66), grip strength (SMD = 0.23, 95% CI: -0.05 to 0.52, p = 0.11), five-time chair stand test (SMD = -0.83, 95% CI: -1.88 to 0.21, p = 0.12), fat-free mass (SMD = 0.04, 95% CI: -0.26 to 0.35, p = 0.78), BMI (SMD = -0.09, 95% CI: -0.43 to 0.25, p = 0.60), and fat mass (SMD = 0.01, 95% CI: -0.25 to 0.27, p = 0.94). The current evidence indicates that exercise with HMB supplementation may enhance physical performance in patients with sarcopenia compared to exercise with the placebo group. However, the effects on muscle mass, muscle strength, and body composition are likely minimal. The above findings are limited by the number of included studies and require further validation through high-quality studies. Prospero (CRD42024500135).

Inhibition of BCAT1-mediated cytosolic leucine metabolism regulates Th17 responses via the mTORC1-HIF1α pathway

Branched-chain amino acids (BCAAs), particularly leucine, are indispensable AAs for immune regulation through metabolic rewiring. However, the molecular mechanism underlying this phenomenon remains unclear. Our investigation revealed that T-cell receptor (TCR)-activated human CD4+ T cells increase the expression of BCAT1, a cytosolic enzyme responsible for BCAA catabolism, and SLC7A5, a major BCAA transporter. This upregulation facilitates increased leucine influx and catabolism, which are particularly crucial for Th17 responses. Activated CD4+ T cells induce an alternative pathway of cytosolic leucine catabolism, generating a pivotal metabolite, β-hydroxy β-methylbutyric acid (HMB), by acting on BCAT1 and 4-hydroxyphenylpyruvate dioxygenase (HPD)/HPD-like protein (HPDL). Inhibition of BCAT1-mediated cytosolic leucine metabolism, either with BCAT1 inhibitor 2 (Bi2) or through BCAT1, HPD, or HPDL silencing using shRNA, attenuates IL-17 production, whereas HMB supplementation abrogates this effect. Mechanistically, HMB contributes to the regulation of the mTORC1-HIF1α pathway, a major signaling pathway for IL-17 production, by increasing the mRNA expression of HIF1α. This finding was corroborated by the observation that treatment with L-β-homoleucine (LβhL), a leucine analog and competitive inhibitor of BCAT1, decreased IL-17 production by TCR-activated CD4+ T cells. In an in vivo experimental autoimmune encephalomyelitis (EAE) model, blockade of BCAT1-mediated leucine catabolism, either through a BCAT1 inhibitor or LβhL treatment, mitigated EAE severity by decreasing HIF1α expression and IL-17 production in spinal cord mononuclear cells. Our findings elucidate the role of BCAT1-mediated cytoplasmic leucine catabolism in modulating IL-17 production via HMB-mediated regulation of mTORC1-HIF1α, providing insights into its relevance to inflammatory conditions.

Multi-Omics Revealed Resveratrol and β-Hydroxy-β-methyl Butyric Acid Alone or in Combination Improved the Jejunal Function in Tibetan Sheep.

Previous research studies confirmed that both resveratrol (RES) and β-hydroxy-β-methyl butyric acid (HMB) improved growth performance by altering intestinal microbiota. However, the mechanism underlying of RES and HMB on intestinal function remains unclear in ruminant. In this study, supplements of RES and HMB alone or in combination were evaluated as promoters of antioxidant capacity, immune response and barrier function, and modulators of the microbiota and metabolite profiles in the jejunum of Tibetan sheep. A total of 120 two-month-old Tibetan rams were randomly divided into four treatments (n = 30 per treatment), which were supplemented with a basal diet with 1.5 g RES/d (RES group), 1.25 g HMB/d (HMB group), 1.5 g RES/d plus 1.25 g HMB/d (RES-HMB group), and without additions (Control group). The results showed that RES and HMB improved the antioxidant capacity (CAT, GSH-Px, SOD, and T-AOC), immunity (IgA, IgG, and IgM), and digestive enzyme activity (α-amylase, lipase, and chymotrypsin) of the experimental lambs (p < 0.05). Additionally, jejunal morphology including villus width, villus height, and muscle layer thickness exhibited a significant difference when rams were fed diets supplemented with RES and HMB (p < 0.05). Furthermore, the determination of fermentation parameters showed that the butyrate concentration in the RES-HMB group was greater than those in the C and RES groups (p < 0.05). When compared to the C group, barrier-related gene expression (MUC-2, ZO-1, and IL-10) was significantly increased in the RES-HMB group (p < 0.05). Dietary RES and (or) HMB supplementation significantly increased the abundance of Methanobrevibacter, Actinobacteriota and Bacillus (p < 0.05). The abundance of differential bacteria was positively associated with butyrate concentration (p < 0.05). Metabolome analysis revealed that alpha ketoglutarate, succinic semialdehyde, and diacetyl as well as butanoate metabolism pathways connected to the improvements in butyrate concentration by RES and (or) HMB supplementation. Collectively, our results suggested that RES and (or) HMB supplementation improved butyrate concentration via regulating the microbial community (Methanobrevibacter, Actinobacteriota and Bacillus) and metabolism (alpha ketoglutarate, succinic semialdehyde, and diacetyl), thus contributing to jejunal morphology, antioxidant capacity, immune response, digestive enzyme activity, and barrier function.

