Hypertension (High Blood Pressure) and Yoga: An Overview

by Baxter

On these hallowed blog pages, we have previously addressed several conditions that involve our cardiovascular system (heart and blood vessels), such as arrhythmias, strokes, hypotension and hypertension (also referred to as High Blood Pressure and Hypertension, or HTN). We even have at least six posts that at least mention HTN. However, due to the large percentage of adults who will develop HTN over the course of their lifetimes, I thought it worth revisiting. In 1999-2002, 28.6% of the U.S. population had hypertension. And this number seems to be on the rise. Plus, there is yet another study that demonstrates yoga’s beneficial effect on lowering blood pressure in those with mild to moderate hypertension! (For background information about what blood pressure is, see So, what is blood pressure, anyway?)

Why all the hype about HTN or high blood pressure, anyway?  Well, if you have HTN, you are at an increased risk of developing other more serious health problems, including heart attacks, strokes, rupture of your largest blood vessel (the aorta), chronic kidney disease, congestive heart failure, decreased blood supply to your legs, and problems with your vision. Some people develop HTN secondary to the presence of some other health condition that leads to high blood pressure, such as chronic kidney disease (hey, wasn’t that just mentioned?!), diseases of the adrenal and parathyroid glands (part of our endocrine system), pregnancy, and medications such as birth control pills, diet pills, some cold meds, just to mention a few. 

And some people are at a higher risk of developing HTN, if any of the following factors are present for you: obesity, chronic stress and anxiety, excessive alcohol consumption, excessive salt in diet, family history of HTN, diabetes, smokers, and African American ancestry. Part of the frustration for people who are diagnosed with HTN is that they often don’t have any really noticeable symptoms. I can’t tell you how many times I diagnosed a patient in my family practice with high blood pressure when they came in for a routine annual exam with no real complaints, or were in the office for some unrelated complaint, like a cold or headaches. This is why HTN is often referred to as the “silent killer,” as you may not know you have it until one of its complications like stroke or heart attack strike you.

Complexity in Nature by Brad Gibson

It’s been known now for at least 40 years that yoga practices can help lower blood pressure in people with HTN, starting back in the 60s and 70s with the work of Herbert Benson, MD, a cardiologist who used a particular kind of yogic meditation popular at the time (TM or transcendental meditation) to help lower the blood pressure in his patients who were not responding as expected to the newest medications of that era. Since then, other studies have shown similar results, including the newest study from the University of Pennsylvania, Philadelphia, still in progress, which is following 120 patients with mild to moderate elevations in their blood pressure. Already, with 58 people completing the study so far, there is small but significant decreases in blood pressure readings in the yoga group. This could be of greatest importance to patients who are labeled with “pre-hypertension,” where the blood pressure readings fall between 120/80 and 140/90.  This group of people is at much higher risk of going on to develop full HTN and is at higher risk than the general population of serious situations such as stroke and heart attack. However, if treated with yoga, they could drop their numbers low enough to avoid the need for medications to do the job.  In previous posts, Nina and Shari have talked about kinds of asana practices that have been shown to lower blood pressure, such as forward bends and certain inversions, as well as the effect on the baroreceptors that monitor and influence blood pressure moment by moment.  See Blood Pressure: Talking About Baroreceptors and Yoga and Just in Time for the Holidays: Inverted Poses.

As to how you might incorporate yoga practices into your efforts to lower your own rising blood pressure, you would likely want to add it to a broader approach to treatment, instead of substituting yoga for medications, for instance. Usually, a combination of aerobic activity, dietary changes, appropriate salt restriction, stopping tobacco use, lowering stress, and achieving an optimal body weight are the first line actions recommended when you are diagnosed with HTN. As we have shown before, yoga can help with many of those goals, such as weight management and stress, as well as improving will power, which could help with establishing all of those changes suggested from your usual dietary and lifestyle habits. But, independent of that, as this newest study again points out, yoga helps lower blood pressure on its own. It can do it via a balanced asana practice, via meditation practices and via breathing techniques. It is, of course, frustrating for those of us familiar with this data, that mainstream medicine has not embraced this cost-effective modality to any significant degree. If it were a pill, I suppose, it would be a no-brainer. 

And for those interested in developing a home practice for hypertension, due to the multiple factors that could influence your unique situation, I highly recommend you work one-on-one with an experienced yoga instructor to create the optimal practice for you. Yoga for high blood pressure? You bet!  

Will Yoga Cause a Stroke? Could it Prevent One?

by Timothy

There has been concern—and for some even fear—in the yoga community regarding the risk of strokes from doing yoga. How realistic is this?

Much of this fuss was set off by the New York Times writer William Broad, who warned that all the stretching of the neck in various yoga poses like Cobra and Shoulderstand could lead to tearing of the linguini-like vertebral arteries that run along either side of the neck bones, which could then lead to bleeding into the brain. But as I (and others) have written (see Man Bites Down Dog), Broad's analysis was alarming, lacked data to back his extraordinary contentions, and in all likelihood was way off. Still, it may be worth discussing the risk of strokes and what thoughtful yoga practitioners and teachers can do to prevent them.

