Introduction <p>Type 2 Diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by insulin resistance and hyperglycemia, often preceded by latent metabolic disruptions. Early detection of metabolic alterations can facilitate timely intervention to delay or prevent T2DM onset. Metabolic profiling offers a useful tool to identify novel biomarkers and early metabolic alterations before clinical manifestations.</p> Objective <p>This study aimed to identify early metabolic alterations and potential biomarkers predictive of T2DM in a cohort of healthy normoglycemic participants over a six-year follow-up.</p> Methods <p>A cohort of 94 healthy participants, both men and women aged 18–40, was studied at six-year intervals. Clinical and biochemical parameters were measured, and LC/MS/MS-based untargeted metabolomics analysis of plasma was performed at both baseline and follow-up.</p> Results <p>At follow-up, 9 participants developed T2DM, 51 had prediabetes, and 34 remained normoglycemic. Increasing insulin resistance and elevated future T2DM risk were observed in both the prediabetes and normoglycemia groups. Metabolomics analysis identified phosphatidylethanolamine (PE) (20:3_18:0), 3beta,7alpha-dihydroxy-5-cholestenoate, and tridecanoic acid—as having good predictive capacity for future T2DM risk at baseline with alterations in PE (20:3_18:0), and tridecanoic acid persisting at follow-up.</p> Conclusion <p>The study highlights the potential of metabolomics in identifying early metabolic predictors of T2DM, emphasizing the need for early interventions in healthy normoglycemic young adults.</p>