Self-reported health-related quality of life among regular multivitamin–mineral supplement users: a weighted pooled observational analysis of 2,600 adults from four Asia Pacific countries

Background Multivitamin-mineral (MVM) supplements are widely used across the Asia Pacific; however, real-world, validated patient-reported evidence on immune function, mental well-being and energy remains limited. The aim of the study is to evaluate the relationship between daily MVM consumption and quality of life using validated patient-reported outcomes (PROs) measures across pooled adult cohorts in the Asia-Pacific region and assess perceived immune and energy support among daily versus non-daily MVM users. Methods We conducted a pooled analysis of four cross-sectional surveys from Australia, South Korea, the Philippines, and Taiwan ( N = 2,600) among adult (20–65 years) existing users of the Centrum MVM supplement. The primary outcomes were validated PRO, including immune function (Immune Status Questionnaire [ISQ] < 6), mental well-being (WHO-5 Well-Being Index < 13) and energy level (SF-36 Vitality Scale). Secondary outcome included perceived immune and energy support. Data were harmonized and post-stratification weighted by location and sex. Survey-weighted multivariable logistic and linear regression models assessed associations between daily MVM use and PROs, adjusted for age, sex, income and location, with effect modification by age group. Results A higher proportion of daily MVM users reported agreement that MVM supplementation supports immunity (85.4% vs. 81.7%) and energy (84.8% vs. 79.5%). Differences across the full response distributions were statistically significant ( p < 0.001). For immune support, adults 40 years and older showed significantly higher agreement (85.8% vs. 82.8%, p < 0.001), while for energy support, daily use was associated with higher agreement across all age groups, particularly those under 40 years (87.4% vs. 81.5%, p = 0.005). These perceived benefits were consistent with findings from PROs: most users reported normal immune function (ISQ ≥ 6), and daily MVM use was associated with lower odds of reduced immune function (odds ratio [OR] 0.79, 95% CI 0.64–0.98) and poor mental well-being (OR 0.72, 95% CI 0.58–0.89), as well as higher Vitality Scale score (adjusted mean difference 3.29 points, 95% CI 1.91–4.68). Associations were generally consistent across age subgroups. Item-level analyses showed more frequent endorsement of positive well-being and perceived energy levels among daily users. Conclusion Daily MVM supplement use in Asia Pacific cohorts was associated with greater perceived health benefits, better well-being, and perceived energy levels, supporting its relevance in real-world settings.