Elevated psychological stress over time can increase risk for disease. Some studies point to increased inflammation and oxidative damage to cells as the pathway. Mindfulness meditation has been shown to reduce circulating levels of proinflammatory biomarkers in the blood.

It remains unknown whether meditation also increases naturally occurring antioxidants such as glutathione that protect our cells from oxidative stress. 

Rodrigues de Oliveira et al. [Brain, Behavior, & Immunity] conducted a randomized controlled trial to test the effects of a mindfulness-based intervention on well-being as well as proinflammatory and antioxidant biomarkers in public school teachers.

The researchers randomly assigned 76 meditation-naïve Brazilian public school teachers (average age = 45; 71% White, 100% female) to an 8-week mindfulness-based health program for educators or an 8-week applied neuroscience course for educators. Respective groups convened once weekly, and 10-30 minutes of homework was assigned daily for everyone.

Mindfulness training included mindful breathing, compassionate communication, loving-kindness and self-compassion, mindful listening, walking meditation, and the body scan. The neuroscience psychoeducation curriculum covered topics such as neuron biology, nervous system development, neuroplasticity, and the biology of memory and emotion.

Participants were assessed at baseline and immediate post-intervention on self-report measures of stress, quality of life, mood, resilience, and plasma biomarkers of inflammation (IL-1 β, IL-6, IL-8, IL-10, IL-12, TNF) and antioxidant glutathione metabolic activity (cystine, homocysteine and glutathione).

The results showed the mindfulness group significantly increased quality of life and resilience and decreased perceived stress and negative affect compared to controls at immediate post-intervention.

The mindfulness group also showed significant decreases in pro-inflammatory markers (IL-6 and IL-8) and increases in antioxidant activity (glutathione and cystine) compared to controls at immediate post-intervention. 

There were no group differences in IL-12 or homocysteine after the intervention. Levels of IL-1 β, IL-10, and TNF were undetectable in these physically healthy teachers. This was in part because these cytokines are usually only elevated due to certain illnesses, and in part because the assay technique used was unable to detect very low levels of IL-1 β and TNF. 

The study shows a mindfulness-based intervention can improve well-being and reduce perceived stress in public school teachers better than a control group. Mindfulness training also impacted physical health in terms of reducing biomarkers of inflammation and oxidative stress.

While prior studies showed increased glutathione levels in Zen, Tai Chi, and yoga practitioners, this is the first study to show increases due to a mindfulness-based intervention. The study is limited by the absence of longer-term follow-up data, initially planned on, that could not be obtained during COVID-19 pandemic social restrictions.

Reference:

Rodrigues de Oliveira, D., Wilson, D., Palace-Berl, F.,... Demarzo, M. (2021). Mindfulness meditation training effects on quality of life, immune function and glutathione metabolism in service healthy female teachers: A randomized pilot clinical trial. Brain, Behavior, & Immunity, 18, 100372.

Link to study