Breathe deep?

Dec 07 2010 Published by under Medicine

Winter has come to the Great Lakes, no matter what the calendar says.  This morning I walked out the door to take out the trash and the cold took my breath away.   I warmed up the car while I had breakfast, perhaps not the most environmentally friendly practice, but...

On my way to work, depending on my mood, I listen either to CBC Radio 2 or NPR.  This morning it was Morning Edition, a choice I regret.  This morning's health story was a credulous pile of poorly researched word salad about yogic breathing practices.

Yoga is very popular in these parts, and folks seem to love it.  According to my sources, it's both relaxing and a good workout.  According to NPR's story, though, it's much more.  We'll skip over the poor reporting aspect of this story, except to note that the reporter did not ask any pointed, skeptical questions, and didn't question any of the underlying assumptions and claims made by the people she interviewed.  And what were these claims and assumptions?

There are plenty of ways to relieve stress — exercise, a long soak in a hot bath, or even a massage. But believe it or not, something you're doing right now, probably without even thinking about it, is a proven stress reliever: breathing.

As it turns out, deep breathing is not only relaxing, it's been scientifically proven to affect the heart, the brain, digestion, the immune system — and maybe even the expression of genes.

This sounds pretty far-fetched, but let's see what they are actually talking about.

Mladen Golubic, a physician in the Cleveland Clinic's Center for Integrative Medicine, says that breathing can have a profound impact on our physiology and our health.

"You can influence asthma; you can influence chronic obstructive pulmonary disease; you can influence heart failure," Golubic says. "There are studies that show that people who practice breathing exercises and have those conditions — they benefit."

The reporter then talks to an instructor of pranayama---traditional yogic breathing---who describes some common techniques.

Research has shown that breathing exercises like these can have immediate effects by altering the pH of the blood, or changing blood pressure

OK, hold it right there.  Let's examine these first claims.  Breathing is part of the way we regulate our body's pH (acidity).  Our body only functions within a very narrow pH range centered on the slightly basic 7.40.  Various insults to the body, such as overwhelming infection, can disturb the pH, and the kidneys help regulate this in the long term, but brief corrections can be made by the lungs.  The lungs, in addition to absorbing oxygen, help dispense with carbon dioxide.   Carbon dioxide acts as an acid in the body, so rapid or deep breathing removes acid, raising the blood's pH.   The ability of the lungs to do this is quite limited, no least by the fact that blowing off acid consumes a lot of energy, and patients can tire, and then stop breathing completely.  Almost all alternative health claims that talk about pH and "acidity" are complete bunk.

That breathing techniques might lower blood pressure isn't far-fetched but it's unclear to me what clinical utility there is to briefly lowering blood pressure this way.  The piece goes on to make certain claims about being able to calm oneself with breathing techniques, which sounds like a good idea, but once again, I'm underwhelmed with what long-term clinical impact that might have.

But the real problem comes at the end of the piece.

In his new book, Relaxation Revolution, Benson claims his research shows that breathing can even change the expression of genes. He says that by using your breath, you can alter the basic activity of your cells with your mind.

"It does away with the whole mind-body separation," Benson says. "Here you can use the mind to change the body, and the genes we're changing were the very genes acting in an opposite fashion when people are under stress."

This "whole mind-body separation" problem is not unknown to the rest of us---most real doctors understand that the brain and the rest of the body are interdependent.  The real problem here, though, is this idea that yogic breathing somehow changes the basic fabric of our being, our genetic instructions.   There are some very important distinctions that were blurred here.  First, there is the difference between "genes" and "gene expression", a difference which Dr. Benson surely knows.  Genes are nucleic acids that encode instructions for making proteins.  Genes can be actively coding for these proteins, or can be "turned off" either permanently, or temporarily based on signals from feedback loops and other stimuli.  For example, if you drink a lot of milk, it's worth the energy expenditure for you to make lactase, the enzyme that helps digest milk sugars.  If you don't drink milk, it would be wasteful to make lactase, and the gene can be shut down.

So it's not beyond the pale to imagine that various stimuli can have an affect on gene expression (but no on the genes themselves).  The question becomes is there truly a measurable effect, and does that putative have any clinical significance (beyond lining the pockets of the author).  I was able to find one recent article that took a very small sample of patients who had leukemia, and made certain measurements of gene expression. While intriguing, the results are clinically irrelevant.

I said I wouldn't harp on the reporting, but I have learned to expect more from NPR.  This wasn't reporting, it was an infomercial.