Arteries of the Neck (from Gray's Anatomy)

Vertebral artery tears and resulting strokes often happen when someone makes an unaccustomed neck movement. The example that is often cited is when an elderly woman drops her head back into the hairdresser’s sink. In such a case, the movement in question is an extension of the neck (the cervical vertebrae), not so different from what happens in backbends like Cobra pose and Upward-Facing Dog. But it’s also at least theoretically possible to tear the artery when you go in the other direction and flatten the neck vertebrae, as in Shoulderstand and especially Plow pose. Even twisting poses could cause problems if you crank the head too far. Outside of yoga, such strokes also have been reported to happen when people simply turn their heads to the side or suffer minor trauma. It is estimated that 1.5 people out of every 100,000 suffer vertebral artery-related strokes every year.

I have observed many yoga students who hyperextend their necks in poses like Cobra and others who flatten their neck in poses like Shoulderstand and Plow. In the case of backbends, many students have the habit of over-arching from the neck. They compress the backs of their necks, and often arch too much from the back of the skull (the occiput), at the atlas-occipital joint. (The atlas is another name for the first cervical vertebra.) This habit is common in those with tight thoracic spines. When the thoracic spine is stubborn, people sometimes overcompensate by overarching the more flexible cervical and/or the lumbar spines. In other words, when one link in the chain is tight, people tend to move more than they should from the links above and below it.

When instructing backbends, I encourage students to try to keep the back of the neck long. Rather than looking up in a pose like Cobra, I encourage those with the habit of neck hyperextension to keep their gaze forward, which tends to keep them from tipping the head back too much. It’s also useful to think of originating the movement in your neck from the middle of the thoracic spine and the lower cervical vertebrae (where the neck attaches to the back).

Poses like Shoulderstand and Plow pose tend to flatten the neck. This is especially problematic if the student tries to move the chin towards the chest (an unfortunate instruction that some yoga teachers use). Instead, I encourage students in these poses to lift the front of the chest toward the chin, and actually slightly move the chin away from the chest. If you try this, you may notice that it lessens the feeling of pressure at the back of the neck.

In the traditional hatha yoga Shoulderstand, known as Viparita Karani (not to be confused with the restorative pose that uses the same name), the legs are in a jack-knife position. In other words, the pelvis is behind the spine and the feet are forward of the spine. This pose can be done safely without any props, especially if you follow the instructions of moving the chin slightly away from the chest. This is the version of Shoulderstand I’ll do if I wind up somewhere with no props.

Rare is the yoga practitioner who is flexible enough to do the modern, more-directly vertical version of the Shoulderstand—in which the legs are stacked directly over the hips and shoulders—without blankets or other props to raise the shoulders off the ground. To keep suppleness in your neck, the number of blankets required varies. For example, I use four folded blankets under my shoulders. Try to place your shoulders near the edge of the folded blankets so you graze the skin over C7, the lowest cervical vertebra, while you work to lift C7 away from the ground. Your breath should be soft, slow and even throughout the pose, and if at any point you can’t breath smoothly, or otherwise feel uncomfortable come down.

Plow pose is even more challenging to the neck, and I recommend the same blanket set-up. If you notice any discomfort at the back of the neck, however, I recommend either skipping the pose entirely or placing your feet higher, for example, on the seat of a chair.

In twists, try not to lead with your head. In other words, the turn should come from the vertebrae all along your spine, with no twist whatsoever from the atlas-occipital joint. One instruction I give if students feel any tension in the neck is to turn the head ever so slightly (say 1 millimeter) in the opposite direction of the twist. What this accomplishes is to stop people from trying to twist the skull on C1, a motion those joints are not meant to do. Even more conservative, is to not let the chin turn any more than the chest, in other words the nose and chest point in the same direction.

Beyond lessening the theoretical risk of a vertebral artery stroke, all the above advice will also tend to help avert yoga’s contributing to such musculoskeletal problems of the neck as arthritis and overstretching of spinal ligaments. Indeed, averting these problems is actually my primary reason for recommending doing the poses as I suggest. Broad generated tremendous publicity for his book by trumpeting the risk of vertebral artery strokes, and made the absurd, entirely unscientific calculation that yoga causes 300 strokes and 15 deaths per year in the U.S. My guess is that it’s more like in a one in a zillion scenario. 

Ironically, skillfully practicing the very poses that Broad recommends avoiding might actually lower the risk of the vertebral artery strokes. When you gradually stretch the arteries and surrounding tissues as could be expected with a regular yoga practice, the vessels would likely become more pliable, and resistant to tearing with sudden movement or trauma.

And the bigger picture is that vertebral artery strokes are a tiny percentage of all strokes, estimated to strike 269 people per 100,000 every year. Yoga’s documented ability to lower blood pressure, cholesterol and stress hormones, reduce inflammation, thin the blood, etc., in all likelihood greatly lowers the incidence of all types of strokes—as well as heart attacks and a host of other conditions. Just be sure to be mindful of contraindications. So, for example, if you have poorly controlled high blood pressure, you probably want to avoid inversions like Headstand entirely. The risk of having a stroke as a result is probably small, but it’s better to err on the side of caution.

