<human>:  I'm writing a research paper about the effects of stress on the immune system; can you provide me with some quality information about this subject?
<bot>: Research studies have shown that stress can lead to a weakened immune system and increased susceptibility to illness. Stress hormones, such as cortisol, have been shown to suppress the body's response to infection, leading to an increased risk of infection. Long-term psychological stress can cause systemic changes to the immune system, reducing its ability to fight off bacteria and viruses. Stress can also increase inflammation in the body, resulting in a pro-inflammatory environment, which can further affect the immune system and increase the risk of long-term diseases such as cardiovascular disease and cancer. Additionally, stress can cause changes to the body's normal circadian rhythms, which can also affect the immune system.