Efforts to improve glycaemic control in people with diabetes have encouraged more intensive therapeutic approaches. Hypoglycaemia is a risk associated with insulin therapy and a further consequence of intensified treatment is unwanted weight gain. The introduction of the long-acting insulin analogues, glargine and detemir, has provided a circulating insulin profile more reminiscent of normal basal insulin. This has allowed insulin dose escalation with a reduced risk of hypoglycaemia. The current study investigates the effect of switching treatment to insulin detemir in patients who had gained weight on insulin glargine therapy. Two months of treatment with insulin detemir did not alter glycaemic control or insulin dosage, but body weight was significantly reduced in patients with type 1 (p<0.05) and type 2 (p<0.005) diabetes. Br J Diabetes Vasc Dis 2008; 8: 183—186