The Benefits of Slow Breathing

There are all manner of purported hiccup “cures,” which include everything from chewing on a lemon, inhaling pepper, or, our dog’s favorite, eating a spoonful of peanut butter. In my video How to Strengthen the Mind-Body Connection, I talk about the technique I’m excited to try the next time I get hiccups: “supra-supramaximal inspiration,” where you take a very deep breath, hold for ten seconds, then, without exhaling, breathe in even more and hold for another five seconds, and then take one final, tiny breath in and hold for five last seconds to achieve “an immediate and permanent termination to hiccups…”

When I was a kid, I taught myself to control my own hiccups using slow-paced breathing, and, as an adult, was so excited to see there was finally a case report written up on it.

There’s a nerve—the vagus nerve—that goes directly from our brain, to our chest, and to our stomach, connecting our brain back and forth to our heart and our gut, and even to our immune system. The vagus nerve is like the “‘hard-wired’ connection” that allows our brain to turn down inflammation within our body. When you hear about the mind-body connection, that’s what the vagus nerve is and does. “There has been increasing interest in treating a wide range of disorders with implanted pacemaker-like devices for stimulating the vagal afferent [vagus nerve] pathways,” but certain Eastern traditions like Yoga, QiGong, and Zen figured a way to do it without having electrodes implanted into your body.  

“A healthy heart is not a metronome,” as a study titled exactly that explains. “Your heart rate goes up and down with your breathing. When you breathe in, your heart rate tends to go up. When you breathe out, your heart rate tends to go down.” Test this out on yourself right now by feeling your pulse change as you breathe in and out.

Isn’t that remarkable?

That heart-rate variability is a measure of vagal tone—the activity of your vagus nerve. Next time you’re bored, try to make your heart rate speed up and slow down as much as possible within each breath. This can be done because there’s an entirely other oscillating cycle going on at the same time, as you can see at 2:08 in my video, which is the speeding up and then slowing down of your heart rate, based on moment-to-moment changes in your blood pressure. And, as any physics student can tell you, “all oscillating feedback systems with a constant delay have the characteristic of resonance,” meaning you can boost the amplitude if you get the cycles in sync. It’s like pushing your kid on a swing: If you get the timing just right, you can boost them higher and higher. Similarly, if you breathe in and out at just the right frequency, you can force the cycles in sync and boost your heart rate variability, as you can see at 2:36 in my video.

And what’s the benefit again? According to the neurophysiologic model postulation it allows us to affect the function of our autonomic nervous system via vagal afferents to brainstem nuclei like the locus coeruleus, activating hypothalamic vigilance areas.

Huh?

In other words, it’s not just about curing hiccups. Practicing slow breathing a few minutes a day may have lasting beneficial effects on a number of medical and emotional disorders, including asthma, irritable bowel syndrome, fibromyalgia, and depression. In the United States, we’ve also put it to use to improve batting performance in baseball.

To date, most studies have lacked proper controls and have used fancy biofeedback machines to determine each person’s resonant frequency, but, for most people, it comes out to be about five and a half breaths per minute, which is a full breath in and out about every 11 seconds. You can see the graph at 3:34 in my video. When musicians were randomized into slow-breathing groups with or without biofeedback, slow breathing helped regardless. It’s the same with high blood pressure. As you can see at 3:52 in my video, you can use this technique to significantly drop your blood pressure within minutes. The hope is if you practice this a few minutes every day, you can have long-lasting effects the rest of the day breathing normally.

Practice what exactly? Slow breathing—taking five or six breaths per minute, split equally between breathing in and breathing out. So, that’s five seconds in, then five seconds out, all the while breathing “shallowly and naturally.” You don’t want to hyperventilate, so just take natural, shallow breaths, but be sure to simply breathe really slowly. Try it the next time you get hiccups. Works for me every time!


For more tips, watch my video on How to Stop Hiccups.