Kumar, A., & Balkrishna, A. (2009). To study the effect of the sequence of seven pranayama by Swami Ramdev on gene expression in leukaemia patients and rapid interpretation of gene expression Journal of Clinical Pathology, 62 (11), 1052-1053 DOI: 10.1136/jcp.2008.061580

Raghuraj P, Nagarathna R, Nagendra HR, & Telles S (1997). Pranayama increases grip strength without lateralized effects. Indian journal of physiology and pharmacology, 41 (2), 129-33 PMID: 9142556

Pramanik, T., Sharma, H., Mishra, S., Mishra, A., Prajapati, R., & Singh, S. (2009). Immediate Effect of Slow Pace on Blood Pressure and Heart Rate The Journal of Alternative and Complementary Medicine, 15 (3), 293-295 DOI: 10.1089/acm.2008.0440

SINGH, V. (1990). Effect of yoga breathing exercises (pranayama) on airway reactivity in subjects with asthma The Lancet, 335 (8702), 1381-1383 DOI: 10.1016/0140-6736(90)91254-8

Cooper, S. (2003). Effect of two breathing exercises (Buteyko and pranayama) in asthma: a randomised controlled trial Thorax, 58 (8), 674-679 DOI: 10.1136/thorax.58.8.674
Bhargava R, Gogate MG, & Mascarenhas JF (1988). Autonomic responses to breath holding and its variations following pranayama. Indian journal of physiology and pharmacology, 32 (4), 257-64 PMID: 3215678

Pratap V, Berrettini WH, & Smith C (1978). Arterial blood gases in Pranayama practice. Perceptual and motor skills, 46 (1), 171-4 PMID: 25412

KOCHUPILLAI, V. (2005). Effect of Rhythmic Breathing (Sudarshan Kriya and Pranayam) on Immune Functions and Tobacco Addiction Annals of the New York Academy of Sciences, 1056 (1), 242-252 DOI: 10.1196/annals.1352.039

18 responses so far

  • Leeman says:

    Err.. If they're taking deep/quick breathing and removing CO2 from the bloodstream, shouldn't this raise the pH since Co2 is acidic?

  • ktraphagen says:

    I heard this report this morning too! I had the same reaction that you had, and I'm glad you have put some virtual ink down to draw attention to the deficits in this piece. You are right, NPR reporting is usually better than this!

  • You know that there might be something to this though, right? I mean, it might not have to set off our woo alarms...

    • PalMD says:

      you mean we can change our genes by breathing right? or that there may be some sort of genome or proteome level effect of breathing a certain way and there might be some clinical application? Or...?

      • I mean all of the above. Let me get to writing a bloggity post....

        • PalMD says:

          My big problem is the hype, the dude selling books that say "breathe like i say and fix yourself from the genes up!!!"

          • isis says:

            Fair enough and I will concede that there is a difference between accepting that there is basis for something to have a physiological effect and claiming that it is going to save the world.

            Then again, it just might save the world...

  • Diane says:

    Well, deep breathing has an effect on vagal cardiac autonomic function, heart rate variability. That's about it, I guess. Maybe that helps in moments of stress. Maybe it's a good habit to cultivate because of that, in case you really need it some day.

  • Speaking anecdotally, a few deep breaths goes a long way to defer tantrums in the Little Anthropologists as well as the parents. This is a significant tool of self-control at our house.

  • Samantha Vimes says:

    I have asthma. Sometimes people try to lead me through deep breathing exercises. It never fails to trigger a brief attack for me.

    I have extremely well developed muscles for breathing, and have dislocated a rib during asthma attacks, because the harder it is to breathe, the harder I work at it naturally. If I can't perform over 100% of what's expected for my demographic on a flowmeter, I'm doing very badly-- when you spent your developmental years playing saxophone, singing, and doing distance running and other endurance exercise, you develop great breathing control.

    None of that means jack when my pharynyx and bronchial tubes have contracted, my aveoli (am I remembering that correctly) are semi blocked by inflammation or congestion, etc. It is uncomfortable and sends my body scrambling into emergency measures (higher blood pressure, faster heart beat, etc) to cope.

    I get very angry when people tell me they can fix my asthma by training me how to breathe. If my sports and music instructors hadn't trained me in deep breathing, I would have been diagnosed sooner, given more medicine with less argument, and I wouldn't dislocate my rib. But more than that, I've lived with this long enough to know what *doesn't* work.

  • BB says:

    Woo aside, I find that yoga makes me stronger, helps my balance, and calms me. My neck doesn't hurt since I started it (used to bother me, like a constant "crick").
    I still take Accolate for asthma.

