This is a prospective, multicenter, real-world study conducted in Bangladesh to assess the effectiveness and safety of Tirzepatide compared to structured lifestyle interventions, including dietary modifications and exercise, in obese adults with or without Type 2 Diabetes Mellitus (T2DM).

The study aims to determine whether treatment with Tirzepatide results in superior weight reduction outcomes compared to lifestyle-based approaches. Adult participants (≥18 years) with a body mass index (BMI) ≥25 kg/m² and no prior exposure to GLP-1 receptor agonists will be enrolled at the discretion of the treating physician. Eligible participants will receive either once-weekly Tirzepatide or participate in lifestyle intervention programs aligned with standard clinical care.

Inclusion Criteria:

• Adult patients of both sexes, aged ≥18 years.
• Body mass index (BMI) ≥25 kg/m².
• Naïve to glucagon-like peptide-1 receptor agonist (GLP-1 RA) therapy.
• Self-reported stable body weight (change ≤5 kg) over the past 3 months.

Exclusion Criteria:

• Diagnosis of diabetes other than Type 2 Diabetes Mellitus.
• History of chronic or acute pancreatitis.
• Presence of acute medical conditions, including acute hepatitis, myocardial infarction, stroke, heart failure, febrile illness, or acute diarrheal disease.
• Evidence of significant, uncontrolled endocrine disorders (e.g., Cushing's syndrome, thyroid disorders, adrenal insufficiency, congenital adrenal hyperplasia).
• History or presence of malignancy.
• Active gallbladder disease.
• Female participants who are pregnant, breastfeeding, planning pregnancy, or of childbearing potential, not using adequate contraceptive methods.
• Prior or planned surgical treatment for obesity.
• Use of weight-loss products (including prescription medications, over-the-counter drugs, or herbal preparations) within 3 months prior to screening.

The study population will include adult males and females aged 18 years and older who are clinically diagnosed with obesity, with or without Type 2 Diabetes Mellitus. Eligible participants are those who have been prescribed Tirzepatide (2.5 mg, 5 mg, or 7.5 mg) administered subcutaneously once weekly, or who are undergoing structured lifestyle interventions involving extensive exercise and dietary control. Only patients meeting all inclusion criteria and none of the exclusion criteria will be enrolled in the study.

The individual participant data (IPD) from this study will not be shared with other researchers due to institutional and regulatory restrictions related to patient confidentiality, data protection regulations, and the absence of a pre-approved data-sharing framework. Additionally, the study is designed as a real-world investigation without predefined provisions for external IPD access. Any future sharing of data will require separate ethical approval and patient re-consent, which are not within the current study's scope.