Friday Q&A: Cautions for Inversions

Q: I’ve heard that some people should not do inversions, but you didn’t mention this in your post on Wednesday about inverted poses. Could address this?

A: Oops! My bad, as Buffy would say. It’s true that for certain medical conditions, inverted poses are, as they say, contraindicated. So I’m sorry I did not mention this earlier in my post "Just in Time for the Holidays: Inverted Poses".

First off, the poses you may need to be concerned about only include the full inversions and some of the partial inversions that are held for long periods of time.

If you have high blood pressure that is uncontrolled with medication, you should not do inverted poses, because, as I explained in my post (see here) they temporarily raise your blood pressure. And even if your high blood pressure is controlled with medication, talking with your doctor before doing full inverted poses is probably a good idea. People with heart problems should also consult their doctors.

If you are having eye problems, such as glaucoma or detached retina, inversions should also be avoided. Likewise, if you've recently had oral surgery. And those with neck problems should avoid the inversions that put pressure on their necks.

People with back problems will probably find that at least some of these poses may cause back pain, in which case, you should please come out of the pose and find an alternative (I’ve noticed Supported Bridge pose and Legs up the Wall pose can cause difficulties for people with lower back problems).

There are many yoga teachers who do not recommend inverted poses for women who are menstruating. However, as far as I know, there are no scientific studies to back up their concerns. What I recommend is that each of you do your own research on the subject, talking to your teachers, your gynecologist (I did that), and other female practitioners, and make up your own mind based on their advice.

Finally, if you are pregnant and not already experienced doing inverted poses, this is probably not the best time for you to start.

—Nina

CHRONIC STRESS: AN INTRODUCTION

by Nina

An ongoing theme that we’ll be exploring in depth on this blog is the negative effects of chronic stress on long-term health and the need for stress management as an important aspect of healthy aging. So perhaps it’s a good time for me to define exactly what we mean by “chronic stress” and to let you know a little about why it is such a serious problem.

I learned about dangers of chronic stress the hard way. Back in the early nineties, I had a job as the documentation manager and lead technical writer at a software start-up company, while at the same time I was raising two children. As you might imagine, the pressure was intense as our small company struggled to meet our first deadline, the first test of the product by real customers (who needed my manuals to teach them how to use the product!). As the deadline approached and I started working overtime, I began having difficulty sleeping. I also started losing weight because the stress made me so feel nauseated that I lost my appetite. Eventually I was so anxious, exhausted and nauseated that even though I met my deadline (and the company went on to success), I couldn’t bounce back to normal health. It took a year and half of therapy, medication, and lifestyle changes to recover completely.

Wounded Bird by Brad Gibson

Feeling stressed is not always a bad thing, however. It’s your body’s normal response to perceived danger or extreme physical activity (often called the “fight or flight response”), which is vital in keeping you safe and active. When you encounter a stressful situation, whether it is a grizzly bear or a stack of tax forms, your body releases hormones (adrenaline and noradrenaline) to provide you with the energy and alertness needed to cope with the situation. And anyone who has almost been run over an SUV knows the feeling: heart racing, rapid breathing, gut clenching. This is because in stress mode, your nervous system stimulates your organs and mobilizes energy by:

• raising your blood pressure
• increasing your heart rate and the blood supply to your skeletal muscles (and away from your gut)
• dilating your pupils and bronchioles, providing improved vision and oxygenation
• generating needed energy by breaking down sugar and fat stores for immediate use

Between stressful situations, your body needs to rest, recover, and acquire new energy, so your nervous system responds by:

• lowering your blood pressure
• reducing your heart rate, diverting blood back to the skin and gastrointestinal tract
• contracting your pupils and your bronchioles for reduced oxygenation
• stimulating your salivary gland secretion, accelerating digestion, and promoting normal movement of food through the gut

But what if the stress is long term? When you almost get hit by a car, escape from a bear or finish your taxes, the incident is over quickly and you bounce back to normal soon after. But if the stress is ongoing or “chronic,” maybe because of continuing job pressures (like mine at the software company), marriage problems, health problems, and so on, your nervous system is continuously on the alert and this can overtax your body potentially causing:

• heart disease
• hypertension (high blood pressure)
• insomnia and/or fatigue
• digestive disorders
• headaches
• chronic anxiety or depression
• weakened immune system

(Hmm, I just counted, and it seems I developed almost half of those symptoms, rather impressive in a weird sort of way.)

Of course, these symptoms are not only unpleasant but will seriously compromise your long-term health if you can’t manage to bring them under control. In addition, several age-related diseases, such as Alzheimer’s, Parkinson’s, and Diabetes are exacerbated by stress, and some theories of aging itself (such as the telomere theory I discussed last week) propose stress as a factor in the aging process itself.

I hope you’re not getting too stressed out by reading all of this! I credit yoga with helping me stay well since that breakdown. And in the coming weeks, we’ll be offering many different alternatives for managing your stress even as you take on the many challenges that life has to offer.