HG in BP (blood pressure) refers to mercury. More specifically, it stands for millimeters of mercury (mmHg), which is the unit used to measure blood pressure.
Blood pressure measurements are typically expressed as two numbers, such as 120/80 mmHg. This reading represents:
- Systolic pressure: The top number represents the pressure in your arteries when your heart beats (contracts).
- Diastolic pressure: The bottom number represents the pressure in your arteries when your heart rests between beats.
The "mmHg" unit indicates that blood pressure is measured by how high the pressure in your arteries can raise a column of mercury. Although mercury sphygmomanometers (blood pressure monitors) are becoming less common due to concerns about mercury toxicity, the mmHg unit remains the standard unit of measurement for blood pressure, even with digital devices.
