Our understanding of the ways in which meditation works in the body and brain is becoming more and more nuanced with every study that comes out. Not only does a meditation practice seem to change the structure of the brain in certain ways, but it also seems to affect the way it functions. One way researchers can track this is by measuring the levels of neurotransmitters, hormones and biomarkers. A new study finds that eight weeks of meditation can significantly alter the stress response in people with generalized anxiety disorder, and this is evident in the levels of stress hormones and inflammatory markers.
The study will be published in the journal Psychiatry Research.
The researchers recruited for the study 89 people with generalized anxiety disorder (GAD). According to the NIMH, over 10 million people will be affected by GAD within a given year; nearly 20 million will have it at some point in their lifetimes.
The team randomly assigned the participants to an eight-week MBSR program or to a Stress Management Education course. Mindfulness-Based Stress Reduction (MBSR) was developed at the University of Massachusetts Medical School by Jon Kabat-Zinn. It's generally an eight-week program, with weekly meetings, and instructions for home practice. (Mindfulness teaches one to be more in the present moment, and to pay attention to one's thoughts with curiosity, and nonjudgmentally.) A lot of previous research on meditation has compared a group doing the practice to a control or wait-list group, rather than to a group undergoing another active treatment. So, since there’s probably some placebo effect at play in that kind of study, the researchers wanted to reduce this possibility in the current study and get closer to a randomized clinical trial.
To test the participants' stress responses before and after the intervention, the team had the them do an old lab standard, the Trier Social Stress Test, where a person has to give a little lecture in front of a panel of researchers and then do some mental math. The participants' blood is drawn to take measurements of stress hormones, in this case cortisol and adrenocorticotropic hormone (ACTH), and inflammatory proteins (IL-6 and TNF-α).
At the end of the eight-week period in which participants took their respective courses, those in the MBSR group had significantly reduced levels of ACTH, IL-6 and TNF-α (cortisol reduction didn't differ significantly between the groups). Those in the education course, however, had increased in these measures slightly, perhaps from having to be subjected to a second episode of the stress test, where they knew what was coming.
“Mindfulness meditation training is a relatively inexpensive and low-stigma treatment approach, and these findings strengthen the case that it can improve resilience to stress,” said lead author Elizabeth A. Hoge, who’s studied the connection between MBSR and anxiety reduction in the past.
Plenty of previous research has found that meditation can reduce both physiological stress—measured by brain activity, structure and stress hormones—and people’s perceived reaction to stress. For example, a study from Harvard in 2009 found that after an eight-week course of MBSR people had significant reduction in volume in the amygdala, the part of the brain that governs stress. And these reductions were correlated to the subjective feeling that one’s stress levels were lower. A meta-analysis from Johns Hopkins in 2013 found that meditation was linked to significantly reduced anxiety (and depression and insomnia). Other studies have linked meditation to reduced levels of stress hormones and inflammatory proteins, so it’s very likely that this new study is accurate, even though it’s fairly small.
Given how unpleasant life with an anxiety disorder can be, it's probably not a bad idea to try MBSR, or another form of meditation. (It's generally best to do it under the instruction of a meditation teacher or mental health professional.) The research so far shows that it has some significant benefits, on several levels, and might be used as an alternative or addition to other types of treatment. But more research will be needed to suss out all the circumstances in which it's most effective.
