Here are some key points about yoga and blood pressure. More detail and supporting information is in the main article.
- "Yoga" means "union" in Sanskrit
- Some research shows that regular yoga might positively affect blood pressure
- It is not yet clear exactly how yoga influences human physiology
What is yoga?
Can yoga lower blood pressure? Some research suggests that it can.
Yoga is a physical, spiritual, and mental discipline that began in India. Since its inception, around the 5th or 6th century BC, yoga has developed into a broad variety of yoga schools. The best known are the Hatha and Rāja yoga schools.
In brief, yoga involves:
- Gentle physical activity
- Controlled, focused breathing
Yoga instructors use a variety of terms for various "poses" - often using words from the classical Indian language, Sanskrit. Yoga itself means "union" in Sanskrit.
Yoga's popularity has risen in the West since the 20th century and is now studied for its potential benefits on human health.
Effect on blood pressure
Different schools of yoga vary in their approaches. One branch of yoga is known as Iyengar. This form was recently used in a trial testing its benefits for blood pressure.
To examine its effects, researchers asked participants with untreated prehypertension or stage 1 hypertension to perform Iyengar exercises over a 12 week period. Blood pressure results were compared with a group of individuals who received "enhanced usual care" - an intervention based on individual dietary adjustments. The authors concluded:
"Twelve weeks of Iyengar yoga produces clinically meaningful improvements in 24 hour systolic blood pressure and diastolic blood pressure. "
However, the trial involved only 57 participants and, therefore, its results need to be replicated.
Yoga has been put to the scientific test by numerous researchers. One, in particular, has devoted much of her career to investigating the health benefits.
Debbie Cohen of the Perelman School of Medicine at the University of Pennsylvania, recently published results of the Lifestyle Modification and Blood Pressure Study (LIMBS).
This is one of the few randomized controlled trials investigating yoga and its impact on blood pressure. It compared 12 weeks of yoga with other standard measures designed to lower blood pressure.
Published in 2016 in The Journal of Clinical Hypertension, the form of yoga used was Hatha, which means "willful or forceful."
The trial compared results across people who were randomized into one of three programs:
- 43 people did 12 weeks of yoga - 90-minute classes twice a week, with the gradual introduction of home yoga, guided by DVD.
- 48 followed a program of health education and walking - including nutritional classes and motivational guidance, and a gradual increase of the exercise to 180 minutes of weekly walking, or 10,000 daily steps.
- 46 people did both the yoga and the healthy living - although people in this group could opt to leave out the home yoga added to the biweekly classes.
All three programs were found to reduce resting blood pressure. For all participants, readings were lower at 12 weeks and 24 weeks than at the start of the study.
The difference in blood pressure reduction was larger for the yoga groups at 12 weeks than for the group following only the healthy lifestyle. But this improvement did not persist at 24 weeks.
Although the improvements in blood pressure were small, the authors believe they could be important as even a small reduction in blood pressure has health benefits.
For example, the paper mentions high-quality research showing that even a systolic blood pressure reading (the 'top' number) dropping by 2 mm Hg cuts the risk of dying from heart disease by 7 percent, and the risk of stroke death by 10 percent.
The American Heart Association (AHA) recommends more research to be done into the blood pressure benefit of lifestyle measures such as yoga, to see if it could delay the need for drug treatment.
The AHA published a review of the current evidence before Cohen's most recent results. The statement, published in the journal Hypertension in 2013, analyzed a number of trials that gave positive results for yoga programs in lowering blood pressures by modest amounts.
However, the trials were limited in size and design, so the AHA concluded that it was not yet possible to recommend yoga as a treatment for high blood pressure. They also say that yoga would certainly do no harm to heart health.
How does it work?
Physical activity is known to lower blood pressure, so this could be one factor that explains why yoga may provide benefit.
Yoga is not a high-energy form of exercise, though. It is equivalent to walking on a treadmill at 3.2 kilometers per hour (about 2 miles per hour). According to researchers who tested the heart and metabolic rates of people doing yoga:
"Yoga practice incorporating sun salutation postures exceeding the minimum bout of 10 minutes may contribute some portion of sufficiently intense physical activity to improve cardiorespiratory fitness in unfit or sedentary individuals."
The meditation element of yoga may also have an effect on the body. It might be that a reduction in stress and stimulation of the body might impart physiological benefits, says the AHA.
Transcendental meditation is a similar relaxation technique - but without the yoga poses - that may also have these balancing effects on the autonomic nervous system, including reducing high blood pressure during times of mental stress.
These effects may "balance" the part of the nervous system that controls automatic functions, such as the heart's pumping action. One researcher explains that "yoga, meditation, and music decrease sympathetic nervous system activity," adding that receptors in arteries and the heart and lungs are "sensitized."
But there is no clear proof to explain how relaxation lowers blood pressures exactly.
Other lifestyle effects on blood pressure
There are a number of lifestyle changes that can help lower blood pressure.
One of the studies designed to measure yoga's impact on blood pressure included comparisons with exercise and dietary salt intake:
- One group did brisk walking for 50-60 minutes, 4 days per week
- Another reduced their salt intake from food to at least half the amount they were eating before
- The third group did 30-45 minutes of yoga a day on at least 5 days of the week
This was an 8-week study of 113 people, with results published in the Indian Journal of Community Medicine. All three groups enjoyed reduced blood pressure compared with a control group of people who had none of the three interventions. The authors concluded that all three lifestyle measures could be recommended for people with high blood pressure.
This is one of the numerous studies carried out in Asia demonstrating scientific support for yoga's effects on blood pressure. However, due to the relatively small numbers of people tested, these studies need to be replicated and standardized before solid conclusions can be drawn.
Exercise and salt-lowering are recommended by the AHA as ways to reduce blood pressure. They also recommend reducing stress. Other healthy lifestyle measures include:
- Stopping or not taking up smoking
- Keeping a healthy weight or reducing overweight and obesity
- Limiting alcohol intake
Yoga is good for general health
Whether yoga lowers blood pressure or not, it certainly is a safe lifestyle choice when performed sensibly with proper guidance.
As well as the limited evidence for blood pressure, scientific testing has also linked yoga and other meditation practices to improved wellbeing in general, finding that it reduces:
One of the problems for medical researchers trying to prove the benefits of yoga is that the improvements they observe could be due to other elements of a healthy life. For instance, people who regularly practice yoga are more likely to eat more healthily and take part in other forms of exercise.
It is difficult to adjust the results of trials to take account of these factors. No doubt, as more large-scale research is conducted, the effects of yoga on health will become clearer.