  • daedalus2u says:

    I have not read Benson's book, but the “mind-body” connection that he is talking about is mostly mediated through nitric oxide. The “relaxation response” comes from the neurogenic production of NO. It is physiologically equivalent to the placebo effect; the neurogenic production of NO that switches physiology from a “fight or flight” state to a “rest and relaxation” state.

    It can be difficult for those not versed in NO physiology (or yoga) to tell the difference between the high NO state of the relaxation response and the low NO state of the fight or flight response. It is extremely important that you trigger the appropriate physiological state or you can cause serious long term damage. When the “fight or flight” state is triggered via yoga it is called the Kundalini kindling.

    Both of these states can be triggered neurogenically. When athletes prepare for an athletic event, they attempt to trigger the “fight or flight” state because this gives them greater resources for doing their athletic activities. Those greater resources come at the expense of turning off systems not involved in athletic activities, systems such as healing. Stay in the “fight or flight” state too long, and you end up with chronic health problems, the health problems of chronic stress, heart disease, PAD, hypertension, chronic fatigue, and so on. These chronic health problems occur because the “fight or flight” state has not been turned off, so the resource allocation to healing pathways has not been restored. The only way to turn those healing pathways back on is via increased NO, either neurogenic (as in the placebo response or the relaxation response) or via my NO producing bacteria.

    When the “fight or flight” state is triggered via yoga it is called the Kundalini kindling or Kundalini syndrome (my hypothesis). Many yoga references tell noobies to be very careful to not try these techniques without proper supervision. If the “fight or flight” state is triggered too hard, and too long, there will be permanent damage. If you need to run from a bear, your body will let you run yourself to death. That is a “feature” because being caught and dropping dead from exhaustion are evolutionarily equivalent. Escaping from the bear a few steps short of dropping dead from exhaustion is infinitely better than being caught. Triggering the Kundalini state neurogenically is an extremely valuable fighting technique. Turning off other ATP consuming pathways gives a burst of energy that is extremely valuable in short-term strength and endurance limited events such as hand-to-hand combat.

    In the “fight or flight” state you feel as if you have more energy and feel more capable than you actually are. These are delusions induced by the “fight or flight” state. Very useful delusions when you need to run from a bear and to be caught is certain death. When you are running a race? Not so much unless winning is more important than a long and healthy life. Your body will let you injure yourself this way.

    In terms of breathing, these effects are not produced through hyperventilation, but through “breath control”, the limiting of how many and how deep breaths are taken and for how long. There are two major effects both brought on by hypoxia, but which ones dominate depend on the minutia details of physiology, your basal NO/NOx status (mostly nitrite levels) and which tissue compartments become hypoxic, how hypoxic and for how long.

    Hypoxia has two effects, the first is that when mitochondria become hypoxic, the respiration chain becomes reduced and what O2 is available can pick up electrons from the respiration chain and make superoxide. This superoxide is produced inside the inner matrix of mitochondria and can't get out (it is charged and there are 2 lipid membranes between it and the cytosol). What happens is that NO diffuses in (NO is uncharged and freely diffusible through lipid membranes). This pulls down the NO level, NO desorbs from cytochrome c oxidase, more O2 can bind, cytochrome c oxidase reduces that O2 to H2O and the respiration chain becomes more oxidizing and less superoxide is produced. This has the effect of lowering the O2 partial pressure at the mitochondria which increases the O2 concentration gradient so more O2 can diffuse to the mitochondria at a higher flux. This is what accelerated aerobic respiration. This is what happens in the fight or flight state to maximize aerobic ATP production. This is a low NO state.

    The other effect that hypoxia can have is the reduction of nitrite to NO. Every tissue compartment has nitrite reductase activity and this nitrite reductase activity is inhibited by O2. This is extremely complicated and is not well understood by anyone. I suspect that generation of NO via hypoxia is a part of how breath techniques of yoga can raise NO levels (there may be neurogenic NO production too, but that is aerobic and would be made more difficult by partial hypoxia).

    The fight or flight state is much easier to get into. Everyone can do that, and doesn't need training to do so, just a bear chasing you. The high NO state is much more difficult to achieve.

  • JJM says:

    I heard the report and responded quite like you did. Before the breathing story, they had a report on Rolfing (painful massage) that was just as credulous.

  • tideliar says:

    I was thnking of writing this up too, but PalMD wins the day (saves the day?). and that rolfing report was utter shite too. NPR fail.

  • k says:

    Deep breathing is all well and good, as when one says to someone who's upset, "Take a few deep breaths and calm down a little." That woo-peddling NPR story is truly feculent.

  • antipodean says:

    Mind-Body? Has a serious scientist actually been a dualist since WWII?