Effect of a 12-week nutritional intervention in the food intake of patients on the waiting list for liver transplantation: A secondary analysis of a randomized controlled trial

BackgroundInadequate food intake contributes to malnutrition in patients with cirrhosis on the waiting list for liver transplantation (LTx). ObjectiveTo evaluate food intake during 12 weeks of nutritional follow-up and assess factors independently associated with the difference between caloric and protein intake in LTx patients. MethodsA secondary analysis of data from a randomized controlled trial that evaluated the effects of HMB supplementation in patients on a liver transplant waiting list. Dietary guidelines for patients with cirrhosis were used to prescribe the nutritional plan (35kcal/kg; 1.5g/kg dry weight for protein) and to evaluate the nutritional goals (30kcal/kg; 1.2g/kg dry weight for protein). Food intake was assessed in six moments: Baseline, week 0(W0), week 2(W2), week 4(W4), week 8(W8), and week 12(W12). ResultsForty-seven patients (55.0±10.6y;72.3% male) were evaluated. Only 25.5% (n=12) of patients achieve nutritional goals at the end of the study. The mean energy intake in baseline was 1782±784kcal (27.6±13.2kcal/kg) without difference between times. The protein intake increased between week W0 [63.4±29.8g; 0.8(0.2-2.2g/kg)] and W8 [72.0±28.0g; 1.0(0.4–2.6g/kg); p=0.03; p=0.03, respectively]. The consumption of cholesterol, calcium, phosphorus, magnesium, iron, and niacin increased (p<0.05), as well as the consumption of the leguminous; roots and tubers; dairy; and meat, poultry, and fish groups through the time (p<0.05). The presence of ascites, patients nourished, frailty index classification, short physical performance battery score, systemic symptoms, and emotional function were independently associated with the caloric intake difference W12-Baseline (p<0.05). Diabetes mellitus, patients with moderately malnourishment, poor performance, fatigue, systemic symptoms, and emotional function were independently associated with the difference in protein intake between W12-Baseline (p<0.05). ConclusionPatients on the liver transplant waiting list showed slight food intake improvement during the follow-up, but few met nutritional guidelines. Various clinical and nutritional factors independently affected energy and protein intake from W12 to baseline.

The Effect of β-Hydroxy-β-Methylbutyrate on Muscle Strength and Functional Outcomes in Older Adults

Nutritional intervention is increasingly being recognized as playing an important role in functional status. The supplementation with β‑hydroxy-β-methylbutyrate (HMB), which is a metabolite of an essential amino acid, may be an effective nutritional intervention to improve muscle strength and functionality in older adults. The aim of this narrative review was to present an updated overview of the effects of HMB supplementation in older adults, specifically on muscle strength and functional outcomes. A PubMed database search was performed and only randomized controlled trial studies were included. More than half of the 14 analyzed studies reported that HMB supplementation improved muscle strength and other functional outcomes. HMB supplementation has demonstrated some promising effects on muscle strength and functional outcomes in older adults with different conditions of health and physical activity.

