Alarmist scenario: Chronic fatigue syndrome.
More likely cause: Anemia, a thyroid disorder, depression, stress, or insomnia.
Reality check: The Centers for Disease Control and Prevention estimate that about 1 million people in the United States have chronic fatigue syndrome, making it fairly uncommon. Signs may include frequent headaches, flu-like symptoms, a sore throat, tender lymph nodes, extreme fatigue following mental or physical exertion, muscle and joint pain, and the inability to concentrate.
Rx: Get at least seven to eight hours of uninterrupted sleep a night, eat nutritious meals, exercise most days of the week, and try to reduce stress. Fatigue-causing ailments, like anemia and thyroid problems, can be diagnosed with blood tests and treated with medication and lifestyle changes.