What Happens to Your Blood Pressure When You Sit In a Sauna

Sitting in the sauna for relaxation is quite common. However, sauna use and blood pressure are linked in many beneficial ways. Regular sauna sessions can offer many health benefits, including improved heart health.

Short-Term Effects on Blood Pressure

Sauna bathing provides effects such as reduced blood pressure and improved vascular function immediately after exposure. Acute exposure to heat in a 20-30 minute session causes vasodilation (widening of blood vessels), which improves blood flow, similar to a moderate exercise session.

In another study, blood pressure decreased significantly compared to baseline after a 25-minute sauna session, though a rise in blood pressure and heart rate was seen during the actual session.

More clinical research is needed to clearly establish how sauna heat affects blood pressure and other cardiac outcomes.

Long-Term Effects on Blood Pressure

Regular and frequent sauna bathing can reduces the risk of hypertension (high blood pressure) and other cardiovascular diseases. Studies show that:

• The combination of sauna and physical activity significantly lowers blood pressure.
• Regular exposure to heat may help blood vessels become more flexible and responsive, supporting long-term heart health. 
• Heat therapy lowers diastolic and mean arterial blood pressure (blood pressure within the arteries). It can reduce blood pressure by up to 4 mmHg.
• The effects of heat therapy on blood pressure can reduce mortality in people with hypertension and cardiovascular problems.
• Increased frequency of sauna bathing was associated with lower death rates from cardiovascular problems and stroke.

Heat therapy, such as a sauna, can provide greater benefits when combined with exercise than a sedentary lifestyle. 

How Does Sauna Reduces Blood Pressure?

Reduces Vascular Resistance

Sauna improves blood pressure by causing vasodilation. Acute sauna bathing (30 min) has been shown to reduce arterial stiffness and improve blood flow via nitric oxide release. Nitric oxide is a chemical that dilates blood vessels and improves blood flow.

The systolic blood pressure (the top number) may stay the same or decrease slightly, while diastolic blood pressure (the bottom number) often decreases more noticeably due to reduced vascular resistance.

Increased Heart Rate

An immediate effect of sauna heat is an increase in heart rate, as the heart pumps more blood to the skin. Acute exposure to heat increases core body temperature, which can cause hypothermia. It increases blood flow to the skin, promoting sweating as a cooling mechanism.

A sudden increase in blood flow can raise heart rate as the heart pumps more blood to meet the body’s increased oxygen demand. 

Heart rate during sauna use can reach levels similar to moderate physical exercise. For most healthy individuals, this combination of lower blood pressure and higher heart rate is well tolerated.

Reduces Stress Hormones

Stress plays a significant role in many conditions, including hypertension. Although data are limited, a recent review found that sauna bath may help reduce stress hormones (i.e., cortisol, β-endorphins, and adrenocorticotropic hormone).

Considering the role that stress plays in causing hypertension, sauna can be a beneficial therapy, especially for high blood pressure.

Benefits of Sauna

Sauna is a traditional steam bath that uses passive heat therapy. It is used for relaxation purposes and is becoming increasingly common in many countries.

While sitting in a sauna, the body is exposed to high temperatures, which initiate a series of physiological responses. The latest research indicates that sauna bathing offers several health benefits, including:

• Hypertension
• Stroke
• Improved cardiovascular function
• Musculoskeletal pain
• Chronic headache

Side Effects of Sauna

A reduction in blood pressure in a sauna can sometimes cause problems for certain people:

• An increased exposure to heat may cause dehydration. A further decrease in blood pressure can cause dizziness, light-headedness, or blurred vision. Drink plenty of water to prevent side effects.
• People with certain medical conditions, such as psoriasis, should consult a healthcare provider before using a sauna.
• If you are taking any blood pressure-lowering medications, it is important to monitor your blood pressure closely. An additional drop in blood pressure may cause orthostatic hypotension (a sudden drop in blood pressure when standing).
• Excessive sweating can also reduce blood volume, which can further lower blood pressure. Drink plenty of water before and after the sauna.