Effects of multicomponent training and HMB supplementation on disability, cognitive and physical function in institutionalized older adults aged over 70 years: a cluster-randomized controlled trial

ObjectivesTo investigate the synergist effects of exercise and β-hydroxy β-methylbutyrate (HMB) supplementation on disability, cognitive and physical function, and muscle power in institutionalized older people. DesignCluster-randomized controlled trial. ParticipantsSeventy-two institutionalized older adults (age = 83 ± 10 years old; 63% women) were randomized in four groups: exercise plus placebo (EX), HMB supplementation, EX plus HMB supplementation (EX + HMB), and control (CT). InterventionThe exercising participants completed a 12-week tailored multicomponent exercise intervention (Vivifrail; 5 days/week of an individualized resistance, cardiovascular, balance and flexibility program), whereas the HMB groups received a drink containing 3 g/day of HMB. MeasurementsParticipants were assessed Pre and Post intervention for disability and cognitive function (validated questionnaires), physical function (short physical performance battery, SPPB), handgrip strength and sit-to-stand relative muscle power. Linear mixed-effect models were used to compare changes among groups. ResultsCompared to baseline, both EX and EX + HMB improved cognitive function (+2.9 and +1.9 points; p < 0.001), SPPB score (+2.9 points and +2.4 points; p < 0.001) and relative muscle power (+0.64 and +0.48 W·kg−1; p < 0.001), while CT and HMB remained unchanged (p > 0.05). Significant between-group differences were noted between CT, EX and EX + HMB for cognitive function (p < 0.01), between CT and EX + HMB for physical function (p = 0.043), and between CT, EX and EX + HMB for relative muscle power (p < 0.001). ConclusionThe Vivifrail exercise program was effective in improving cognitive and physical function, and muscle power in nursing home residents, while HMB supplementation did not provide additional benefits when combined with exercise. These results emphasize the importance of physical exercise interventions in very old people as an essential basis for improving their overall health and quality of life.

ß-Hydroxy-ß-methylbutyrate: A feed supplement influencing performance, bone metabolism, intestinal morphology, and muscle quality of laying hens: a preliminary one-point study

Laying hens, selectively bred for high egg production, often suffer from bone fragility and fractures, impacting their welfare and causing economic losses. Additionally, gut health and muscle quality are crucial for overall health and productivity. This study aimed to evaluate the effects of ß-Hydroxy-ß-methylbutyrate (HMB) supplementation on performance, bone metabolism, intestinal morphology, and muscle quality in laying hens. Forty-eight Bovans Brown hens were divided into a control group and an HMB-supplemented group (0.02% HMB in diet). The study spanned from the 31st to the 60th wk of age. Assessments included bone mechanical testing, serum hormonal analysis, histological analysis of bone and intestine, and muscle quality analysis. The HMB supplementation led to decreased feed intake without affecting body weight or laying rate in laying hens. It caused an increase in both mean daily and total egg weight, indicating improved feed utilization, without influencing the feed intake to egg weight ratio. Enhanced bone formation markers and altered intestinal morphometric parameters were observed, along with improved trabecular bone structure. However, no changes in measured other bone quality indices, including geometric, densitometric, or mechanical properties were observed. Muscle analysis revealed no significant changes in overall meat quality, except for a decrease in cholesterol content and alterations in the fatty acid profile, notably a reduction in total n-3 polyunsaturated and total polyunsaturated fatty acids (PUFA). In conclusion, although not all effects of HMB supplementation were unequivocally beneficial, the positive changes in performance data and trabecular bone microarchitecture support further research into various doses and durations of supplementation. Such studies are necessary to fully understand and optimize the benefits of HMB for enhancing the health and productivity of laying hens.

Effects of HMB on Endurance Performance in a Healthy Population: A Systematic Review and Meta-Analysis.

