Type 2 diabetic patients who do not take injections or medications and have poor glycemic control may gain weight, but they may also lose weight. Patients with type 2 diabetes mellitus who do not take injections or medications, do not engage in active dietary control and exercise, and have untimely glycemic control may have insulin resistance due to factors such as obesity caused by a poor lifestyle and increasing age, which does not effectively promote the uptake of glucose by the tissues or inhibit the output of glucose from the liver, leading to disturbances in the metabolism of carbohydrates, fats, and other metabolic disorders. As a result, it may be possible for a patient with type 2 diabetes to have poor glycemic control without injections or medication, and may gain weight. If type 2 diabetes mellitus is suspected, you should seek medical advice and targeted treatment under the guidance of your doctor to avoid delays.