And, because slowing down our pulse in general may also have beneficial effects, I encourage you to check out:

Every time I’m amazed by ancient wisdom, I have to remind myself of the video I did on toxic heavy metals—Get the Lead Out. So, though traditional healing methods may offer a plethora of insights, they still need to be put to the test.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

The Health Benefits of Laughter, Tears, and Kisses

In my video, Music as Medicine, I explored a study about how listening to Mozart can reduce allergic reactions. This reminded me of a similar study on humor, which I discuss in Laughter as Medicine. In the study, researchers took a group of people with dust mite allergies and directed half of them to watch a Charlie Chaplin video and the other half to watch the Weather Channel. The researchers then injected all subjects with dust mite poop. In the subjects who watched the humorous video, their allergic response was significantly reduced and this reduction lasted for a matter of hours. This suggests that “the induction of laughter may play some role in alleviating allergic diseases.”

Is there a chance that it might suppress our immune system too much? Apparently not. In fact, if you have people watch a comedian for an hour, their natural killer cell activity goes up, compared to watching nothing. Their white blood cell count, the number of immune cells in their bloodstream, also goes up. The level of immune-boosting interferon and antibody production go up as well and even stay up the next day. So, your body is actually pumping out more antibodies because you saw a funny video the day before. In short, humor seems to offer the best of both worlds at preventing over-reactive allergic responses, while also boosting immune protection.

There is a catch, though. You actually have to laugh. And the more you laugh, the better your natural killer cell activity gets. Exposure to a humorous video without laughing did not significantly affect immune function. Those who didn’t physically laugh did not benefit. This reinforces that it is not the funny video that improved immune function, but our laughter in response. Natural killer cells play a significant role in viral illness and various types of cancer. So, being able to significantly increase the activity of these cells using a brief and non-invasive method could be clinically important the next time you have a cold or cancer.

Laughter, like music or healthy food, offers potential benefits without any risks. Or…almost no risks. You’ve heard of side-splitting laughter? In a rare case, a 67-year-old woman attended laughter therapy sessions where, evidently, rapture led to rupture. Thankfully, you can’t actually laugh your head off, but you can laugh until you wet yourself. “Giggle incontinence,” as it’s called in the medical literature, is actually quite common in women, and is no laughing matter.

Does this mean that the next time you go to the theater, you should choose the comedy over the tear-jerker? Not necessarily. Researchers took people with a latex allergy and had them watch a weather video versus a heart-warming drama. Because viewing the weather information video did not cause emotion with tears, it failed to modulate allergic responses. The tear-jerker, however, successfully reduced the allergic response, but only in those whose tears were actually jerked. So, when it comes to improving allergies, laughing and crying both work, if you actually do them.

Anything else you can do? Kiss! There’s actually a whole science of kissing, which sounds like a pleasant enough college major, until you realize it’s about all the diseases you can get. But if you take people with seasonal pollen or dust mite allergies and have them kiss someone in a room for 30 minutes, they have a significant reduction in their allergic reactions, for both the pollen and the dust mites. If you instead just have them hug for that 30 minutes, there’s no benefit. Bottom line: Kissing significantly reduced allergic responses in patients with both allergic rhinitis (runny nose and itchy eyes) or allergic dermatitis (like a rash). “Collectively these findings indicate that the direct action of love may be beneficial,” though evidently cuddling wasn’t quite direct enough.

With all the side effects of antihistamine drugs, you’d think it would have been easy to get people to sign up for the kissing study. But, it was conducted in Japan where, apparently, they “do not kiss habitually.” The follow-up study, which found a similar benefit for an even more direct action of love, was also performed by researchers who apparently did not speak English as their primary language, evidenced by their speculation about females having more “organisms.”


