Background: Self‑care activities related to diet, physical activity, foot care, and blood sugar monitoring in Type 2 diabetes mellitus (T2DM), besides traditional doctor‑centered care is essential. Hence, the study was undertaken to find the prevalence of nonadherence to dietary practices among patients with T2DM, its associated factors and to study the association of nonadherence with body mass index (BMI). Methods: The community‑based cross‑sectional study was carried out among 400 participants with T2DM aged ≥ 18 years in urban Bangalore. Dietary adherence was assessed using The Summary of Diabetes Self‑care Activities Questionnaire and anthropometric measurements were made to calculate BMI. Results: Of the total, 207 (51.8%) were ≥ 60 years, 211 (52.8%) were females and 377 (94.3%) were on oral hypoglycemic agents. Calories were unrestricted in 62.7%, fruits and vegetables were not consumed by 68.8%, and overall, 83.5% were nonadherent to diet. Conclusion: Education and marital status can affect a diabetic individual's diet adherence and hence it is necessary to focus on individuals who are likely to be nonadherent by giving them simple understandable instructions to follow and enabling them with wider variety of food and recipe options. Dislike to food in the diet plan contributed majorly to diet nonadherence and having individualized dietary options with the help of food exchange lists and involving nutritionists in diet planning may help overcome food aversions ensuring better adherence to diet. Creating awareness about self‑care among people with T2DM, ensuring strict adherence to diet at every follow‑up visit to the health‑care professional is required to prevent complications of diabetes.