Stress can have damaging effects on physical, mental and emotional health, especially if it becomes chronic. Stressful emotions can suppress immune, digestive, sleep and reproductive systems, which may cause them to stop working normally. When people focus on the things that bring them joy, gratitude and deep fulfillment – the emotional state is changed – which then changes our chemistry by lowering cortisol levels and heightening endorphins. This mind-body connection is especially important during cancer treatments.