Yoga has a somewhat mixed reputation. I recently saw a flier from a group warning against “satanic traps” that listed yoga as one of the traps. (They listed vegetarianism and meditation, too, which just goes to show.) Some people view yoga as a physical exercise. Others see it as a spiritual exercise, or something mystical (pro-mystical believers like this; others see it as more new-age nonsense). Regardless of which view you take, science has found that yoga bestows some significant health benefits on the practitioner.
Science Daily reported a couple of years ago that yoga reduces inflammation in the body.[i] If you know something about inflammation, you know that it causes a host of health issues. Inflammation is the body’s response to infection or injury, and it serves a useful purpose when there is an infection to fight or a wound to heal. However, inflammation is the body’s knee-jerk response to anything it doesn’t like, such as stress, and chronic inflammation can cause serious, and sometimes deadly diseases such as periodontitis, atherosclerosis, hay fever, rheumatoid arthritis, and even cancer (such as gallbladder carcinoma).[ii] Chronic low-level inflammation can also prevent weight loss—even when you are doing everything else right.
In the study reported by Science Daily, Ohio State University researchers found that women who regularly practiced yoga had lower levels of the cytokine interleukin-6 (IL-6) in their blood than women of the same age and weight who did not practice yoga. IL-6 is key to the body’s inflammation response, so practicing yoga on a habitual basis should help protect against chronic inflammation.
The researchers also saw that when experiencing stress, the yoga practitioners’ inflammatory response was lower than non-practitioners, which means they were able to handle life’s stressors better, experiencing less bodily damage as a result.
The study at Ohio State University is just one of a wealth of clinical studies that reveal yoga’s many benefits. Studies have shown that yoga raises heart rate variability (HRV), a critical vital sign used as an indicator of a person’s state of health. HRV is the variation in the time interval between one heartbeat and the next. Your heart rate changes from beat to beat. When you inhale your heart rate speeds up, and when you exhale it slows down. So rather than referring to a fixed pulse of, say, 60, the heart rate will actually vary between, say, 55 and 65. HRV is a measure of this naturally occurring irregularity in the heart rate. About 30 years of clinical research has shown that when HRV levels are high, a person experiences lower levels of stress and greater resiliency. When HRV levels are low, this is an indication of greater stress and lower resiliency.
So anything that raises HRV is good for your health, and yoga is an effective means of doing that. A study of healthy people who practices Iyengar yoga showed that during yoga practice, the subjects’ HRV was significantly higher compared to placebo and control groups.[iii] Because yoga strengthened the vagal tone necessary for high HRV and had no negative side effects, the researchers recommended that yoga be considered as an intervention in cardiac rehabilitation programs.
Another study looked at the effect of what the researchers called “rhythmic formulas such as the rosary and yoga mantras” on HRV and “baroreflex sensitivity”—scientists’ cute little way of saying “maintaining a healthy blood pressure.” As you may have guessed, yoga mantras and rosary recitals had pretty much the same effect: HRV went up, blood pressure maintenance improved.[iv] Of course, not all yoga practitioners chant mantras, but maybe they should start. Either that, or take up saying the rosary.
There have been a number of studies of the effect of yoga on people suffering from type 2 diabetes. All have shown beneficial changes in glucose tolerance and insulin sensitivity, lipid profiles, blood pressure, oxidative stress, etc.[v] If that’s what yoga can do for people who are truly ill, think what it can do for a reasonably healthy person.
Yoga has even come to work with us as studies show that worksite-based yoga programs improve HRV and relieve stress on the job. Work-related stress is on the rise, accompanied by an increase in cardiovascular and metabolic diseases created by a sedentary work environment. A recent study looked at the effects of yoga and mindfulness sessions in the workplace. Participants in either session experienced higher HRV and lowered stress in comparison with the control group.[vi] The degree of improvement in HRV and stress was equivalent for both the yoga and the mindfulness groups; one wonders what might have happened if they had combined them?
This is just a tiny fraction of all the studies that show that yoga strengthens the body, relieves stress, raises HRV, combats inflammation, and is just generally very, very good for your health. If yoga is a satanic trap, it’s going to be hard to figure out just what old Beelzebub is up to this time.
[i] “Yoga Reduces Cytokine Levels Known To Promote Inflammation, Study Shows,” Science Daily, January 14, 2010.
[iii] “Iyengar Yoga Increases Cardiac Parasympathetic Nervous Modulation Among Healthy Yoga Practitioners,” K. Khattab, A.A. Khattab, J. Ortak, G Richardt, H.Bonnemeier; eCAM2007;4(4)511–517.
[iv] “Effect of Rosary Prayer and Yoga Mantras on Autonomic Cardiovascular Rhythms: Comparative Study,” L. Bernardi, P. Seight, G. Bandinelli, S. Cencetti, L. Fattorino, J. Wdowczyc-Szulc, A. Lagi; BMJ, v.323, December 2001.
[v] “The Influence of Yoga-Based Programs on Risk Profiles in Adults with Type 2 Diabetes Mellitus: A Systematic Review,” K.E. Innes and H. K. Vincent; eCAM2007;4(4)469–486.
[vi] Effective and Viable Mind-Body Stress Reduction in the Workplace: A Randomized Controlled Trial,” R.Q Wolever, K.J. Bobinet, K. McCabe, E.R. Mackenzie, E. Fekete, C.A. Kusnick, M. Baime; Journal of Occupational Health Psychology, Vol 17(2), Apr 2012, 246-258.
