Yoga (ba) GABA
Evidence that yoga can enhance anxiety-killing neurotransmitters in the brain
Posted March 15, 2013
One of my standard recommendations for people who have anxiety or depression is to practice yoga. There are controlled clinical trials demonstrating its efficacy (1)(2)(3), and who hasn't felt that amazing sense of serenity and well-being after a particularly good yoga class? Part of treating anxiety is to bring people down from the state of constant alertness, to help someone be comfortable in his or her own skin for once. Yoga, through the process of holding (sometimes) uncomfortable positions and breathing through the stress, is a direct physical practice teaching you to get through a psychological stress. Eastern ways of viewing stress as a wave to allow to crash over you and pass by rather than as something you can fight off or entirely prevent can be helpful tools for learning to cope.
All well and good. Binge drinking can help you relax (short term) and teaches you how to deal with discomfort in a very physical way too. But I don't recommend it for anxiety. Binge drinking and heavy alcohol use will often make anxiety much worse.
Why does yoga help and a flood of alcohol hurt? Well, the money is on GABA. Gamma-aminobutryic acid is a neurotransmitter I've made brief mention of before. GABA is the chief inhibitory neurotransmitter in the mammalian nervous system. It cools things off and chills things out. People with depression and anxiety have been shown to have low amounts of GABA in their cerebrospinal fluid. MRI spectroscopy has been used to estimate the amount of GABA in people who are depressed, and the levels are low compared to controls (4).
Activate the GABA receptors in the brain with ambien, xanax, or a glass of wine, and you get relaxed and sleepy. When these substances are constantly in the brain and then rapidly withdrawn, you suddenly have overexcited GABA receptors and you can get unfortunate side effects such as insomnia, anxiety, and seizures.
Medicines often used for anxiety or seizures (or both) increase GABA itself. These treatments include depakote, lithium, SSRIs, tricyclic antidepressants, and a treatment for very resistant psychosis and depression, electroconvulsive therapy (shock treatments). And researchers at Boston University Medical School have found increases in the brain (measured via MRI) with yoga.
This trial was a pilot study of 8 experienced yoga practitioners and 11 comparison subjects. None had any history of psychiatric illness or seizures. The yoga people were asked to do 60 minutes of yoga postures and breathing. The control group was asked to read quietly for an hour. Then everyone got an MRI spectroscopic examination. Fun! The people who did yoga ended up with 27% increase in GABA in their noggins compared to controls. Since GABA is relaxing and anti-anxiety, that's good! Turns out, though, that the yoga practitioners had lower baseline GABA, but since the study was so small, it just so happened that all the women in the yoga group were in the luteal phase of the menstrual cycle (the second "premenstrual" half, after ovulation), and the women in the controls happened to be in the follicular stage. Turns out that our GABA levels are lower in the "premenstrual" half of the cycle (so give me that glass of wine, honey...).
In 2010 the same group at BU did a second, somewhat larger study (5) comparing walkers and yoga practitioners. Again, healthy people were studied, not anyone with psychiatric illness. This time, 19 yoga practitioners and 15 walkers did yoga or walked for an hour three times a week for twelve weeks. The yoga practitioners reported improved mood and anxiety compared to the walking controls, and MRIs showed increased GABA in the thalamus (a part of the brain) of the yoga practitioners compared to the walkers. The increase in GABA correlated with the decrease in anxiety scores, which makes sense. Since there is a body of evidence that exercise is helpful in depression and anxiety (6), it is interesting to see that yoga could be even more helpful than regular exercise.
Yoga as a specific practice isn’t “evolutionary”. The modern practice of yoga is at the most about 80 years old, despite some resources on the internet that claim it is 6000 years old. I don't see our distant ancestors practicing downward facing dog. But yoga combines physical activity with forced acute attention on the present. Lose your focus in tree stand, and you lose your balance. In my mind, yoga and other mindful meditation practices emulate, to some respect, the focus and attention we had to have while hunting and gathering. We couldn't be thinking about the mortgage or Uncle Phil getting drunk at last year's Christmas party. We had to be focused on the trail, signs of water, the color and shapes of leaves or berries that would identify edible species, and the evidence of prey living near or passing by. Evolutionary medicine is about using processes and foods to which our bodies are adapted to make low-risk and powerful interventions that can help us be healthier and happier. It’s not about rejecting the modern or recreating the past.
There are many ways to add mindfulness and a present focus to our everyday lives, and growing evidence that it is good for our brains to do so. One interesting resource is calm.com, and of course several of the Psychology Today blogs focus on mindfulness, including Turning Straw Into Gold by Toni Bernhard, J.D.
Copyright Emily Deans, MD