Usually, medicines taken by mouth are partially digested by enzymes in the body. But grapefruit juice interferes with this process. As a result, researchers warn that mixing the juice with certain medicines may lead to trouble. It can result in too large a concentration of the medicine. Among the medications affected are some taken for heart problems, allergies, depression, and AIDS. Check with your doctor to see if grapefruit juice is a safe combination with drugs you may be taking.
Mayo Clinic Proceedings, Vol. 75, No. 9

Women undergoing breast cancer therapies such as radiation or chemotherapy often feel tired, nauseous, and anxious. According to researchers, many of them drop exercise from their routine in response. Now, a study shows that a regular walking program can lessen some of the side effects of these treatments. Women who walked regularly improved their ability to function physically. They also reported less pain, better general health, and improved social functioning.
Journal of Clinical Oncology, Vol.19, No. 3