fig1

Figure 1. The natural history of T1D. The graph illustrates the progressive decline in pancreatic β cell function over time (yellow line), starting with the Preclinical Stage (Stage 1), where β cell autoimmunity is present without clinical symptoms. This is followed by Stage 2, characterized by IGT without overt diabetes, and culminates in Stage 3, where near-total β cell destruction results in symptomatic T1D. T1D: Type 1 diabetes; IGT: impaired glucose tolerance.