I have experienced extreme fatigue on a fairly short-lived but regular basis for my entire life, and have often coped through impromptu napping, after which I would typically feel fine. Many years ago, low blood sugar was thought to be the culprit. Today, for the first time ever, I woke to find my skin jaundiced. I was too tired to get up and look at the whites of my eyes in the mirror, and the jaundice has disappeared. Any ideas?