Insulin and Weight Gain

Insulin is a life-saving medicine for diabetes, but it can cause weight gain as it helps the body store energy. This does not mean you should avoid insulin; your doctor can adjust your plan to limit weight gain. Eating consistently and staying active help keep your weight stable.

Insulin promotes anabolic fat storage, reduces glucosuria, and can stimulate appetite, with typical weight gain of 2-4 kg in the first year of therapy. Strategies to limit gain include using basal-only regimens where appropriate, combining insulin with metformin or GLP-1 receptor agonists, and structured lifestyle support. Insulin doses should be down-titrated when GLP-1 therapy is added to avoid hypoglycaemia.

Fear of weight gain is a common reason patients delay starting insulin. Our clinic provides diabetes and weight management together, so patients get balanced advice on how medications affect weight.