Did I say “Mozart study”? Yes, there have been a bunch of them, in fact. I had fun with them in my videos Music as Medicine and Music for Anxiety: Mozart vs. Metal. I don’t go seeking out these peripheral topics; I just stumble upon them in the journals. There’s so much wonderful, juicy medical science out there. I wish there were dozens of different NutritionFacts.org-type resources where one could find evidence-based reviews of the latest in the science of wellness. There could be another ten or so websites just on nutrition alone! If anyone out there is interested, I’d be more than happy to share all my know-how to facilitate its creation. I did help the Lifestyle Medicine Foundation develop LifestyleFacts.org. Check it out if you haven’t already.

For less funny and racy ways to combat allergic diseases, see my videos:

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

The Health Effects of Heavy Metal Music

As I discussed in my video Music as Medicine, the stress-reducing effects of music appear to extend throughout the clinical spectrum—even to the critically ill, intubated in an intensive care unit. Those listening to Mozart through headphones cut stress hormones like adrenaline in half compared to those with headphones playing nothing, which resulted in a lower mean arterial blood pressure. But are all types of music just as relaxing? That’s the subject of my Music for Anxiety: Mozart vs. Metal video.

Researchers compared the effects of Mozart, Pearl Jam, and Enya on normal, healthy subjects. After listening to Mozart for 15 minutes, people reported a significant reduction in tension. With new age music, they also felt a reduction in tension, as well as greater relaxation and less hostility, but they reported significant reductions in mental clarity and vigor. After listening to grunge rock, people said they felt more hostile, tired, sad, and tense, with reductions in caring, relaxation, clarity, and vigor. But these were subjective measures—asking people how they felt. What about objective measures?

After 30 minutes of classical music, the stress hormone cortisol significantly dropped in the research subjects. But if instead of listening to Beethoven’s Symphony no. 6, Opera 68, they listened to techno—Cyber Trip, Techno Shock, or Techno Magnetiko—their stress hormone levels went up. Endorphin levels also went up, which may make you think, “Oh that’s nice,” until you realize that endorphins are our body’s natural painkillers—they go up after a variety of aversive stimuli, like getting burned or prodded.

These results may just be a function of the music’s tempo. The research shows that people get the same bump in breathing and blood pressure from listening to fast classical music like Vivaldi’s Presto, which was found to be as stimulating, or even more so, than the Red Hot Chili Peppers.

What about heavy metal music? Researchers randomly assigned participants to self-selected music, classical, heavy metal, or silence. “Listening to self-selected and classical music produced increased feelings of relaxation as well as sitting in silence, but not for the heavy metal condition.” Compared to relaxing and pleasant Renaissance music, exposure to arousing and “unpleasant” heavy metal causes a heightened amylase response in men. Amylase is an enzyme in our saliva that digests starch. When we go into fight or flight mode, we start immediately churning out the enzyme to provide sugars for quick energy. So, you get a spike in amylase when you go skydiving, if you’re dunked into cold water, or… if you make a guy listen to heavy metal for ten minutes. With all that extra enzyme, if he’s eating bread while banging his head, he can end up digesting it better!

Metal is more likely to cause the medical community indigestion, though. Although the American Medical Association’s Group on Science and Technology admits there’s “no evidence that this music has any deleterious effect on the behavior of adolescents,” that doesn’t stop them from suggesting there’s anecdotal evidence that those who identify with such bands as “Slayer” and “Metallica” may be at risk for drug abuse or even “participation in satanic activities.” In response, one doctor wrote to the medical journal to reply: “for every teenager who commits suicide or some crime under the influence of heavy metal music, there are dozens of white-collar criminals engaged in such activities as insider trading, savings and loan fraud, [and] government corruption….”

Maybe we should instead be blaming Bach or Barry Manilow.


What about smells instead of sounds? See Orange Aromatherapy for Anxiety, Lavender for Generalized Anxiety Disorder, and Wake Up and Smell the Saffron.

Don’t forget about dietary interventions for pain and emotions. Check out:

You can also learn about another dimension of mental health in my video Plant-Based Diets for Improved Mood and Productivity.

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations: