What is hypertension?

Your heart beats all day, every day, pumping blood around your body. It circulates oxygenated blood around the arteries and veins, feeding the brain, muscles, tissues and cells with oxygen, and it pumps deoxygenated blood towards the lungs to replenish the oxygen supply. As the heart works, blood pushes against the artery walls. This creates pressure that, like all of the body’s homeostatic functions, is constantly fluctuating to meet changing demands.

Blood pressure is regulated by motion-sensitive nerve endings called baroreceptors. High blood pressure occurs when the baroreceptors aren’t working properly, or when blood flow is restricted – in exactly the same way that water pressure might cause your garden hose to fly off the tap because of a kink or blockage. When the blood vessels are dilated and functional, blood flows easily and blood pressure stays within normal levels. When the arteries become constricted by fatty deposits, or hardened with age, blood can’t flow so easily, and pressure increases. When this happens, the heart will begin working harder in order to ensure that blood still circulates around the body. The extra pressure this produces provides a temporary solution, but it puts a strain on the heart and blood vessels, which, long-term, results in damage.

Healthy circulation is vital. Without it, the organs, muscles and cells cannot access the oxygen they need to survive. If you have ever had a dead leg from sitting down for too long, you will be familiar with the sensation of pins and needles that occurs because of constricted blood flow. You can walk this feeling off, but when blood vessels are constantly restricted, the reduced blood flow will be detrimental to the heart and the brain. Lack of oxygen to any part of these organs can cause cells to die. This may result in a heart attack or stroke.

Can I prevent high blood pressure?

High blood pressure happens because the heart is pushed to beat harder or faster than it should. Chronic stress and an unhealthy lifestyle can result in hypertension.

Equally, you may have a family history of high blood pressure, and this leaves you at greater risk. If you do have a genetic predisposition, there’s no need to despair. This knowledge can actually help you to put steps in place that will prevent you from developing hypertension. Various choices that you make every day, which may promote or protect against high blood pressure, are well within your control. You can give up smoking, eat a well-balanced and healthy diet, take adequate exercise, manage your stress levels and practice slow, light breathing. The Buteyko Method can help you to develop a healthier body and moderate your blood pressure, without resorting to medication.

How is blood pressure measured?

Blood pressure is given as two measurements, for example 120/80 mmHg. The two numbers represent systolic and diastolic pressure. The top figure is the systolic pressure. This is the blood pressure when the heart is actively pumping blood. The lower number measures the pressure of blood between heartbeats when the heart is resting. MmHg is ‘millimeters of mercury’ which is the unit used to measure pressure.

Blood pressure is normally taken by a healthcare professional, though it is possible to take your own reading with a home-testing kit. An inflatable cuff is placed on the upper arm, and air is pumped into the cuff, increasing pressure around the arm. As the cuff tightens, the pressure temporarily restricts blood flow in the artery. A stethoscope is then placed on the artery and the cuff is released. When the first pulse of blood flows through the artery, the systolic reading is taken. The cuff is then released more, and the sound and pressure of the blood is carefully monitored. As the blood flow resumes, the artery is still partly constricted and the blood makes a turbulent sound as it flows through. As the blood begins to flow freely, this turbulence ceases. This is when the diastolic reading is taken.

One of the problems with high blood pressure is that you may not notice any symptoms or warning signs until things are really out of hand. You might only start to feel unwell when blood pressure reaches 180/110. But once your blood pressure is high, the problem can persist for the rest of your life. Some people never experience symptoms and only realize that there is a problem when they undergo a routine blood pressure check. If you do experience symptoms, these can include blurred vision, memory loss, a persistent headache, dizziness, low libido, nose bleeds, nausea, palpitations and breathlessness.

What is ‘normal’ blood pressure in adults?

• Normal healthy blood pressure is when systolic pressure (the first number) is less than 120, and diastolic pressure (the second number) is less than 80
• When the readings fall between 120 and 139 for systolic and 80 and 89 for diastolic, you are considered to have pre-hypertension
• Stage one high blood pressure is a systolic reading of between 140 and 159 and a diastolic reading of between 90 and 99
• Stage two high blood pressure is a systolic reading of 160 or more and a diastolic reading of 100 or more
• If your blood pressure is 140/90 or higher for a sustained period, you are considered to have hypertension

Can I check my own blood pressure?

Yes, it’s easy to take your own blood pressure readings if you purchase your own monitor. In fact, these days you can even do it with a cuff and a smartphone. Some people find that home testing actually returns more accurate results, because they feel more relaxed at home.

Here’s how to take your own blood pressure:

1. Sit quietly with your back supported and your feet on the floor. Roll your sleeve up, and rest your arm on an armrest, table or similar so that your elbow is at the same height as your heart.
2. Fix the cuff around your upper arm and use the instructions to measure your blood pressure. After you have taken a reading, leave the cuff in place, rest for a minute, then take another reading. If both readings are similar, work out the average. This will be your measurement. If the two readings are quite different, take a third and work out the average of the three.
3. It can be helpful to take a reading from each arm. This can produce more consistent results and flag up any potential issues. One study, published in The Lancet in 2006 reported that when readings are more than ten points different between one arm and the other, this may indicate a buildup of fatty deposits in the arteries⁴.

