Diabetics are most effectively stabilized when they are at their ideal body weight. Pets that are very overweight (obese) may have “insulin resistance” meaning that insulin therapy is less effective and higher doses a required.
Weight loss should be gradual. Overweight dogs should be fed 2/3 of the recommended daily allowance of a suitable diet until they have reached their ideal body weight. Your veterinary surgeon or veterinary nurse will help you calculate the ideal body weight and food requirements for your diabetic dog and monitor its weight loss.