For diabetics, the real threat is the complications caused by diabetes, especially the common complications like diabetic foot, diabetic retinopathy, diabetic nephropathy, etc. which can cause death and disability, are even more frightening for diabetics. It can be said that the reason why diabetics have to actively control sugar is mostly to prevent these complications. However, despite this, most diabetics using medical therapy are unable to avoid diabetic complications. Fortunately, weight reduction metabolic surgery has been developed over decades and has achieved clear results in the treatment of diabetes. Patients who are eligible for the procedure can basically be freed from drug dependence and achieve reversal with perfect postoperative management, and they do not have to worry about late complications as they do with medical therapy. So, is weight loss metabolic surgery still treatable for those who have already developed complications from diabetes. Generally speaking, diabetic patients who have already developed complications are in a serious condition, and one of the requirements for weight loss metabolic surgery is that the diabetic patient’s condition cannot be too serious and needs to have a certain level of insulin secretion, and if the patient does not meet this condition, it is difficult to achieve the desired effect even if the surgery is done. And for the complications that have already appeared, weight loss metabolic surgery may not be able to provide effective treatment. The effect of weight loss metabolic surgery is to help patients to control their blood sugar within a healthy range. If the complications that are not able to improve naturally weight loss metabolic surgery is also difficult to play too much of a therapeutic effect, so patients need to take corresponding methods of treatment again. In order to prevent complications, it is best for diabetic patients to undergo surgery as soon as possible, and the therapeutic effect of weight loss metabolic surgery will become less and less effective as the disease progresses.