One of the most common (and obvious) causes of fatigue is not getting enough sleep -- or not getting enough good (restorative) sleep. Stress and/or depression
can cause this kind of sleep disturbance -- as well as difficulty getting the sleep and/or a awakening too early.
Another, less obvious, cause of poor sleep is sleep apnea
. This is where the person stops breathing (usually without fully waking up) for brief periods throughout the night. Snoring is sometimes, but not always, associated with this disorder. Frequent daytime fatigue is a common sign of sleep apnea. If you have noticed that your boyfriend's breathing is interrupted while he sleeps -- he should definitely get this possibility checked out. Most communities have sleep clinics that specialize in diagnosing sleep disorders.
Bottom-line -- constantly recurring daytime fatigue is not normal -- and not something that your boyfriend (or you) should have to put up with. Your boyfriend should definitely talk with the doctor about this.
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