A new study has uncovered a possible link between a higher risk of breast cancer and working night shifts. Researchers examined women of the same age both with and without breast cancer; a third of the women with cancer had worked nights for a long period of time. Women who worked long night hours for 30 years or more were twice as likely to develop breast cancer. Previous studies have shown that nurses and other health-care professionals who work night shifts have a higher risk of cancer, but this study links the cancer rate to any occupation that involves long night hours.
New study links workers to breast cancer.