What does it mean to have a high hemoglobin level?

Apr 21, 2022 Source: Cainiu Health
Disease description:

Today, during a physical examination, I found that my hemoglobin level is elevated. I would like to know: What does it mean when hemoglobin is high?

Doctor's answer (1)
Dr. Li Man
Elevated hemoglobin levels may result from either physiological or pathological factors. Physiological causes include excessive sweating, intense physical exercise, or significant emotional fluctuations, which can transiently increase hemoglobin concentration; typically, this elevation resolves spontaneously as the body recovers. However, pathological conditions—such as increased erythropoietin production or reduced plasma volume—can also lead to elevated hemoglobin levels.