Obesity is divided into simple obesity and secondary obesity. Simple obesity refers simply to being overweight without any other primary diseases. Secondary obesity requires examination of certain conditions, such as hypothyroidism, which can lead to obesity, thus necessitating thyroid function tests; or Cushing's syndrome, which involves increased body weight due to excessive corticosteroid hormones produced by various causes, necessitating an examination of the cortisol rhythm and sometimes a dexamethasone suppression test, magnetic resonance imaging (MRI) of the pituitary, and CT scan of the adrenal glands; also conditions such as depression or psychiatric illnesses that can lead to weight gain, requiring corresponding psychiatric scales, among others. In addition to these tests, it is also necessary to consider the patient's clinical symptoms and then conduct targeted examinations based on these symptoms.