It’s sometimes difficult to determine the exact reasons for fatigue. Many times, it occurs as a result of adrenal malfunction, or other dysregulation. Sometimes, however, it can even be caused by medical conditions such as diabetes.
Glycemic index is a measure of how quickly the body absorbs the sugar in carbohydrate. If you choose foods which are high on the G.I. index scale, you run the risk of both fatigue and adrenal exhaustion.