What causes exhaustion?
That depends. If, like Krainson, you mean exhausted muscles, that’s caused by exertion. But it may accompany other serious medical problems. “With heart disease, with lung disease, with renal disease, with any chronic disease, you may be more easily fatigued — you may not be able to maintain the same activities as someone else,” Krainson says. Beyond tired muscles, exhaustion can be caused by nutritional deficiencies, illness, overwork, and too little sleep, Riley says. “Here in the United States, everybody overdoes it,” she says, and “most people don’t get enough sleep.” Riley’s list of common culprits also includes anemia, especially in women, and hypothyroidism (underactive thyroid).