Fernández-Landa, J, Todorovic, N, Santibañez-Gutierrez, A, Ostojic, SM, Calleja-González, J, Sekulic, D, and Mielgo-Ayuso, J. Effects of HMB on endurance performance in a healthy population: a systematic review and meta-analysis. J Strength Cond Res 38(4): e202-e210, 2024-β-hydroxy-β-methylbutyrate (HMB) has been used extensively as a dietary supplement for athletes and physically active people. However, the ergogenic effect of HMB supplementation on endurance performance is still unclear. Therefore, this systematic review and meta-analysis (SRMA) aimed to assess HMB supplementation on endurance performance and V̇O 2 max . This SRMA followed PRISMA guidelines. Three electronic databases were searched (PubMed/Medline, Web of Science [WOS], and Scopus) from inception until April 3, 2023. In this SRMA, human experimental trials, controlled with a placebo group, assessing the effect of HMB supplementation on endurance performance in a healthy population were included. The quality of the studies was assessed by the Physiotherapy Evidence Database (PEDro) scale. The study protocol was registered in the Prospective Register of Systematic Review (PROSPERO): CRD42022341790. Eleven studies involving 279 participants met the inclusion criteria. The results displayed a significant improvement on endurance performance (pooled standardized mean difference [SMD] = 0.58 [0.28-0.87]) and V̇O 2 max (pooled SMD = 0.58 [0.21-0.95]) after HMB ingestion. Moreover, after the exclusion of the studies not evenly distributed around the base of the funnel plot, the results continued to be significantly positive in endurance performance (pooled SMD = 0.38 [0.22-0.53]) and V̇O 2 max (pooled SMD = 0.25 [0.09-0.42]). In conclusion, HMB (3 g·d -1 ) ingestion during 2-12 weeks significantly improves endurance performance and V̇O 2 max .

Association between endogenous plasma beta-hydroxy-beta-methylbutyrate levels and frailty in community-dwelling older people.

Frailty is a key element in healthy ageing in which muscle performance plays a main role. Beta-hydroxy-beta-methylbutyrate (HMB) supplementation has shown favourable effects in modulating protein synthesis, improving muscle mass and function in interventional studies. Decreased age-related endogenous HMB levels have been shown in previous studies. The aim of the present study is to assess whether there is an association between endogenous plasma HMB levels and frailty. Data from 1290 subjects (56.98% women; mean±standard deviation age 74.6±5.95years) from the Toledo Study for Healthy Aging were obtained. Participants had their frailty status qualified according to Fried's Frailty Phenotype (FFP) score and the Frailty Trait Scale in its 12-domain version (FTS-12). Plasma HMB levels were analysed by an ultrahigh-performance liquid chromatography tandem mass spectrometry. Differences between groups (frail vs. non-frail) were tested using Mann-Whitney U test, Kruskal-Wallis test and chi-squared test. The association between HMB and frailty was assessed by multivariate linear and logistic regressions when frailty was analysed as continuous and binary, respectively. Models were adjusted by age, gender, comorbidity, body composition and protein intake. HMB levels were lower in those aged ≥75years than in those aged 65-74years, with an inverse linear relationship between age and HMB levels (β=-0.031; P=0.018), mainly accounted by males (β=-0.062; P=0.002). HMB levels were higher in men (0.238±0.065 vs. 0.193±0.051ng/mL; P≤0.001). HMB levels were significantly lower in frail than in non-frail individuals: 0.204±0.058 versus 0.217±0.063ng/dL (P=0.001) according to the FFP and 0.203±0.059 versus 0.219±0.063ng/mL (P<0.001) according to FTS-12. These differences showed a dose-dependent profile when we compared them by quintiles of HMB (P for trend: 0.022; 0.012 and 0.0004, respectively, for FFP, FTS-12 binary and FTS-12 continuous). Variables associated with low HMB levels were body mass index, strength, exhaustion and weight loss. Frailty was associated with HMB levels in all the adjusted models, including the fully adjusted ones, no matter the tool used (odds ratio: 0.45 [0.26, 0.77] for FFP and 0.36 [0.20, 0.63] for FTS-12 binary; β=-4.76 [-7.29, -2.23] for FTS-12 score). This association was also observed when the analyses were done by quintiles, showing such association since Q4 (FFP), Q2 (FTS-12 binary) and Q3 (FTS-12 score). The associations were observed in the whole sample and in each gender. There is an inverse association between HMB levels and frailty status. These findings support the design of targeted clinical trials to evaluate the effect of HMB supplementation in older frail people with low HMB levels.

Beta-hydroxy-beta-methylbutyrate supplementation preserves fat-free mass in collegiate boxers during acute body mass loss.

