A 12-Week Randomized Controlled Trial of Nutrition and Exercise Education with Dietary Supplementation for Sarcopenia Prevention in Korean Baby Boomers

<b>Background/Objectives</b>: Sarcopenia is a major public health concern, and early preventive strategies in midlife are increasingly emphasized. The goal of this study was to evaluate the effectiveness of a 12-week lifestyle intervention that included nutrition education, exercise education, and dietary supplementation in Korean baby boomers. <b>Methods</b>: This single-blind, randomized controlled trial included 42 Korean baby boomers born between 1955 and 1963. Participants were randomly assigned to one of three groups: (1) nutrition and exercise education plus dietary supplementation (DiExSp), (2) nutrition and exercise education only (DiEx), or (3) control. The intervention was delivered online, and the DiExSp group additionally received a daily supplement containing protein, vitamins, and minerals. Primary outcomes included dietary intake, body composition, physical function, and fasting blood biomarkers. Nonparametric tests and effect size calculations were performed using SAS version 9.4. <b>Results</b>: A total of 31 participants completed the study. The results showed significant increases in protein and micronutrient intake (<i>p</i> < 0.05), with large effect sizes in the DiExSp group. Handgrip strength showed improvement in both the DiExSp and DiEx groups (DiExSp: <i>p</i> = 0.027, <i>r</i> = 0.63; DiEx: <i>p</i> = 0.020, <i>r</i> = 0.73), while no changes were observed in other physical parameters. HbA1c levels showed a significant decrease in the DiExSp group compared to the control (<i>p</i> < 0.05, ε² = 0.01). No significant differences were observed for other biomarkers. <b>Conclusions</b>: A 12-week intervention combining dietary supplementation with education resulted in improved dietary intake, muscle strength, and glycemic control. However, most effects were confined to within-group changes. Between-group differences were minimal, and effect sizes were small. These findings provide preliminary evidence that lifestyle intervention strategies may contribute to sarcopenia prevention in midlife adults.