High blood sugar may be caused by the following reasons: First, caused by drinking alcohol. Drinking alcohol will reduce diet and increase satiety, but the absorption and metabolism of alcohol are faster and cannot maintain blood sugar level for a longer period of time, so it will cause blood sugar to rise. Second, caused by taking certain hormone drugs, certain hormone drugs such as prednisone, dexamethasone, etc., can make the blood sugar rise. Third, too much pressure, emotional and mental pressure is too heavy, the emotional ups and downs fluctuate too much, it will make the function of certain organs in the body can not play normally, causing the internal environment disorder, so that the blood sugar rises. Fourth, excessive obesity, too much diet will lead to obesity, and easily lead to elevated blood sugar. Fifth, improper diet, excessive intake, especially sweets and sugary drinks, making the sugar content in the human body significantly higher than the normal standard, but also the formation of fat in the blood increased, resulting in high blood sugar. Sixth, due to the reduction of exercise, if due to the sudden reduction of exercise, resulting in insulin can not effectively play a role, so blood sugar will also appear to rise. Seven, caused by some diseases: diabetes, pheochromocytoma, Cushing’s syndrome, growth hormone tumor, etc.