How Breathing Influences Blood Pressure—And Why It Matters More Than You Think

Understanding how your breathing affects your blood pressure could save your life. Many of us know that high blood pressure is associated with an increased risk of stroke and heart disease. But did you know it is also linked to (among other things) kidney disease, vision problems, cognitive decline, and sexual dysfunction?

In fact, erectile dysfunction is sometimes referred to as the “canary in the coal mine”. This is because it can be caused by poor circulation, which may signal more serious underlying cardiovascular issues.

Most of us have had our blood pressure taken when we go to the doctor. Blood pressure measures the force of blood pressing on the walls of your arteries, ideally around 120/80 mmHg. The first number is the pressure when the heart contracts, and the second is when the heart relaxes. The pressure is influenced predominantly by how hard the heart pumps and the resistance created by blood vessels. How fast the heart beats can also have an impact. By developing functional breathing patterns, we can maximise our body’s natural ability to keep our blood pressure in a healthy range.

Baroreceptors play an important role in regulating blood pressure. These receptors act like pressure sensors in your arteries. They help regulate blood pressure by sending signals to the brain to adjust how fast and hard (stroke volume) the heart beats, and to dilate or constrict blood vessels. This is critical when we are active, and particularly important when we move from lying to standing. Poor breathing patterns, like shallow upper chest breathing, can make these sensors less responsive, causing higher blood pressure. Slow, deep breaths can restore sensitivity, reducing blood pressure. Those breaths also stimulate the vagus nerve, engaging a relaxation response, reducing your heart rate.

Breathing through the nose can also help reduce your blood pressure. Nasal breathing produces nitric oxide (NO). This only happens when breathing through the nose, not the mouth. Some NO is produced in the blood vessels, but it is a small amount compared to the volume created in the nasal cavity. NO is important for reducing blood pressure as it is the body’s primary vasodilator. Put simply, NO helps our blood vessels to relax and widen (vasodilation).

Aterioles (blood vessels smaller than arteries but bigger than capillaries) provide an excellent example of the dramatic effect NO can have. The diameter of some arterioles can double in size when fully dilated. That’s a fourfold increase in volume. This can only happen when we are producing and utilising the NO produced in the nasal cavity. When a blood vessel widens, there is less resistance to blood flow, and blood pressure is reduced.

Carbon dioxide (CO2) also impacts blood pressure. If you hyperventilate (breathing more than you need to), you can end up exhaling too much CO2. As I wrote in a previous blog, the Bohr effect, which ensures the transfer of oxygen into our cells, requires CO2. When less oxygen is transferred to your cells, your body compensates by increasing your heart rate and blood pressure.

Like NO, CO2 is also a vasodilator, so if you don’t have enough in your blood vessels, not only is less blood transferred into your cells, but the vessels constrict, especially in the brain. This can lead to feelings of dizziness, light-headedness, and even fainting. To counteract the oxygen reduction, the heart can pump faster and more forcefully, while blood vessels constrict. The outcome? Increased blood pressure.

Therefore, functional breathing that maintains healthy levels of CO2 in the body also promotes healthy blood pressure.

One of the most interesting theories about how breathing influences our blood pressure is through the thoracic pump. This is the idea that as the diaphragm moves down, the change in pressure in the chest cavity draws blood into the thoracic veins (the veins in our chest). It is also thought that increased abdominal pressure during inhalations may also help with circulation in the legs and feet. When we exhale, the blood from the veins is propelled into the heart. This is understood to return blood to the heart more efficiently, helping to lower blood pressure.

There are other influences that breathing can have. It can:

• engage the parasympathetic nervous system, keeping us calm

• reduce the production of stress hormones like cortisol and adrenaline

• improve our heart rate variability (the time between heartbeats: high is good, low is bad).

If you’re managing high blood pressure, you should seek professional medical advice on possible causes and treatments. Reviewing your breathing patterns may be one of the most powerful and overlooked tools you have.

Disclaimer

This blog is for informational purposes only. It is not medical advice. Always consult a healthcare professional for personalized guidance and treatment.