HMB

What does the research say?

Research indicates that HMB supplementation can enhance muscle mass and strength, particularly when combined with resistance training [4] [26] . It is most effective in individuals who are new to exercise and the elderly, but can also benefit trained individuals undergoing high physical stress [4] . Several studies show that HMB improves muscle protein balance by both stimulating protein synthesis and reducing muscle protein breakdown [1] [4] [8] . In clinical populations with muscle wasting, HMB supplementation, often combined with other amino acids like arginine and glutamine, can lead to significant gains in lean body mass [13] . While some studies in athletes have shown mixed results, many indicate that HMB supplementation can improve strength, power output and lean muscle mass gains [26] . However, it is important to note that the positive effects of HMB on muscle growth are often seen when it is combined with exercise, particularly resistance training [4] [16] .

Gastrointestinal issues

Some studies reported minor gastrointestinal issues such as discomfort, but these were not severe [1] .

Decreased Glutamine Levels

Some studies have shown that HMB might lower the levels of glutamine, an important amino acid, in the body [9] .

Altered ATP Metabolism

Changes in energy production (ATP metabolism) have been noted in some studies, particularly in diabetic rats [9] .

[1] Effects of β-hydroxy β-methylbutyrate (HMB) supplementation on muscle mass, function, and other outcomes in patients with cancer: a systematic review.

This review examines the effects of HMB supplementation on muscle mass, function, and other outcomes in cancer patients. HMB was found to stimulate muscle protein synthesis and reduce breakdown. Studies showed it to improve muscle mass and function in cancer patients with minimal side effects.

[2] Adenomyosis: Mechanisms and Pathogenesis.

This review focuses on the mechanisms and pathogenesis of adenomyosis and does not include any data on HMB supplementation.

[3] Advances in muscle health and nutrition: A toolkit for healthcare professionals.

This article synthesizes the latest research advancements in muscle health and malnutrition, and their impact on immune function, and clinical outcomes. It provides a toolkit of illustrations and scientific information that healthcare professionals can use for knowledge translation. It addresses nutrition interventions to support anabolism, reduce catabolism and improve patient outcomes, including HMB.

[4] Beta-hydroxy-beta-methylbutyrate supplementation and skeletal muscle in healthy and muscle-wasting conditions.

This review examines the role of HMB in muscle protein turnover. HMB stimulates protein synthesis and decreases protein breakdown, leading to enhanced muscle hypertrophy, strength, and recovery. It is particularly effective in untrained individuals and those experiencing muscle wasting. It highlights that HMB does not have significant toxic effects.

[5] Dietary Supplements for Health, Adaptation, and Recovery in Athletes.

This review discusses several dietary supplements that may improve health, exercise adaptation, or recovery in athletes, including HMB. It notes that HMB does not consistently increase strength and/or lean mass, or reduce markers of muscle damage. It calls for further research on HMB and recovery from injury.

[6] Supplements with purported effects on muscle mass and strength.

This review examines various supplements purported to promote muscle hypertrophy and strength gains, or to prevent muscle wasting. However, it concludes that their effectiveness remains unclear.

[7] Nutritional interventions to improve muscle mass, muscle strength, and physical performance in older people: an umbrella review of systematic reviews and meta-analyses.

This umbrella review presents the results of the Working Group on Nutritional Interventions in the treatment of sarcopenia. It does not focus specifically on HMB, but it provides an overview of nutritional strategies to treat sarcopenia.

[8] Regulation of Skeletal Muscle Function by Amino Acids.

This review discusses the role of amino acids, including leucine and its metabolite HMB, in regulating skeletal muscle function. HMB activates mTORC1, which leads to increased protein synthesis and reduces muscle atrophy. Endogenous HMB, however, does not significantly contribute to muscle anabolism.

[9] Side effects of amino acid supplements.

This review discusses the side effects of amino acid supplements, including HMB. While HMB is generally well-tolerated, some studies have observed decreased glutamine levels and altered ATP metabolism, particularly in diabetic rats.

[10] Protein Recommendations for Weight Loss in Elite Athletes: A Focus on Body Composition and Performance.

This review discusses protein recommendations for weight loss in elite athletes, it touches on the use of protein supplements, branched-chain amino acids (BCAA), β-hydroxy β-methylbutyrate (HMB), and other dietary supplements with weight loss claims, but does not have specific conclusions.

[11] Inhibition of prostaglandin-degrading enzyme 15-PGDH rejuvenates aged muscle mass and strength.

This clinical study focuses on the inhibition of 15-PGDH and its effects on muscle mass and strength in aged mice. It does not mention HMB.

[12] Prevalence of and interventions for sarcopenia in ageing adults: a systematic review. Report of the International Sarcopenia Initiative (EWGSOP and IWGS).

This review examines the prevalence of and interventions for sarcopenia in aging adults. It notes HMB as a metabolite of leucine that has some effects on muscle mass and function, with studies showing improvements in muscle strength and physical performance, though the evidence is limited.

[13] Nutrition interventions to treat low muscle mass in cancer.

This review investigates the use of nutritional interventions to treat low muscle mass in cancer. HMB can mitigate muscle loss in cancer and improve body composition in other clinical populations. HMB, when combined with other amino acids, can induce significant gains in lean mass in patients with advanced cancer. The effects of HMB alone on cancer-associated muscle wasting have not been extensively studied.

[14] Skeletal Muscle Regulates Metabolism via Interorgan Crosstalk: Roles in Health and Disease.

