I-STARCH Study Protocol: A Multicentric Observational Study of Macronutrient Intake in Adults With and Without Type 2 Diabetes Mellitus in India

Background: Type 2 diabetes mellitus (T2DM) is a significant public health concern in India, driven by rapid urbanization, increased consumption of ultra-processed foods, and changing dietary habits. These factors necessitate updated, real-world data to guide dietary interventions and public health strategies. Aims: This study aims to evaluate macronutrient intake as a percentage of total energy consumption in adults with and without T2DM. Secondary objectives include assessing dietary patterns, meal frequency, water intake, and associations with biochemical markers such as glycosylated hemoglobin (HbA1c), fasting blood glucose (FBG), postprandial blood glucose (PPBG), and lipid profiles. Methods: The I-STARCH study (Indian Study to Assess Real World CarboHydrate Consumption) employs a multicentric, cross-sectional observational design across 33 healthcare centers in India, targeting 1,000 participants. Data collection includes a structured 3-day dietary recall, demographic and clinical data from authenticated medical records, and standardized case report forms (CRFs). Statistical analysis will examine dietary patterns, their relationship with metabolic outcomes, and subgroup differences (e.g., urban vs. semi-urban). Expected Outcomes: The study will provide critical insights into contemporary dietary behaviors, facilitating personalized dietary recommendations and contributing to strategies for effective diabetes prevention and management. Summary: The I-STARCH study explores how diet affects blood glucose and lipid levels in Indian adults with and without Type 2 diabetes, aiming to guide personalized nutrition strategies.