The causes of high high-density cholesterol are more complicated. First of all, it may be caused by improper diet. If you consume too much high-fat and high-calorie stuff, it will lead to high HDL cholesterol in your body, so you need to pay attention to your diet, eat a light diet and try to eat less greasy food. Secondly, high high-density cholesterol may be caused by abnormal liver absorption. Abnormal liver absorption usually leads to abnormal synthesis and secretion of high-density cholesterol, which makes the symptoms of high high-density cholesterol appear, so you should go to the hospital for examination in time and take corresponding drugs for treatment under the guidance of doctors. High high-density cholesterol may be caused by abnormal metabolism, which usually requires testing of the body and consumption of foods and drugs that promote accelerated metabolism.