Acute body mass loss before competitions in combat sports usually leads to loss in fat-free mass. Beta-hydroxy-beta-methylbutyrate (HMB) has been shown to increase skeletal muscle mass and muscle strength in various muscle wasting conditions. This study investigated the effect of HMB supplementation on body composition and sport-specific performance in well-trained boxers consuming a hypocaloric diet. Twelve male college boxers were divided into the HMB and placebo (PLA) groups using a body weight-matched single-blind parallel design. The study comprised a 6-day weight loss period (days 1-6), followed by a 3-day competition period (days 7-9). The participants in both the groups consumed 16 kcal/kg/day, including 1.6-1.7 g/kg of carbohydrates, 1.2-1.3 g/kg of protein, and 0.45-0.5 g/kg of fat during the 9-day period. The HMB group consumed 3 g/day HMB. Body composition measurement, isometric mid-thigh pull (IMTP), and a simulated boxing match were performed at baseline and on days 7, 8, and 9. Fasting blood samples were collected on the day before day 1 and on days 7, 8, and 9. Body mass was significantly decreased after the 6-day weight loss period (HMB group: baseline: 69.4 ± 11.2 kg, day 7: 67.1 ± 11.2 kg; PLA group: baseline: 68.6 ± 12.1 kg, day 7: 65.7 ± 11.5 kg, P < 0.05) while it was unchanged on the 3-day competition period in both the groups. Fat-free mass in the HMB group was maintained throughout the 9-day period (baseline: 56.7 ± 9.3 kg, day 7: 56.3 ± 8.7 kg, day 9: 55.8 ± 9.5 kg) whereas it significantly decreased on days 7 and 9 compared to the baseline in the PLA group (baseline: 55.2 ± 6.4 kg, day 7: 54.1 ± 6.6 kg, day 9: 54.0 ± 6.6 kg, P < 0.05). In the PLA group, the average and maximal heart rates in round 1 and the average heart rate in round 2 on days 8 and 9 were significantly lower than those at baseline, while these parameters were unchanged in the HMB group. The maximal force and the rate of force development in the IMTP remained unchanged among the different timepoints in both the groups. The blood biochemical parameters were similar at any timepoint between the PLA and HMB groups. HMB supplementation during acute weight loss may preserve fat-free mass and maintain heart rate response in subsequent simulated matches in well-trained boxers. In addition, HMB supplementation had a nonsignificant effect on glucose, fat, and protein metabolism during energy restriction.

Beta-hydroxy-β-methyl butyrate-supplemented diet for broiler chickens is more conducive to dietary protein reduction than a leucine-supplemented diet until 21 days old.

Dietary l-leucine or its metabolite 𝛽-hydroxy-𝛽-methylbutyrate (HMB) has a crucial role in the muscle protein metabolism of broilers during the first few-week growing period. The present study aimed to evaluate the effects of l-leucine (LLPD) or HMB (HLPD) supplementation in a low-protein diet (20%, LPD) until 21 days old on performance, carcass weight, muscle yield and meat quality, as well as intestinal morphometry, in broiler chickens. From days 1-42, LPD decreased body weight gain and feed intake (FI) and increased feed conversion ratio compared to a standard protein diet (22%, SPD). The LLPD and HLPD did not affect FI, but the LLPD decreased the body weight gain and increased the feed conversion ratio compared to the SPD. The LPD group had lower body and muscle weights than other groups. Compared to LPD, HLPD increased dressing percentage. The LPD decreased the serum insulin-like growth factor-1 content compared to the SPD and LLPD. The duodenal villus height of the LPD and LLPD broilers was smaller than those of the SPD and HLPD birds. The HLPD broilers had lower duodenal villus width than the SPD birds. The duodenal crypt depth and ileal mucosal thickness were higher in the HLPD group than in other groups. The HLPD and LLPD enhanced the ileal villus height compared to the SPD. The LLPD and HLPD treatments did not affect meat quality traits compared to the SPD treatment. Dietary HMB could be a conducive approach to reducing dietary protein for broilers until 21 days old. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Evaluation of Feeding Beta-Hydroxy-Beta-Methylbutyrate (HMB) to Mouse Dams during Gestation on Birth Weight and Growth Variation of Offspring.