In order to ensure that you get the most accurate reading possible, it is important to avoid caffeine for at least two hours before measuring your blood pressure. You should also wait around half an hour after exercise, and, because blood pressure constantly fluctuates, try to measure at around the same time each day.

How can I lower my blood pressure naturally?

Dr. Buteyko made the connection between his worsening hypertension and his poor breathing patterns during a routine clinic in October 1952. He realized that over-breathing might be causing his blood pressure to increase. He described his findings in an interview on Russian television, saying: “I decided to check right away whether that was the case. How? By reducing and slowing down my breathing. I already had a headache, my heart and right kidney were in pain, so I began cutting down on my breathing. My headache disappeared, pain in my right kidney ceased, and heart ache discontinued within less than a minute after I reduced my breathing. To prove it was a true discovery, I inhaled deeply five times and pain pierced my head, heart and kidney. I tried my method again and everything returned to normal.”

It is generally acknowledged in scientific literature that regular practice of slow breathing can help to lower blood pressure. One 2006 study compared the impact of slow breathing and mental relaxation on blood pressure and found that slow breathing triggered the parasympathetic response and caused a drop in systolic and diastolic blood pressure, respiratory rate and heart rate5. In fact, slow breathing was better than relaxation, and resulted in a much bigger reduction of heart rate and blood pressure.

By practicing slow breathing regularly, it is possible to improve blood pressure long term⁶. This is at least partly due to the connection between hypertension and stress. Scientists have reported that people with high blood pressure experience significantly higher respiratory rates under stress than those with normal blood pressure, indicating a heightened stress response⁵. Breath retraining has been proven vital in the treatment and management of obstructive sleep apnea (OSA), a condition that is closely related to high blood pressure. A 2020 study states that around half of all OSA patients have high blood pressure, and 30 to 40 percent of hypertension patients have OSA, though this often goes undiagnosed⁷. Both OSA and chronic stress cause protracted activation of the sympathetic stress response⁸, unbalancing the autonomic nervous system.

The function of the baroreflex during sleep depends on the sleep-state. Its sensitivity increases during light non-REM sleep and its function is much better during deep non-REM sleep⁹. These phases of dreamless, restorative sleep are crucial for wellbeing. Conversely, baroreflex function has been found to be impaired in people with OSA and hypertension during non-REM sleep. It is believed that lower baroreflex sensitivity and an increased ventilatory response to CO² may cause a stronger stress response to apneas, increase daytime stress and potentially contribute to daytime hypertension.

OSA and high blood pressure are both common. It is possible for them to exist side by side without one necessarily causing the other. This means that treatments designed to alleviate OSA may have no impact on blood pressure. However, it is known that both conditions can be improved by practicing slow, light and deep breathing. The increased resistance created by full-time nasal breathing has also been demonstrated in several studies to lower blood pressure^{10, 11}.

Can I moderate my blood pressure during exercise?

During intensive exercise, we experience a fairly marked increase in blood pressure. In 1990, scientists investigated how nasal breathing impacted systolic blood pressure in healthy men during exercise. Participants used nasal dilators to increase their nasal airflow by almost 30 percent¹².

With the dilators in place, all of the participants were able to cycle at maximum load without mouth breathing. They also all experienced a much smaller increase in systolic blood pressure than normal. It was thought that the facilitated nasal breathing decreased the ventilatory load, meaning that the breathing muscles did not have to work so hard, and that this was responsible for the smaller spike in systolic blood pressure.

This study indicates that nasal breathing could help prevent the significant increases in blood pressure that come during intensive exercise.

Applying the Exercises: Denise’s Story

A lady called Denise came to me for help with her ill health. She had been suffering from constant fatigue, anxiety, high blood pressure, muscle pain, and brain fog. Her symptoms ranged from dizziness and a tight chest to feelings of constant air hunger.

Denise was in her fifties, but she was feeling so worn down by her poor health that she had little enthusiasm left for life. She had spent thousands of dollars visiting specialist doctors and healthcare providers. Eventually, her chiropractor suggested that she should investigate chronic hyperventilation as a possible cause of her problem.

I met Denise via Skype, and within minutes it was obvious that her breathing was very noticeable. Even at rest, her respiratory rate was fast and each breath was bigger than necessary. She breathed into her upper chest and I could hear a sharp intake of air every time she began to speak. She had no pre-existing respiratory conditions, but when she recalled the onset of her symptoms, twelve years earlier, she was able to identify that she had been under significant stress at that time.

It was obvious that the stress Denise had encountered had activated her fight or flight response, resulting in over breathing. Over the subsequent weeks, months and years, her body and brain had normalized this large volume of air, and it had become habitual for her to breathe this way. This produced the symptoms she was experiencing and caused her fatigue, high blood pressure and poor health.

