Background/Objectives Oxidized low‐density lipoprotein (oxLDL) has emerged as a promising biomarker of oxidative burden and cardiovascular risk. This study is aimed at evaluating the effect of ubiquinol supplementation, a potent lipophilic antioxidant, on oxLDL levels in prediabetic patients. Methods This was a prospective, randomized, double‐blinded, placebo‐controlled pilot study of 20 adults with impaired fasting plasma glucose (FPG). Participants were randomized to receive either ubiquinol (100 mg/day) or placebo for 12 weeks. Plasma oxLDL levels were measured at baseline and Week 12. Results After 12 weeks, the ubiquinol group demonstrated a significant within‐group reduction in plasma oxLDL compared with baseline ( p = 0.049), whereas no significant change was observed in the placebo group ( p = 0.237). No adverse events were reported. Conclusions Daily ubiquinol (100 mg/day) for 12 weeks was associated with a significant within‐group decrease in plasma oxLDL among prediabetic participants; however, the between‐group difference versus placebo was not significant. Trial Registration Thai Clinical Trials Registry: TCTR20250512008
Leaovitavat et al. (Thu,) studied this question.