During cancer treatment, anxiety, depression, deep fatigue, digestive-system problems, breathing problems, hot flashes, night sweats and pain can all keep you from falling asleep and staying asleep. Studies have found that insomnia alters immune and endocrine function, and has a powerful influence on the risk of infectious disease. Since cancer treatments such as chemotherapy may also predispose a person to infections, this can be double trouble.
Sleep disturbances are associated with aberrant patterns of cortisol secretion, such as those found in insomnia, which are known to significantly depress the immune system, particularly the cells of the immune system responsible for mounting a defense against tumors. When we don’t sleep our bodies produce fewer natural killer (NK) cells and less melatonin, both of which can be implicated in increasing our risk of cancer. NK cells our in the front lines of our immune defenses. Sleep deprivation is also known to cause inflammation, which is one of the basic causes and characteristics of cancer.
Without sufficient sleep, our bodies makes fewer cytokines, a type of protein that targets infection and inflammation, effectively creating an immune response. Cytokines are both produced and released during sleep, causing a double whammy if you skimp on shut-eye.