Reference Values for Biochemical Analytes in An Iranian Population: The Tehran Lipid and Glucose Study

Abstract

Context: Reference values (RVs) are essential tools for medical decision-making, used to interpret an individual’s health status and playing a crucial role in patient care. In addition to age, sex, and inherent biological variability, multiple determinants, including ethnicity, genetic background, dietary habits, environmental factors, and lifestyle, which vary across different populations, play a significant role in the establishment of RVs. Thus, each population requires its own RVs to ensure their effectiveness. Evidence Acquisition: In this review, we summarize RVs reported in the Tehran Lipid and Glucose Study (TLGS) between 2010 and 2026, covering 20 analytes measured in apparently healthy participants, including 16 in adults and 4 in pediatrics. Relevant TLGS publications were identified, and their findings were compared with corresponding international data. Results: RVs were provided for 20 parameters, classified into three categories: (1) Glucose, insulin, insulin resistance/sensitivity indices, and lipid profile; (2) thyroid function tests [thyroid-stimulating hormone (TSH) and free thyroxine (T4)] and autoimmunity [thyroid peroxidase antibody (TPO-Ab)]; (3) other variables, including creatinine and minerals (serum zinc and magnesium), and serum nitric oxide metabolites. Conclusions: The RVs determined by the TLGS provide a population-specific framework for the Iranian population and may serve as a more accurate tool for classification and clinical interpretation than common global RVs. These data emphasize the importance of developing localized RVs to enhance diagnostic precision and improve population health outcomes.