Association of mitragynine levels with lipid profiles in regular kratom (Mitragyna speciosa) users

• Kratom users showed lower LDL, urea, creatinine, and higher eGFR than non-users. • Serum mitragynine correlated negatively with LDL and TG levels. • Most users consumed kratom for health, often > 21 leaves daily in concentrated brews. Kratom ( Mitragyna speciosa ) is widely consumed in Southeast Asia for both medicinal and recreational purposes, yet its impact on human health remains unclear. This study examined sociodemographic factors, consumption patterns, serum mitragynine (MG) levels, and clinical chemistry parameters among 90 male participants from the Putussibau District, West Kalimantan, Indonesia. Participants were categorized into kratom users (n = 64) and non-users (n = 26). The majority of users indicated that they consumed kratom for health-related reasons, most commonly for 2–5 years, and nearly half reported daily intake exceeding 21 leaves. Serum MG concentrations were significantly higher among users than non-users, although no associations were observed with duration or intensity of consumption. Clinical chemistry analysis revealed that kratom users had lower levels of LDL, BUN, urea, and creatinine, alongside higher eGFR values, while no significant differences were detected in liver enzymes, glucose, HDL, triglycerides, or inflammatory markers. Notably, serum MG was negatively correlated with LDL and triglyceride levels. Stratified analysis indicated that long-term use was associated with favorable hepatic and lipid profiles, suggesting possible adaptive metabolic responses, whereas higher daily intake produced mild, subclinical elevations in liver and renal markers. Additionally, systemic inflammation, reflected by increased hsCRP and IL-6, was linked to self-reported anxiety, highlighting a potential peripheral mechanism connecting kratom use to central nervous system (CNS) effects. Overall, these findings suggest that regular kratom use may elicit adaptive physiological changes with minimal biochemical perturbation at moderate intake levels. Further longitudinal and mechanistic studies are warranted to clarify causal pathways and long-term health implications of kratom use.