Hardly a day goes by without a story on television, in the newspaper, or on the Internet about new medical research findings. You might hear about a new drug to treat Alzheimer’s, a promising “cure” for cancer, or a breakthrough discovery in Parkinson’s disease. Or you might see articles about particular foods or dietary supplements that are said to promote health or prevent or slow the course of illness. Should you try to get these drugs for a family member who is sick? Should the person change his diet? Take more vitamins?