Whether a cold affects blood sugar varies according to each person’s situation, and the degree of impact also varies. The general population has no significant effect on blood sugar after a cold, while the diabetic population is prone to higher blood sugar. 1. General population: After a cold, the general population has no significant effect on blood sugar. Because insulin is secreted on demand in normal people, the body’s blood sugar rises, insulin is secreted immediately, and the reserve function of insulin is good, generally will not cause significant fluctuations in blood sugar, blood sugar will remain within the normal range. The general fasting blood sugar is generally 3.9-6.1mmol/L, and the 2-hour postprandial blood sugar does not exceed 7.8mmol/L. So the general population can drink sugar-containing cold and fever reducer after the cold, etc. 2. Diabetic people: diabetic people and people with abnormal glucose tolerance and impaired fasting blood sugar may induce an increase in blood sugar during the cold. Because the cold itself is a state of stress, it will increase the secretion of glucose hormones in the body, including adrenocorticotropic hormone, epinephrine, norepinephrine, etc., may increase the secretion of these hormones will affect the body’s blood glucose metabolism, is the main glucose hormone, and the body to lower blood sugar only insulin, diabetes patients insulin can not play a good role, easily lead to disorders of glucose metabolism. During the period of cold and flu, if diabetic patients have poor appetite, they should reduce the use of hypoglycemic drugs as well as insulin, otherwise hypoglycemia will easily occur. Elderly people and diabetic patients who have a cold should rest more, be less active, ensure normal diet intake, and go to the hospital if necessary.