Psychoneuroimmunology is the science of mind-body connection. It explores the interaction of our mind and emotions with all aspects of our physical being, including our immune system.
PNI has shown that our emotions, including stress, translate into chemicals in our bodies. These chemicals direct our bodies to function in ways that may not be optimal for long-term health. For example, they may direct our body to continually produce stress hormones that have a damaging effect over the long term.