Effects of oral supplementation of β -hydroxy-β -methylbutyrate on muscle mass and strength in individuals over the age of 50: a meta-analysis

Abstract

Background: β-Hydroxy β-Methylbutyrate (HMB) has shown potential in improving muscle protein turnover, which may be important for preventing muscle degradation in aging populations. The aim of this meta-analysis is to clarify the impact of HMB oral supplementation on muscle-related indicators and discover the interaction between dosage and duration. The findings will provide a scientific basis for the use of HMB oral supplementation in the management of muscle attenuation.

Methods: A computer systems-based search for articles of randomized controlled trial (RCT) in the PubMed, Cochrane Library, Web of Science, ScienceDirect, EBSCO English databases and China Journal Full-Text Database (CNKI), Wan Fang Chinese databases, was conducted up to October 2023. Data were pooled using weighted mean difference (WMD) and 95% confidence intervals (95% CI).

Results: A total of 21 RCTs were included, involving 1935 participants, all of them were > 50 years old. Results showed a positive impact of HMB oral supplementation in improving muscle mass (appendicular skeletal muscle mass: WMD = 1.56 kg, 95% CI: 0.03-3.09 kg and lean mass: WMD = 0.28 kg, 95% CI: 0.16-0.41 kg), strength (handgrip strength: WMD = 0.54 kg, 95% CI: 0.04-1.04 kg and five-time chair stand test: WMD = -0.73 s, 95% CI: -1.35, -0.11 s), and physical function (gait speed: WMD = 0.06 m/s, 95% CI: 0.01-0.10 m/s). Subgroup analysis revealed that the effect of a dosage of 3 g/d had significant improvement, and the effect of supplementation duration lasting > 12 weeks had significant improvement, and a dosage of 3g/day for more than 12 weeks was recommended.

Conclusion: HMB oral supplementation can improve muscle mass, strength, and physical function. We recommend to implement supplementation at a dosage of 3 g for a duration exceeding 12 weeks to achieve optimal benefits.

Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/login, identifier 42024518958.

Keywords: dosage; duration; function; mass; metaanalysis; muscle; strength; β-Hydroxy-β-methylbutyrate.

FIGURE 1

Flowchart illustrating various phases of the search and study selection according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.

FIGURE 2

Risk-of-bias proportion for all studies.

FIGURE 3

Risk-of-bias summary for all studies.

FIGURE 4

Forest plot of the effect of β-Hydroxy β-Methylbutyrate (HMB) on appendicular skeletal muscle mass (ASMM). The area of each square is proportional to the study’s weight in the meta-analysis. The vertical line and diamond indicate the overall measure of the effects and confidence intervals, respectively.

FIGURE 5

Forest plot of the effect of HMB on lean mass (LM). The area of each square is proportional to the study’s weight in the meta-analysis. The vertical line and diamond indicate the overall measure of the effects and confidence intervals, respectively.

FIGURE 6

Forest plot of the effect of HMB on handgrip strength. The area of each square is proportional to the study’s weight in the meta-analysis. The vertical line and diamond indicate the overall measure of the effects and confidence intervals, respectively.

FIGURE 7

Forest plot of the effect of HMB on five-time chair stand test. The area of each square is proportional to the study’s weight in the meta-analysis. The vertical line and diamond indicate the overall measure of the effects and confidence intervals, respectively.

FIGURE 8

Forest plot of the effect of HMB on gait speed. The area of each square is proportional to the study’s weight in the meta-analysis. The vertical line and diamond indicate the overall measure of the effects and confidence intervals, respectively.

FIGURE 9

Forest plot of the effect of HMB on 6-min walk test (6MWT). The area of each square is proportional to the study’s weight in the meta-analysis. The vertical line and diamond indicate the overall measure of the effects and confidence intervals, respectively.

FIGURE 10

ASMM, LM, handgrip strength, five-time chair stand test, gait speed, and 6MWT bias funnel plot.

FIGURE 11

Handgrip strength, gait speed, five-time chair stand test, and 6MWT virtual pruning funnel plot.