Association of Dietary Acid Load with Metabolic Syndrome-Related Parameters Following Eating Habit Modification in Korean Adults

<b>Background/Objectives:</b> This study examined the association between dietary acid load (DAL) and metabolic syndrome (MetS)-related parameters in Korean adults undergoing eating habit modification. <b>Methods:</b> Forty-eight Korean adults (≥19 years) with at least one MetS risk factor were recruited via public advertisement. Anthropometric and biochemical parameters, Nutrition Quotient (NQ) scores, and nutrient intake were assessed. The DAL was calculated and expressed as the potential renal acid load (PRAL) and the net endogenous acid production (NEAP). <b>Results:</b> Forty participants completed the 8-week intervention. Overall improvements were observed in total and domain-specific NQ scores, along with improvements in body composition, blood pressure, and glycemic parameters. Among all participants, the mean DAL scores did not change significantly after FDR correction, although the NEAP showed a modest non-significant decrease. Baseline PRAL and NEAP values did not differ between participants with and without MetS risk improvement. At weeks 4 and 8, DAL indices tended to decrease in the improved group and increase in the non-improved group, with a significant between-group difference observed only for the 8-week change in NEAP after FDR correction. While no significant associations were detected at baseline after FDR adjustment, cross-sectional associations between DAL indices and adiposity-related parameters were observed at week 8, particularly when DAL was expressed as NEAP. However, change-to-change analyses did not remain significant after FDR correction. <b>Conclusions:</b> In this exploratory study, DAL levels, especially NEAP, were associated with anthropometric and metabolic status at week 8; however, the absence of significant change-to-change correlations limits causal interpretation. Larger randomized controlled trials are needed to determine whether modification of DAL independently contributes to metabolic improvement (Trial registration number: KCT0011528).