Smoking when you have a cold and fever can cause the respiratory tract to not flow smoothly and secretions to increase, causing the symptoms of a cold and fever to worsen and even a cough to appear. Smoking is harmful but not beneficial, and the occurrence and aggravation of many diseases are strongly related to smoking. Tobacco contains a large number of carcinogenic substances that can cause mutations in key genes in the body, the normal growth and control mechanisms are dysfunctional, leading to cellular carcinogenesis, causing the occurrence of malignant tumors, such as throat cancer, lung cancer, stomach cancer, esophageal cancer; smoking can lead to chronic obstructive pulmonary disease, adolescent asthma, increased incidence of tuberculosis; can damage cardiovascular, leading to atherosclerosis, is the biggest cause of coronary heart disease; also It can lead to a decline in fertility, causing premature fetal birth, stunted growth and other symptoms.