This review discusses the role of skeletal muscle in energy and protein metabolism, the consequences of muscle loss, and strategies to restore muscle mass, strength and function. It notes that leucine and its metabolite, HMB, can improve muscle function.

[15] Glucocorticoid-induced skeletal muscle atrophy.

This review focuses on the mechanisms involved in glucocorticoid-induced muscle atrophy and does not contain information about HMB.

[16] Current Nutritional and Pharmacological Approaches for Attenuating Sarcopenia.

This review discusses current nutritional and pharmacological approaches to address sarcopenia, focusing on HMB. HMB stimulates protein synthesis and reduces muscle breakdown. Supplementation with HMB can increase lean body mass, and may improve muscle performance when combined with other nutrients and exercise.

[17] The role of leucine and its metabolites in protein and energy metabolism.

This review discusses the role of leucine and its metabolites in protein and energy metabolism, highlighting that leucine stimulates protein synthesis. HMB and α-KIC are leucine metabolites that can increase protein synthesis, inhibit protein degradation, and regulate energy homeostasis.

[18] Effects of Beta-Hydroxy-Beta-Methylbutyrate Supplementation on Elderly Body Composition and Muscle Strength: A Review of Clinical Trials.

This review examines the effects of HMB supplementation on body composition and muscle strength in the elderly. HMB has anabolic and anticatabolic properties, stimulating tissue repair and protein synthesis, which can help mitigate age-related muscle loss.

[19] Tissue Stem Cells: Architects of Their Niches.

This review focuses on the role of tissue stem cells in maintaining tissue homeostasis and regeneration, particularly in skin and muscle tissues. It does not discuss HMB.

[20] New strategies in sport nutrition to increase exercise performance.

This review discusses emerging strategies in sports nutrition to increase exercise performance, noting that novel compounds, including HMB, may promote or attenuate skeletal muscle adaptations. It highlights that HMB needs to be further researched.

[21] Leucine supplementation and intensive training.

This review discusses the role of leucine in protein metabolism and the potential benefits of its supplementation. It mentions that HMB supplementation has resulted in increased fat-free mass and strength, accompanied by decreased muscle proteolysis and lower plasma levels of enzymes indicating muscle damage.

[22] Effect of Ten Weeks of Creatine Monohydrate Plus HMB Supplementation on Athletic Performance Tests in Elite Male Endurance Athletes.

This study examined the effect of combined creatine and HMB supplementation on athletic performance. Creatine improves performance by enhancing ATP production, while HMB may help with muscle protein synthesis. The study found that this combination did not lead to changes in muscle mass but did improve aerobic power.

[23] The Effects of Protein and Supplements on Sarcopenia in Human Clinical Studies: How Older Adults Should Consume Protein and Supplements.

This review discusses the role of protein and supplements in managing sarcopenia. HMB, derived from leucine metabolism, has been shown to improve muscle strength and quality in the elderly, reduce muscle degradation, and prevent muscle mass decline during bed rest. The review indicates that 2-3 grams daily are safe with no adverse effects.

[24] Effects of Beta-Hydroxy-Beta-Methylbutyrate Supplementation on Older Adults with Sarcopenia: A Randomized, Double-Blind, Placebo-Controlled Study.

This study is a clinical trial that evaluates the effect of HMB intervention on muscle strength, physical performance, body composition, and inflammatory factors in older adults with sarcopenia.

[25] Nutritional Strategies to Optimize Performance and Recovery in Rowing Athletes.

This review discusses nutritional strategies for rowing athletes, including the use of HMB. HMB increases muscle mass and improves muscle recovery, and may also promote mitochondrial biogenesis.

[26] Mechanism of Action and the Effect of Beta-Hydroxy-Beta-Methylbutyrate (HMB) Supplementation on Different Types of Physical Performance - A Systematic Review.

This systematic review examines the mechanism of action and effects of HMB supplementation on physical performance. HMB enhances sarcolemma integrity, inhibits protein degradation, decreases cell apoptosis, and increases protein synthesis. HMB shows positive effects on aerobic capacity in endurance athletes and improvements in strength and muscle mass in resistance trained athletes.

[27] Readmission and mortality in malnourished, older, hospitalized adults treated with a specialized oral nutritional supplement: A randomized clinical trial.

This study is a randomized clinical trial that does not focus specifically on HMB, but it examines the impact of specialized oral nutritional supplements on readmission and mortality rates in malnourished, older, hospitalized adults.

[28] Hormones and Sarcopenia.

This review discusses the role of hormones in sarcopenia. It notes that testosterone is the central hormone involved and that, at present, the treatment of sarcopenia involves resistance exercise, leucine enriched essential amino acids or hydroxymethylbutyrate, and vitamin D replacement.

[29] Time-restricted feeding plus resistance training in active females: a randomized trial.

This study examined the effects of time-restricted feeding (TRF) combined with resistance training and HMB supplementation in active females. HMB did not definitively improve outcomes compared to TRF without HMB.

[30] Mapping ongoing nutrition intervention trials in muscle, sarcopenia, and cachexia: a scoping review of future research.

This scoping review maps ongoing nutrition intervention trials focusing on muscle, sarcopenia, and cachexia, including the use of HMB. HMB is believed to enhance muscle protein synthesis and reduce muscle protein breakdown, particularly in clinical populations. HMB is often used in combination with other nutrients to enhance its effects.