Feeling like you're constantly tired and sluggish? A lack of energy is a key symptom of lethargy and you're certainly not alone in the feeling. Around three out of five Americans say they feel more ...

Lethargy is when you feel exhausted and have little energy. A nap won't help. It can be caused by things like stress or certain medicines, but it also can be a symptom of a serious health condition.

Sleep is one of those things you just can't live without. A lack of sleep can interfere with your body's ability to recover and build muscle, lead to weight gain, and impair brain function and ...