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Psychological stress can have a number of different effects on the body and its function, including effects on the immune response. Stress can worsen the symptoms of most medical conditions. Nevertheless, at this time there is little proof that stress alone is actually a cause of medical problems or cancer. Cancer is a complex disease that results from a combination of hereditary (inherited) and environmental factors.
Although some epidemiologic studies have suggested an association between lifestyle stress and cancer, most studies fail to confirm this association. Stress is known to affect the functioning of the immune system, and it is known that compromised immune function may play a role in the development of cancers. However, there has been no scientific proof that stress can increase cancer risk.
Medically reviewed by John A. Daller, MD; American Board of Surgery with subspecialty certification in surgical critical care
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