The harm of one cold and one hot is reflected in the following points: 1, for the digestive system, especially the stomach, eating hot and cold alternately will stimulate the stomach, so that the stomach can not adapt to the stomach inflammation, especially prone to indigestion, diarrhea, etc. 2, for the stimulation of blood vessels, hot and cold alternately can lead to patients with reduced vascular adaptation, very easy to induce chronic diseases or acute cerebral thrombosis, myocardial infarction, and even acute stroke, etc. 3, a hot and cold stimulation of the immune system will cause damage to the body, especially the nerve endings such as hands and feet, constantly hot and cold stimulation is very easy to induce rheumatism and wind-like. 3, a cold and hot stimulation for the immune system will cause damage, so that the body is at a loss, especially nerve endings such as hands and feet, hot and cold stimulation is very easy to induce rheumatism and rheumatoid immune diseases, this disease once appeared, will cause great harm to the human body, and can not be cured, will be harmful for life.