This study was designed to determine if feeding β-hydroxy-β-methylbutyrate (HMB) to pregnant mice would improve birth weight uniformity and growth performance of offspring. Dams (Agouti Avy) were assigned to one of four treatments: control (CON; n = 13), low-level HMB (LL; 3.5 mg/g; n = 14), high-level HMB (HL; 35 mg/g; n = 15), and low-level pulse dose fed from gestational days 6 to 10 (PUL; 3.5 mg/g; n = 14). Randomly selected dams (n = 27) were euthanized on gestational day 18 to collect placentae and pup weights. The remaining dams gave birth and lactated for 28 days. Dams only received HMB during gestation. Dietary HMB did not influence the performance of dams. Dietary treatment during gestation did not affect litter size or birth weight of pups. Variation was not different among treatments in terms of birth weight of offspring. Placental weights were not affected by treatments. Overall, growth performance of offspring after weaning was similar among all treatments. Body composition of offspring at 5 and 8 weeks of age was similar regardless of HMB treatment during gestation. In conclusion, dietary HMB supplementation in pregnant mice did not affect birth weight, variations in birth weight, or growth performance of offspring.

Yolk Fatty Acid Profile and Amino Acid Composition in Eggs from Hens Supplemented with ß-Hydroxy-ß-Methylbutyrate.

In recent years, a supplementation of livestock animals, including poultry, with β-Hydroxy-β-methylbutyrate (HMB) has gained attention for its effects on protein and fat metabolism. This study investigates the effects of HMB in the laying hen diet on egg quality, focusing on amino acid and fatty acid composition. Laying hens were supplemented with 0.02% HMB, with performance parameters and egg components analyzed. HMB supplementation led to increased albumen weight, influencing egg weight while also reducing feed intake per egg without affecting laying rate, yolk indices, fat, or cholesterol content. Notably, the study revealed significant changes in egg amino acid and fatty acid profiles due to HMB supplementation. Various amino acids, including glycine, serine, and isoleucine, were altered in the yolk, impacting nutritional value and potential health benefits. Regarding fatty acids, the study observed changes in both saturated as well as n-6 and n-3 fatty acids, affecting the overall lipid profile of egg yolks. However, the shifts in fatty acid composition could have implications for cardiovascular health due to altered ratios of n-6/n-3 fatty acids. Further research is required to comprehensively understand the implications of these findings for consumer-oriented egg quality and health benefits.

Different effects of dietary β-hydroxy-β-methylbutyrate on composition of fatty acid and free amino acid, and fatty metabolism in the different muscles of broilers

In the study, 336 broiler chickens were selected to explore dietary effects of different β-hydroxy-β-methylbutyrate (HMB) levels (0 (control), 0.05, 0.10, and 0.15%) on the compositions of fatty acids and free amino acids, and lipid metabolism in the different muscles of broilers. In the breast muscle, dietary HMB supplementation hardly affected the free amino acid composition (P > 0.05). Compared to the control group, dietary 0.10 and 0.15% HMB supplementation decreased the content of C18:1n9c and thus the monounsaturated fatty acid (MUFA), and dietary 0.15% HMB supplementation increased the sum of saturated fatty acids (SFA) (P < 0.05). Moreover, compared to the control group, dietary 0.05 and 0.10% HMB increased the mRNA expression of proliferator activated receptor-γ and the activity of fatty acid synthase (FAS), and dietary 0.10% HMB increased the acetyl-CoA carboxylase activity (P < 0.05). In the leg muscle, dietary 0.10 and 0.15% HMB increased the MUFA content and decreased the polyunsaturated fatty acid (PUFA) content, the PUFA to SFA ratio, the mRNA expression of sterol regulatory element binding proteins-1c, and the activities of acyl-CoA oxidase 1 and acetyl-CoA synthetase (P < 0.05). Moreover, dietary 0.10% HMB decreased the activities of hydroxy-3-methylglutaryl-CoA synthase 1 and FAS in comparison to the control group (P < 0.05). Dietary 0.05% HMB decreased the contents of essential amino acids and nonessential amino acids (NEAA), and dietary 0.15% HMB decreased the NEAA content (P < 0.05). In summary, dietary 0.10% HMB supplementation had superior efficiency on lipogenesis in the breast muscle of broilers. However, dietary HMB supplementation, especially at the level of 0.05 and 0.15%, decreased meat nutritional values and the lipogenesis in leg muscles.

Correction to: Effects of HMB supplementation on hormonal adaptations following resistance training: a systematic review and meta‑analysis

Correction to: Effects of HMB supplementation on hormonal adaptations following resistance training: a systematic review and meta‑analysis

Effects of HMB supplementation on hormonal adaptations following resistance training: a systematic review and meta-analysis

Effects of HMB supplementation on hormonal adaptations following resistance training: a systematic review and meta-analysis