Psychoneuroimmunological research has shown that stress, social support and emotions may affect susceptibility to infectious disease by modulating the immune system. Salivary immunoglobulin A (S-IgA) has been studied as a stress marker. This antibody is found in secretions in the lining of the upper respiratory tract, the gastrointestinal system and urinary tract. S-IgA is important in the first line defence against pathogens e.g. bacteria, viruses & toxins.
An elegant study published in 1995 in the Journal of Advancement of Medicine, investigated the effect of induced emotional states of compassion or anger on levels of S-IgA. The investigators studied the immediate effects of a 5 minute induced mood state of compassion or anger on S-IgA levels over a 6 hour period. Thirty adults (mean age 38, age range 17 to 50, 13 males) were randomly assigned to three groups of ten individuals. All were in good health. They all refrained from smoking, exercising, eating or drinking except water, for at least 8 hours prior to the test period.
The subjects were asked to experience compassion/care or anger/frustration. They were instructed to experience these emotions at as deep a feeling level as possible. The subjects in the control group listened to music. After experiencing the emotional state for 5 minutes, saliva samples were collected immediately and then hourly for 6 hours.
41% of the compassion group and 18% of the anger group showed a statistically significant immediate increase in S-IgA, whereas only 12% of the control (music) group showed an increase, which was not significant. What was fascinating was that in the compassion group, S-IgA returned to baseline level after one hour and then there was a gradual increase in the levels of S-IGA over the following 6 hour period.
In contrast, in the anger group, there was a significant decrease in the S-IgA levels which only returned to baseline levels after 5 hours. These findings were statistically significant.
Mindfulness training cultivates a compassionate stance towards oneself and this also extends to others. There are clear health benefits of practising mindfulness, enhancing one’s immune system rather than suppressing it is one such example.
Rein, G., et al. (1995). “The Physiological and Psychological Effects of Compassion and Anger.” Journal of Advancement in Medicine 8(2): 87-105.