Hemoglobin is always high but not felt, it may be physiologically high, mainly seen in drinking too little water, sweating a lot, plateau area, etc.. 1. Drinking too little water or sweating too much: excessive loss of body fluids in the body, the blood will be relatively concentrated, which will lead to higher hemoglobin concentration in the blood. 2. Living in plateau areas: oxygen is scarce in plateau areas, leading to lack of oxygen in the tissues of the body, and the long-term low oxygen environment, resulting in high hemoglobin. In addition, there are a number of diseases that can easily lead to increased hemoglobin, such as severe vomiting, diarrhea, chronic heart disease, tumors and other diseases lead to. The symptoms of elevated hemoglobin are masked due to other disease symptoms. If the hemoglobin is high all the time, it is recommended to go to the hospital for further examination in time, and the disease cannot be diagnosed based on one test result alone.