In this first consultation with Denise, we discovered that she was unable to hold her breath after an exhalation for more than five seconds. Because this measurement was so low, I started by asking her to practice repeated, small breath holds. She was to hold her breath for five seconds after an exhalation, breathe normally for ten seconds and repeat for around five minutes before resting. This exercise is ideal for someone with a high sensitivity to CO2, because it avoids too strong an air hunger, which may cause discomfort and even panic. For the first week, I asked Denise to practice the following:

1. The many small breath holds exercise for five minutes each hour
2. The same exercise for ten minutes before bed
3. To try not to sigh
4. To stop taking big breaths before speaking
5. To switch to nasal breathing during the day and at night
6. To tape her mouth using MyoTape at night

A week later, when I spoke with Denise, she was able to hold her breath after an exhalation for ten seconds. She also already felt much better in control of her breathing, and was no longer experiencing feelings of air hunger at rest.

Next we tackled gentle reduced breathing and relaxation. Working from recorded exercises, which she used twice a day, Denise began to reduce her breathing volume towards normal and undo many years of stress. During the day, she also practiced light, gentle breathing for ten minutes every hour.

If your blood pressure is high it is important to approach reduced breathing gently. This allows your blood CO₂ to normalize without putting extra strain on your body. It encourages the accumulation of nitric oxide, which helps to dilate the blood vessels, and it activates the rest and digest part of your nervous system, encouraging relaxation. Your breath hold time will increase every week as you continue to practice. This will gently lower your blood pressure, and you will be able to depend less on medication. If you are on medication for your blood pressure, you should consult your doctor once your breath hold time reaches 15 to 20 seconds in order that your dosage can be adjusted as appropriate.

I met Denise online every week for a few months. During those months, her high blood pressure dropped to normal levels, her cholesterol reduced and her energy increased. She said she felt calmer than she had in a long time. Her overall health improved to the point that her doctor was able to alter her medication. Her breath hold time increased to a remarkable 28 seconds as her sensitivity to blood CO₂dropped.

When sensitivity to CO₂ is low, the function of the blood pressure receptors improves¹³. The body becomes better able to moderate blood pressure, maintaining it at healthy levels. This, along with the rebalancing of the autonomic nervous system that correct breathing and relaxation can achieve, explains the improvements in physical and mental health that changed Denise’s life for the better.

References:

1. WHO. “Hypertension.” World Health Organization, Published September 13, 2019. www.who.int/news-room/fact-sheets/detail/hypertension (accessed March 8, 2020).

2. Feldman, Adam. “What to know about high blood pressure.” Medical News Today, Published November 13, 2019. www.medicalnewstoday.com/articles/159283.php (accessed March 8, 2020).

3. U.S. Department of Health & Human Services. “High Blood Pressure.” National Heart, Lung and Blood Institute. www.nhlbi.nih.gov/health-topics/high-blood-pressure (accessed, March 8, 2020).

4. Clark, Christopher E., Rod S. Taylor, Angela C. Shore, Obioha C. Ukoumunne, and John L. Campbell. “Association of a difference in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta-analysis.” The Lancet 379, no. 9819 (2012): 905-914.

5. Kaushik, Rajeev M., Sukhdev K. Mahajan, Vemreddi Rajesh, and Reshma Kaushik. “Stress profile in essential hypertension.” Hypertension Research 27, no. 9 (2004): 619-624.

6. Mourya, Monika, Aarti Sood Mahajan, Narinder Pal Singh, and Ajay K. Jain. “Effect of slow-and fast-breathing exercises on autonomic functions in patients with essential hypertension.” The journal of alternative and complementary medicine 15, no. 7 (2009): 711-717.

7. Venkataraman, Shreyas, Soumya Vungarala, Naima Covassin, and Virend K. Somers. “Sleep Apnea, Hypertension and the Sympathetic Nervous System in the Adult Population.” Journal of Clinical Medicine 9, no. 2 (2020): 591.

8. Xie, Ailiang, James B. Skatrud, Dominic S. Puleo, and Barbara J. Morgan. “Exposure to hypoxia produces long-lasting sympathetic activation in humans.” Journal of Applied Physiology 91, no. 4 (2001): 1555-1562.

9. Silvani, Alessandro. “Physiological sleep‐dependent changes in arterial blood pressure: central autonomic commands and baroreflex control.” Clinical and Experimental Pharmacology and Physiology 35, no. 9 (2008): 987-994.

10. Ubolsakka‐Jones, Chulee, Phailin Tongdee, and David A. Jones. “The effects of slow loaded breathing training on exercise blood pressure in isolated systolic hypertension.” Physiotherapy Research International 24, no. 4 (2019): e1785.

11. Pessoa, Isabela, M. B. Sclauser, Verônica Franco Parreira, Guilherme AF Fregonezi, A. William Sheel, Frank Chung, and W. Darlene Reid. “Reference values for maximal inspiratory pressure: a systematic review.” Canadian respiratory journal 21, no. 1 (2014): 43-50.

12. Petruson, Bjorn, and Thorvald Bjurö. “The importance of nose-breathing for the systolic blood pressure rise during exercise.” Acta oto-laryngologica 109, no. 5-6 (1990): 461-466.

13. Trembach, Nikita, and Igor Zabolotskikh. “Breath-holding test in evaluation of peripheral chemoreflex sensitivity in healthy subjects.” Respiratory physiology & neurobiology 235 (2017): 79-82.