The Role of Oil‑Based Diets on the Development of Diabetes in the Indian Population

India faces a rapidly growing burden of type 2 diabetes mellitus (T2DM), driven by a complex interplay of genetic, dietary, and lifestyle factors. Among dietary contributors, the type and quality of edible oils used in cooking have emerged as important modulators of metabolic risk. Traditional Indian oils—such as mustard, sesame, and groundnut—differ significantly in fatty acid composition from widely adopted refined oils like sunflower and soybean oil. Evidence from epidemiological, clinical, and experimental studies in India suggests that high intake of oils rich in omega-6 polyunsaturated fats, trans fats, or saturated fats may worsen insulin resistance, promote inflammation, and contribute to adiposity and dyslipidemia—key drivers of diabetes. Indian populations may be particularly vulnerable due to genetic predisposition, high visceral fat deposition, low physical activity, and a dietary shift towards processed foods, refined carbohydrates, and industrial oils. Observational studies (e.g., in Chennai and rural South India) report higher metabolic syndrome prevalence among users of refined oils compared to traditional oils. Mechanistically, oil quality, cooking practices (e.g., repeated heating), and fatty acid balance (n-6:n-3 ratio) appear to influence key pathways including insulin signaling, oxidative stress, and lipid metabolism. Despite compelling associations, evidence gaps remain, especially in long-term randomized trials and real-world cooking behavior. Public health responses must include promoting oils with healthier profiles (e.g., groundnut, sesame, mustard), reducing reuse and over-processing, improving dietary quality, and increasing awareness. With India’s high-risk phenotype and dietary transitions, oil choice represents a modifiable and impactful lever in diabetes prevention.